AN99047 Application UBA2050(A)/51(A;C) One-Chip Telephone Ap
|
|
|
Top Searches for this datasheet
Application UBA2050(A)/51(A;C) One-Chip Telephone
AN99047
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
Abstract
UBA2050, UBA2050A, UBA2051, UBA2051A UBA2051C telephony application line powered electronic telephone sets. They offer line interface functions, speech functions, dialling ringer functions. They perform interface between telephone line transducers such microphone capsule, earpiece buzzers. transmission part range TEA106x- TEA111x-family. contain also dialler circuit DTMF pulse dialling. integrated supply with internal voltage regulator supplies dialler available supply point external use.
Accepted version
Philips Electronics N.V. 1999 rights reserved. Reproduction whole part prohibited without prior written consent copyright owner. information presented this document does form part quotation contract, believed accurate reliable changed without notice. liability will accepted publisher consequence use. Publication thereof does convey imply license under patent- other industrial intellectual property rights.
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
Application UBA2050(A)/51(A;C) One-Chip Telephone
AN99047
Author(s): Erik Coenders, Fred Dongen, Gino Knubben Philips Semiconductors Systems Laboratory Eindhoven, Netherlands
Keywords Basic telephone Transmission/Dialler/Ringer Low-end Chip Telephone UBA2050(A)/51(A;C) regulator
Number pages:
Date: 23/12/99
Application UBA2050(A)/51(A;C) One-Chip Telephone
Summary
Application Note AN99047
This report provides application support designing electronic telephone sets with One-chip telephone UBA2050(A) UBA2051(A;C) with speech, dialling ringer functions. supply point with internal voltage stabilizer integrated these ICs. detailed description several circuit blocks these well possible settings adjust transmission characteristics dialler/ringer arrangements given. aspects protection discussed also. Furthermore application example UBA2050(A)/51(A;C) given some measurement results this application presented. demonstration boards, prepared UBA2050(A) prepared UBA2051(A), also used basic telephone. advantage printed circuit board several types telephones meet requirements several countries. APPENDIX gives list abbreviations definitions used this report, APPENDIX diagrams application example APPENDIX dialling procedures UBA2050(A)/51(A;C).
Application UBA2050(A)/51(A;C) One-Chip Telephone
CONTENTS
Application Note AN99047
INTRODUCTION BLOCK DIAGRAM DESCRIPTION TRANSMISSION PART 3.1.1 characteristics supply blocks 3.1.2 Supply 3.1.3 Supply 3.1.4 impedance 3.1.5 Microphone amplifier 3.1.6 Receive amplifier block 3.1.7 Automatic gain control 3.1.8 DTMF amplifier 3.1.9 Internal MUTE. 3.1.10 Anti-sidetone networks DIALLER PART. 3.2.1 Timing/Control. One-pin oscillator Start-up after off-hook Start-up incoming ringer signal Line disconnect 3.2.2 Pulse dialler Pulse dialler Flash generator Timing selection 3.2.3 Tone generator 3.2.4 output 3.2.5 Keyboard Keyboard structure. Functional keys Keyboard scanning principle Keytone generator 3.2.6 Resistor options Resistor options settings Scanning principle 3.2.7 Dialling procedures RINGER PART 3.3.1 Ringer input frequency measurement. 3.3.2 Melody Volume
Application UBA2050(A)/51(A;C) One-Chip Telephone
APPLICATION EXAMPLE Description application Polarity guard protection High performance line interrupter Low-cost line interrupter Speech transmission Oscillator Dialler/ringer Ringer circuit stage arrangements Gain boost selection Keytone buzzer Settings performance application 4.2.1 behaviour settings. Supply possibilities. 4.2.2 Transmission impedance Send receive Side tone 4.2.3 Dialling DTMF dialling Pulse dialling Flash 4.2.4 Start-up Disconnect Off-hook start-up Line disconnect Ringer start-up
Application Note AN99047
ELECTROMAGNETIC COMPATIBILITY HINTS PRINTED CIRCUIT BOARD LAYOUT APPLICATION COOKBOOK. REFERENCES LIST ABBREVIATIONS DEFINITIONS APPLICATION WITH UBA2051. DIALLING PROCEDURE UBA2050(A)/51(A;C)
APPENDIX APPENDIX APPENDIX
Application UBA2050(A)/51(A;C) One-Chip Telephone
Fig.1 Fig.2 Fig.3 Fig.4 Fig.5 Fig.6 Fig.7 Fig.8 Fig.9 Fig.10 Fig.11 Fig.12 Fig.13 Fig.14 Fig.15 Fig.16 Fig.17 Fig.18 Fig.19 Fig.20 Fig.21 Fig.22 Fig.23 Fig.24 Fig.25 Fig.26 Fig.27 Fig.28 Fig.29 Fig.30 Fig.31 Fig.32 Fig.33 Fig.34 Fig.35 Fig.36 Fig.37 Fig.38 Fig.39 Fig.40 Fig.41 Fig.42 Fig.43 Fig.44 Fig.45 Fig.46 Fig.47 Fig.48 Fig.49 Block diagram UBA2050(A)/51(A;C) UBA2050(A)/51(A;C) pinning Principle basic application Fig.51 Fig.52 Supply configuration VLN, Vref versus line current. voltage behaviour Current consumption transmission part versus Adjustment Vref means Rreg2 Rreg1 Supply configuration versus line current versus input current trickle mode well ringer mode Equivalent impedance Microphone channel Frequency response microphone amplifier different temperatures Distortion line signal Microphone noise versus line current. Common mode rejection ratio microphone Receive channel Receive gain versus frequency: influence temperature Distortion earpiece signal load Noise level across earpiece gain setting open input microphone gain versus line current different RAGC values DTMF channel UBA2050(A)/51(A;C) DTMF gain versus frequency: influence temperature Distortion DTMF line signal versus input signal DTMF Wheatstone bridge (left) TEA111x family anti-sidetone bridge (right) Equivalent average line impedance Dialler start-up after off-hook Dialler start-up incoming ringer signal; VDD, CE/FDI oscillator signal Dialler start-up incoming ringer signal; signal Dialler line disconnect Block diagram DTMF generator Keyboard structure C1-C4, R1-R4 Input/Output stage configuration Voltage drop across interrupters, including Rprot resistor Low-cost line interrupter Resonator equivalent circuit connected oscillator. Series parallel transformation Correction Parallel series transformation DTMF attenuation network arrangements Keytone arrangements Line voltage across function line current application example `real' `complex' termination Behaviour during pulse dialling digit Behaviour during flash Start-up after off-hook; IC-voltages line voltage VA/B Ringer start-up; capacitor discharged before start-up
Application Note AN99047
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
Fig.50 Ringer start-up; capacitor charged before start-up means Rtrickle Fig.51 Application example; UBA2051, left part Fig.52 Application example; UBA2051, right part TABLE TABLE TABLE TABLE TABLE TABLE Pinning UBA2050(A)/51(A:C) definitions Resistor options P-MOST line interrupter properties Low-cost line interrupter properties Gain boost selection
Application UBA2050(A)/51(A;C) One-Chip Telephone
INTRODUCTION
Application Note AN99047
UBA2050, UBA2050A, UBA2051, UBA2051A UBA2051C (called general: UBA2050(A)/51(A;C)) offer speech line interface functions, dialling ringer functions required electronic telephone sets. They perform interface between telephone line transducers such microphone capsule, earpiece buzzers. transmission part range TEA106x- TEA111x-family. contain also dialler circuit DTMF pulse dialling. integrated supply with internal voltage regulator supplies dialler available supply point external use. This report gives detailed description UBA2050(A)/51(A;C) which starts block diagram these discussing every detail sub-blocks chapters Chapter describes application example with measurement results e.g. start-up line disconnect behaviour. Also behaviour taken into account described chapter Hints printed circuit diagram given chapter application cookbook chapter helps developer adjust application. UBA2051(A) focused this report. This contains extra features compared UBA2050(A). Also some parts supported UBA2050(A) will described.
NOTE: values parameters given this application note accurate possible, please, refer latest product specification latest ones.
BLOCK DIAGRAM
DP/FL
DTMF
UBA2050(A)/51(A;C) DIALLER
REGULATOR FLASH PULSE DTMF INDICATION EARPIECE BOOST AMPLIFIER
TRANSMISSION
KEYBOARD DETECTOR
KEYTONE
MUTE RECEIVE AMPLIFIER
TONE GENERATOR
DTMF/ RINGER
SLPE
TRANSMIT AMPLIFIER
XTAL CE/CSI CE/FDI
TIMING/ CONTROL
RINGER
DETECTOR/ GENERATOR SUPPLY
MDY/TONE
MIC+ MIC-
SLPE
Fig.1 Block diagram UBA2050(A)/51(A;C)
Refer Fig.2 TABLE concerning pinning UBA2050(A) UBA2051(A;C)
Application UBA2050(A)/51(A;C) One-Chip Telephone
MICMIC+ UBA2050(A)
Application Note AN99047
MICMIC+ UBA2051(A;C)
SLPE DTMF XTAL DP/FL CE/CSI CE/FDI MDY/TONE
SLPE DTMF XTAL DP/FL CE/CSI CE/FDI MDY/TONE
DMO/LED
DMO/LED/KT
Fig.2 UBA2050(A)/51(A;C) pinning
TABLE Pinning UBA2050(A)/51(A;C) Name Description
SLPE DTMF XTAL DP/FL CE/CSI CE/FDI MDY/TONE positive line terminal slope resistance) adjustment line voltage regulator decoupling receiving amplifier input automatic gain control line-loss compensation DTMF transmit input stabilized dialler/ringer part supply oscillator input dial pulse flash output (active LOW) dial mode output (UBA2050/51) DTMF mode indication output (active HIGH) (UBA2050A/51A) keytone output (UBA2051C) chip enable cradle switch input chip enable frequency discrimination input melody (ringer) output DTMF generator output keytone output (UBA2050(A)) keyboard input output (UBA2051(A;C))
Name
Description
keyboard input output keyboard input output keyboard input output keyboard input output keyboard input output keyboard input output keyboard input output negative line terminal earpiece amplifier output
gain adjustment earpiece amplifier
MIC+ MIC-
receive amplifier output non-inverting microphone amplifier input inverting microphone amplifier input supply transmission part peripherals
three main functions Fig.1, transmission, dialler ringer, briefly described. given values typical values nominal conditions. gain factors transmit receive amplifier internally fixed. Consult data sheet necessary.
Application UBA2050(A)/51(A;C) One-Chip Telephone
TRANSMISSION PART
Application Note AN99047
transmission part contains regulator, receive amplifier, earpiece boost amplifier, transmit amplifier combined with LN-SLPE voltage stabilizer, circuit, DTMF input attenuator supply part.
regulator: Delivers stabilized voltage dialler transmission mode well ringer mode. consumes fixed current from Output follows voltage
stabilizer functions shunt stabilizer ringer mode keep input current into delivered ringing signal ringer stage. voltage stabilizer (LN-SLPE) supplied this mode; about
Receive amplifier: Transfers receive signal from input output with voltage gain 33.4 Output drives earpiece boost amplifier. input impedance
DTMF tones applied DTMF amplifier input attenuated coupled into receive amplifier during DTMF dialling.
Earpiece boost amplifier: receive signal from receive amplifier coupled into earpiece boost amplifier which drives earpiece. (initial) gain from output output between means resistors between between adaptating resistor network amplifier offers gain boost from relative initial gain. Transmit amplifier: Inputs MIC+ MIC- with input impedance outputs transmit amplifier SLPE which modulate line current, flowing from SLPE. DTMF signal coupled into transmit amplifier during DTMF dialling while MIC+ MIC- inputs disabled.
microphone gain from inputs 44.2 RSLPE ZSET Zline microphone gain controlled block. DTMF gain from DTMF
LN-SLPE voltage stabilizer: Stabilizes Vref VLN-SLPE 4.15 Vref increased means resistor connected between SLPE Vref decreased means resistor connected between stabilizer decoupled CREG. electronic coil function realised between which equivalent inductance value CREG RSLPE internal resistance 17.5
preferred value RSLPE Changing RSLPE will affect settings, characteristics, transmit, receive sidetone characteristics lower audio frequencies. audio frequency range impedance between much more than impedance ZSET, defined impedance between line terminals B/A, made means external network (resistor complex network) connected between capacitively connected GND.
AGC: function controls gain receive transmit amplifier function line current when connected (directly external RAGC resistor) compensate line losses. DTMF input attenuator: required adapt DTMF levels different country requirements. DTMF gain from DTMF measures supply: Provides supply internal circuitry transmission part from VCC. This voltage supply derived from voltage means pass filter. This supply point also used supply external circuits e.g. electret microphone. Internal current consumption 1.25
Application UBA2050(A)/51(A;C) One-Chip Telephone
DIALLER PART
Application Note AN99047
dialler part takes care system control, system settings generation detection various signals. dialler offers 32-digit Last Number Redial (LNR). Only UBA2051(A;C) supports repertory numbers direct indirect) digits.
Timing/control: Consists resonator-controlled on-chip oscillator, internal reset circuit state determinator. 3.579545 quartz-crystal ceramic resonator connected XTAL. oscillator starts when reaches operation voltage level with CE/CSI HIGH CE/FDI HIGH.
reset circuit monitors power supply voltage level determines whether internal reset signal will generated avoid unknown state circuit. Depending status pins CE/CSI CE/FDI state will entered left: STAND-BY (on-hook), ON-LINE (off-hook) RINGER state. When both CE/CSI CE/FDI LOW, internal reset signal will generated.
Keyboard detector: Scans keyboard max. keys. keyboard connected pins C1-C4 R1-R4. only available with UBA2051(A;C). detected key-press results operation. Multiple pressed keys same time will detected. resistors options will read from pins C1-C3 R1-R4 start-up keyboard detector. Keytone generator: Produces keytone with duration when entry becomes valid. keytone available with UBA2050(A) UBA2051C output. Pulse dialler: Generates number pulses corresponding with pressed ([0] [9]), except which characterized pulses, drive external line current interrupter. Pulses present DP/FL output.
output activated during pulse dialling enable external hardware decrease voltage over telephone line during `make periods'. This output only intended UBA205x UBA205x(A;C).
Flash generator: Makes DP/FL output specific time during flash operation. flash time resistor options. Mute controller: Mutes transmit receive amplifiers transmission part during pulse DTMF dialling well flash operation. DTMF indication (LED driver): Indicates DTMF dialling mode making output HIGH. pulse dialling mode during access pause operation output remains LOW. Only UBA205xA offers this feature. Tone generator: Generates kind signals: DTMF (Tone) signals during DTMF dialling programmable melody (MDY) RINGER state which transmitted DTMF/Ringer multiplexer available MDY/TONE output.
During DTMF dialling, simultaneously tones generated. MDY/TONE output connected DTMF input transmission part external attenuation network. RINGER state, (square-wave) ringer melody will produced. ringer melody supplied ringer output stage. Melodies selected using keys [4].
DTMF/Ringer multiplexer: Selects generated signals MDY/TONE output (melody signal (MDY) tone signal (TONE)). depends following states: RINGER state (using signal) ON-LINE state (using TONE signal). attenuator: Attenuates generated melody from tone generator. Four ringer volume levels supported when using keys [8]. They correspond attenuation values
Application UBA2050(A)/51(A;C) One-Chip Telephone
RINGER PART
Application Note AN99047
ringer part contains ringer detector, also named ringer discriminator, melody generator. ringer will only activated when CE/CSI LOW, CE/FDI provided with ringer signal dialler STAND-BY state. frequency discriminator evaluates checks frequency incoming ringer signal. ringer melody with tones sequence will generated after detection validation ringer signal.
Application UBA2050(A)/51(A;C) One-Chip Telephone
DESCRIPTION
Application Note AN99047
Basic Application UBA2051(A)
basic application UBA2051(A) shown Fig.3. components names refer basic application shown Fig.51 Fig.52. circuit diagram demonstration board OM5840[3] considered basic application. contains features except keytone that UBA2050(A)and UBA2051C offer.
cradle switch TELEPHONE LINE CE/FDI interrupter
DP_FL CE/CSI ringer output stage receive attenuator anti side-tone network CREG RSLPE RAGC SLPE DTMF MIC- MIC+ gain setting bandpass filter Vzln
CVCC
attenuator bandpass filter HAND
CVDD
DP_FL dtmf active CE/CSI CE/FDI attenuator
UBA2051(A)
keypad resistor options
XTAL DP/FL DMO/LED CE/CSI CE/FDI MDY/TONE
Fig.3 Principle basic application Fig.51 Fig.52
Application UBA2050(A)/51(A;C) One-Chip Telephone
TRANSMISSION PART
Application Note AN99047
curves shown this section result from measurement typical samples using schematic shown Fig.3.
3.1.1
characteristics supply blocks
Principle operation UBA2050(A)/51(A;C) generates stabilized voltage (called Vref) between pins SLPE. This reference voltage, typically 4.15 temperature compensated. voltage used internal regulator generate stabilized Vref voltage decoupled capacitor CREG connected GND. transmission, UBA2050(A)/51(A;C) must have resistance current high impedance speech signals. CREG capacitor combination with RSLPE realizes equivalent (internal) inductance between resulting impedance RSLPE approximation external network between (RCC Fig.4) audio frequencies. voltage SLPE proportional line current with offset supply current. This general configuration shown Fig.4.
Isup from preamp Rgasint
internal circuitry
Rline Iline Rexch
Cvcc
regulator
Vexch
SLPE Islpe Rslpe
Cvdd
Creg
Fig.4 Supply configuration
regulates line voltage between pins SLPE. voltage calculated Vref RSLPE ISLPE ISLPE Iline ISUP Iline line current ICC= current consumption supply current peripherals connected ISUP current consumed regulator
Application UBA2050(A)/51(A;C) One-Chip Telephone
000.0E+0 20.0E-3 VREF
Application Note AN99047
Vref
40.0E-3
60.0E-3
80.0E-3 100.0E-3 120.0E-3 140.0E-3 Iline
Fig.5 VLN, Vref versus line current
line current Iline flowing into telephone determined Vexch, Rexch, Rline voltage across telephone including diode bridge. voltages VLN, Vref versus line current shown Fig.5. Below threshold line current (typically mA), Vref automatically adjusted lower value (down absolute minimum voltage 1.45 This means that more sets operate parallel.
000.0E+0
Vref
2.0E-3 VREF
4.0E-3
6.0E-3
8.0E-3
10.0E-3 Iline
Fig.6 voltage behaviour
line currents below this threshold current, UBA2050(A)/51(A;C) reduced sending receiving performances, moreover voltage current ISUP reduced. This called voltage area indicated Fig.6
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
internal circuitry UBA2050(A)/51(A;C) supplied from which derived from line voltage means resistor (RCC). transmission receive signals this supply point must decoupled capacitor (CVCC). Fig.7 shows current consumption (ICC) function supply voltage.
1.4m Vcc[V]
1.2m
1.0m
800.0u
600.0u
400.0u
200.0u User: cadadm
Simulation date: 15-10-98, 00:00:00
VCCIcc[A]
Fig.7 Current consumption transmission part versus
Adjustments performances reference voltage, Vref, adjusted means external resistor Rva. increased connecting resistor between pins SLPE, decreased connecting resistor between pins (see Fig.8). Reduction line voltage reduces peripheral supply capabilities: must least 0.35 higher than (VDD typically). ensure correct operation, advised adjust Vref value lower than higher than (the maximum operating voltage must guaranteed application well safe operating temperature IC). These adjustments will slightly affect parameters: there will small change temperature coefficient Vref slight increase spread this voltage reference matching between internal external resistors. Furthermore, resistor connected between will slightly affect impedance (see section "set impedance").
Application UBA2050(A)/51(A;C) One-Chip Telephone
14:55:45
Application Note AN99047
Vref(V)
LN_REG SLPE_REG
Rreg2
Rreg1
10.0 100.0 User: Simulation date: 16-10-98, 00:00:00 1.0k 10.0k Rva[Ohm]
Fig.8 Adjustment Vref means Rreg2 Rreg1
slope voltage influenced RSLPE resistor. preferred value RSLPE change RSLPE will affect more than characteristics, also influences gains, characteristics, maximum output swing line voltage area threshold Ith.
Application UBA2050(A)/51(A;C) One-Chip Telephone
3.1.2 Supply
Application Note AN99047
Fig.9 indicates supply, current switch voltage stabilizer.
Isup
IDDext
SENSE
Switch
Cvdd
Cvcc
Fig.9 Supply configuration
Principle operation voltage VCC, with reference, supply voltage internal circuitry UBA2050(A)/ 51(A). derivated from VLN, which contains line signal, (low pass) filtered CVCC. mall current drawn from supply peripheral circuits. However, high internal resistance this supply point supply possibilities rather limited. internal current consumption UBA2050(A)/51(A) depends static part ICC, shown Fig.7, dynamic part Irec consumed earpiece amplifier drive earpiece. Irec depends signal swing across earpiece impedance earpiece mainly. Depending setting resistance RCC, small current available external use, taking into account minimum minimum voltage difference between SLPE Both values minimum working voltages available current approximated follows: (ICC Irec) with Irec voltage adjustable means Vref; Fig.8. Think about country requirements mask) resistance network between justify impedance
Application UBA2050(A)/51(A;C) One-Chip Telephone
peak voltage across earpiece impedance earpiece IP(max) [VLN VCC(min) (ICC Irec(max)) RCC] nominal settings (Vref 4.15
Application Note AN99047
4.35 Iline Iline VCC(min) Iline Iline Irec(max) mV-peak across earpiece (RL) based specified VQR(max) load continuously signal across earpiece maximum available current using fixed value ICC. Advised maximum load current from VCC, external use, Adjustments performances impedance connected between also determines impedance, easiest increase current capability supply point increase reference voltage Vref, VLN, connecting resistor between pins SLPE (see 3.1.1). However, refer country requirements masks) about possibility increase and, please, take into account that: weak supply point load currents less than minimum supply level about difference between VSLPE more than over whole line current range
Application UBA2050(A)/51(A;C) One-Chip Telephone
3.1.3 Supply
Application Note AN99047
Principle operation regulated supply internal dialler used supply external circuitry. dependency from line voltage VLN, function line current, follow, also Fig.10:
000.0E+0
:VDD :VDD 0.35 :VDD
2.0E-3
4.0E-3
6.0E-3
8.0E-3
10.0E-3 Iline
Fig.10 versus line current
indicated Fig.9, transistors conduct line current either GND: when voltage higher than current supplies VDD, when voltage lower than line current rerouted when voltage between both transistors conducting order minimize distortion. When equals constant current ISUP (4.5 typically Iline sunk from This constant current doesn't affect return loss value taken into account characteristic. maximum current drawn from VDD, supply external circuitry, depends operation mode. speech mode maximum current available (2.6 maximum) while DTMF mode less current available (1.9 maximum) because enlarged current consumption dialler. pulse dialling mode maximum output current reduced because interrupted input current ISUP correlation with VLN. ringer mode, works shunt regulator shunt regulator able sink between shown Fig.11.
Application UBA2050(A)/51(A;C) One-Chip Telephone
10.0E-9 100.0E-9
Application Note AN99047
ringer mode
trickle mode
1.0E-6
10.0E-6 100.0E-6
1.0E-3
10.0E-3 100.0E-3
Fig.11 versus input current trickle mode well ringer mode
trickle mode (on-hook condition) supplied from line high ohmic resistor save memory contents. this mode current consumption shunt regulator reduced minimum. maximum (specified) current consumption current consumption shunt stabilizer trickle mode (VDD also shown Fig.11.
Application UBA2050(A)/51(A;C) One-Chip Telephone
3.1.4 impedance
Application Note AN99047
Principle operation UBA2050(A)/51(A;C) behaves like equivalent inductance that presents impedance (RSLPE) high impedance (RP) speech signals. integrated resistance order 17.5 +/-15%. parallel with external realized CVCC. Thus, audio frequency range, impedance (between GND) mainly determined resistor. Fig.12 shows equivalent schematic impedance.
Internal
Vref
Cregx Rslpe internal resistor
SLPE
Rslpe
Creg
Cvcc
Fig.12 Equivalent impedance
Adjustments performances When decreasing reference voltage Vref resistor connected between REG, this resistor parallel with (see Fig.12) slightly modifying impedance. complex impedance required, resistor replaced complex network (see Fig.52: Rset1 Rset2 Cset). resistance, which influences value VCC, becomes Rset1 Rset2.
Application UBA2050(A)/51(A;C) One-Chip Telephone
3.1.5 Microphone amplifier
Application Note AN99047
Principle operation Fig.13 shows block diagram microphone amplifier.
from DTMF
MIC+ MIC-
Zline
circuit
Rgasint
Rexch
SLPE Rslpe
Creg
Cvcc
Cexch
Fig.13 Microphone channel
microphone amplifier symmetrical high input impedances (typically between MIC+ MIC-). input this microphone amplifier able handle signals mVrms with less than total harmonic distortion. seen from Fig.13, microphone amplifier itself built parts: preamplifier which realizes voltage current conversion, end-amplifier which realizes current voltage conversion. overall gain (Gvtx) microphone amplifier from inputs MIC+/MIC- output given following equation: Gvtx Avtx Avtx 2.65 (Rgasint Rrefint) ((Ri// |Zline|) RSLPE) with: Rgasint internal resistor realizing current voltage conversion (typically 29.5 with spread +/15%) Rrefint internal resistor determining value internal PTAT tail current source (typically 7.25 with spread matched with Rgasint)
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
impedance fixed network between (RCC this example) parallel with (typically 17.5 Zline load impedance line during measurement gain control (AGC) factor varying from Iline Iline when function applied (see chapter 3.1.7 details) Using these typical values equation Zline find gain equal Gvtx Avtx 44.2 Iline microphone input stage will disabled during DTMF pulse dialling.
Adjustments performances Fig.14 shows frequency response microphone amplifier microphone signal mVrms different ambient temperatures. General conditions are: Iline Zline
13:21:22
|Gain| (dB)
Gmin25
45.0 44.8 44.6 44.4
75°C 50°C
25°C
44.2 44.0 43.8 43.6
-25°C
43.4 43.2 43.0 100.0 1.0k Freq[Hz] User: cadadm Simulation date: 15-10-98, 00:00:00 10.0k
Fig.14 Frequency response microphone amplifier different temperatures
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
Fig.15 shows distortion line signal versus signal swing line currents. increase distortion caused clipping output stage (between SLPE) while increase distortion, about Vrms, caused microphone input stage.
15mA 70mA Output level (Vrms)
Fig.15 Distortion line signal
Fig.16 shows noise level line (psophometrically weighted: curve) versus line current nominal gain when resistor connected between inputs MIC+ MIC-.
15:11:30
-76.0 Noise[dBmp]
-77.0
-78.0
-79.0
-80.0 15.0m 25.0m User: Simulation date: 15-10-98, 00:00:00 35.0m 45.0m 55.0m 65.0m 75.0m 85.0m Iline[A] 95.0m
Fig.16 Microphone noise versus line current
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
Fig.17 shows common mode rejection ratio microphone signals kHz. curves presented. shows spectrum signal when (differential) microphone signal applied MIC- while MIC+ short circuited GND, other shows spectrum when (common) microphone signal applied pins MIC- MIC+ connected together. CMRR more than shown means difference curves kHz.
(dBV)
dBV_comm dBV_diff
-20.0
differential
-40.0
-60.0
common
-80.0
-100.0
-120.0 1.0k User: cadadm Simulation date: 15-10-98, 00:00:00 2.0k 3.0k 4.0k 5.0k Freq[Hz]
Fig.17 Common mode rejection ratio microphone
Application UBA2050(A)/51(A;C) One-Chip Telephone
3.1.6 Receive amplifier block
Application Note AN99047
Principle operation Fig.18 shows block diagram receive channel.
INTERNAL MUTE MUTE/
Rgarint
DTMF
Re21 Re23 Re22
Vcc/2
Fig.18 Receive channel
seen from Fig.18, receive amplifier block built three parts: preamplifier which realizes voltage current conversion followed end-amplifier which realizes current voltage conversion output earpiece amplifier with output gain from internally fixed while gain from externally determined. preamplifier a-symmetrical high input impedance (typically between pins GND. earpiece amplifier UBA2050(A)/51(A;C) able drive loads down impedance while receive amplifier only drive loads down output capability suitable several kind earpieces drive either dynamic, magnetic piezo-electric earpieces. case magnetic dynamic earpieces, capacitor series required decoupling. overall gain Gvrx receive amplifier from input output given equation: Gvrx Avrx Avrx 2.53 Rgarint/Rrefint with: Rgarint internal resistor realizing current voltage conversion (typically with spread +/-15%) Rrefint internal resistor determining value internal PTAT current source (typically 7.25 with spread matched with Rgarint) gain control factor varying from Iline Iline when function applied (see chapter 3.1.7 details) Using these typical values equation, find gain equal Gvrx Avrx 33.4 Iline receive channel will disabled during DTMF pulse dialling.
Application UBA2050(A)/51(A;C) One-Chip Telephone
Adjustments performances
Application Note AN99047
gain earpiece amplifier (from adjusted between this purpose, Fig.18 shows ways setting this gain. gain 33.4 from compensates attenuation approximately provided anti-sidetone network resulting overall gain about from external capacitors CGAR (connected between CGARS (connected between GND) ensure stability earpiece amplifier when relationship CGARS CGAR fulfilled. capacitor CGAR provides first order pass filter, which cut-off frequency determined with RE2. Furthermore, high-pass filter required capacitor inserted series with RE1. Fig.19 shows frequency response typical gain receive amplifier from different temperatures.
|Gain| (dB)
Gmin25
34.0
33.8
33.6
|75°C|
33.4
|25°C| |0°C|
33.2
|-25°C|
33.0 100.0 1.0k Freq[Hz] User: Simulation date: 15-10-98, 00:00:00 10.0k
Fig.19 Receive gain versus frequency: influence temperature
maximum output swing versus distortion output depends general total gain from gain settings earpiece amplifier output signal will clipped output stage. maximum output swing about mVrms which corresponds input signal 12.5 mVrms maximum line current (max. AGC). higher gain settings output signal will clipped output stage about mVrms output load gain earpiece amplifier affected AGC.
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
Fig.20 shows distortion earpiece signal versus output swing load line current gain setting.
11:58:07
THD(%)
12.0 V_THD450 V_THD150 10.0
100.0m User: Simulation date: 16-10-98, 11:55:35 200.0m 300.0m 400.0m 500.0m Output level (Vrms) 600.0m
Fig.20 Distortion earpiece signal load
Fig.21 shows noise loaded with (psophometrically weighted: curve) function line current with gain earpiece amplifier measured with open input Take into account that noise proportional gain setting earpiece amplifier. noise contribution from line, with anti-sidetone network connected input neglected.
-83.0 Noise[dBVp] -84.0
-85.0
-86.0
-87.0
-88.0
-89.0
-90.0
-91.0 15.0m 25.0m User: Simulation date: 16-10-98, 00:00:00 35.0m 45.0m 55.0m 65.0m Iline[A] 70.0m
Fig.21 Noise level across earpiece gain setting open input
Application UBA2050(A)/51(A;C) One-Chip Telephone
3.1.7 Automatic gain control
Application Note AN99047
Principle operation UBA2050(A)/51(A;C) features automatic line loss compensation. automatic gain control varies gain microphone receive amplifiers accordance with line current. enable this function, must connected GND. line currents below current threshold, Istart (typically mA), gain control factor equal giving maximum value gains Gvtx Gvrx. this threshold current exceeded, gain control factor reduced then gains controlled microphone receive amplifiers also reduced. When line current reaches other threshold current, Istop (typically mA), gain control factor limited minimum value equal 0.5, giving lower value microphone receive controlled gains. gain control range both amplifiers typically which corresponds approximately line length (0.5 twisted pair copper) with attenuation dB/km. attenuation correlated current IAGC sunk AGC: when this current lower than typically gains maximum, when this current higher than typically gains minimum. This current proportional voltage between pins SLPE GND. contains internal resistor which sets Istart Istop. adding resistor externally series (between pins GND) reduces IAGC increases values Istart Istop. Adjustments performances UBA2050(A)/51(A;C) used with different exchange supply voltages different feeding bridge resistances. this purpose, resistor RAGC, inserted between pins GND. This RAGC resistor increases both threshold currents Istart Istop proportionally. Fig.22 shows control microphone gain versus line current different values RAGC. When function required, must left open, then control factor remains over line current range.
1998 12:19:44
gain (dB)
45.0 V_AGC0 V_AGC10 V_AGC15 V_AGC22 V_AGC27 43.0 44.0
42.0
RAGC
41.0
40.0
39.0
38.0 15.0m 25.0m User: Simulation date: 16-10-98, 12:14:54 35.0m 45.0m 55.0m 65.0m 75.0m 85.0m
Iline(A)
Fig.22 microphone gain versus line current different RAGC values
Application UBA2050(A)/51(A;C) One-Chip Telephone
3.1.8 DTMF amplifier
Application Note AN99047
Principle operation Fig.23 shows block diagram DTMF channel. INTERNAL MUTE MUTE/
from receive preamp
Rgarint
DTMF
Vcc/2
Zline
from microphone preamp Rgasint
Rexch
SLPE
Cvcc Rslpe
Cexch
Fig.23 DTMF channel UBA2050(A)/51(A;C)
DTMF amplifier asymmetrical high input impedance typically between pins DTMF GND. input biased GND, when input DTMF signal polarized GND, decoupling capacitor necessary. DTMF amplifier built parts: preamplifier which realizes voltage current conversion same end-amplifier microphone amplifier. applied DTMF channel. overall gain (Gvmf) DTMF amplifier from input DTMF output given following equation: Gvmf Avmf Avmf =0.246 (Rgasint Rrefint) ((Ri// |Zline|) RSLPE) with: Rgasint internal resistor realizing current voltage conversion (typically 29.5 with spread +/15%) Rrefint internal resistor determining current internal current stabilizer (typically 7.25 with spread matched with Rgasint)
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
impedance fixed network between (RCC this example) parallel with (typically 17.5 Zline load impedance line during measurement Using these typical values equation Zline find gain equal Gvmf Avmf Furthermore, DTMF signal attenuated transferred receive amplifiers confidence tone. Fig.24 shows frequency response DTMF amplifier different ambient temperatures.
|Gain| (dB)
Gmin25 26.8 26.6 26.4 26.2 27.0
|80°C| |25°C| |-25°C|
26.0 25.8 25.6 25.4 25.2 25.0 100.0 1.0k Freq[Hz] User: Simulation date: 16-10-98, 00:00:00 10.0k
Fig.24 DTMF gain versus frequency: influence temperature
THD(%)
THD[
800.0m
600.0m
400.0m
200.0m
10.0m User: 20.0m 30.0m 40.0m 50.0m 60.0m 70.0m 80.0m 90.0m 100.0m 110.0m Vin[Vrms]
Simulation date: 16-10-98, 00:00:00
Input level (Vrms)
Fig.25 Distortion DTMF line signal versus input signal DTMF
input DTMF amplifier handle signals mVrms with less than THD. Fig.25 shows distortion line versus input signal Iline DTMF signal generated dialler part (MDY/TONE output) attenuated before offered DTMF input.
Application UBA2050(A)/51(A;C) One-Chip Telephone
3.1.9 Internal MUTE
Application Note AN99047
internal MUTE function UBA2050(A)/51(A;C) realizes electronic switching between speech mode dialling mode. dialling mode, both microphone receive channels disabled while DTMF channel enabled. speech mode microphone receive channels enabled while DTMF channel disabled.
3.1.10
Anti-sidetone networks
Principle operation avoid microphone signal return back with high level receive channel, anti-sidetone circuit uses microphone signal from SLPE (which opposite phase) cancel microphone signal input receive amplifier. anti-sidetone bridge already used TEA111x TEA106x) families conventional Wheatstone bridge shown Fig.26 used design anti-sidetone network.
Rast1
Zline
Zbal
Zline
Rast2
Rslpe SLPE
Rast1
Rslpe Rast3 SLPE Zbal
Fig.26 Wheatstone bridge (left) TEA111x family anti-sidetone bridge (right)
TEA111x TEA106x) family anti-sidetone bridge advantage relative flat transfer function audio frequency range between input output both with real complex impedances. Furthermore, attenuation bridge receive signal (between pins independent value chosen Zbal after impedance been fixed condition shown equation fulfilled. Therefore, re-adjustment overall receive gain necessary many cases. Compared previous one, Wheatstone bridge advantages needing resistor less smaller capacitor Zbal. disadvantages include dependence attenuation bridge value chosen Zbal frequency dependence that attenuation. Moreover, input stage introduce some distortion high signal levels. This requires some readjustment overall receive gain.
TEA111X family bridge
anti-sidetone circuit composed //Zline, Rast1, Rast2, Rast3, RSLPE Zbal. Maximum compensation obtained when following conditions fulfilled: RSLPE Rast1 (Rast2 Rast3) [Rast2 (Rast3 RSLPE)] (Rast1 RSLPE) Zbal Zline
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
scale factor chosen meet compatibility with standard value capacitor Zbal. practice, Zline varies strongly with line length line parameters. Consequently, value Zbal chosen with average line length giving acceptable sidetone suppression short long lines. suppression further depends accuracy with which Zbal equals this average line impedance. Example theoretical equivalent average line impedance shown Fig.27.
1265
Fig.27 Equivalent average line impedance
compatibility capacitor value Zbal with standard capacitor value from series (220 nF): 0.636 Rast2, value 3.92 been chosen. using previous equations, calculate Zbal, Rast1, Rast3. find Rast1 Rast3 Zbal series with attenuation receive line signal between derived from following equation: (ZIR Rast2) [Rast1 (ZIR Rast2)] Rast2 (Rast3 Zbal). With values used this example, gives kHz. receive amplifier input impedance, typically
Wheatstone bridge
conditions optimum suppression given Zbal (Rast1 RSLPE) (RCC Zline) Also, this bridge type, value Zbal chosen that corresponds with average line length. attenuation received line signal between given (ZIR Rast1 [Zbal (ZIR Rast1 Ra)] used adjust bridge attenuation; value influence balance bridge.
Application UBA2050(A)/51(A;C) One-Chip Telephone
DIALLER PART
Application Note AN99047
also Fig.1
3.2.1
Timing/Control
behaviour Timing/Control function depends conditions XTAL, CE/CSI CE/FDI pins during start-up (off-hook action) line disconnect (on-hook action, flash unexpected line breaks). handles also several states entered left: STAND-BY, ON-LINE RINGER state. reset delay time will also processed Timing/Control function detecting line breaks. complete handshake protocol between Timing/Control function remaining circuitry avoids contents loss when disabled again CE/FSI= CE/FDI= LOW. external 3.579545 quartz-crystal ceramic resonator connected between XTAL GND. Depending CE/CSI CE/FDI pins operating state entered. After determining state reaching operating voltage level VDD, oscillator starts. Actions such ringer generation, dialling, programming, line disconnect executed depending ringer signal, line break, cradle switch and/or entry.
One-pin oscillator
time base UBA2050(A) UBA2051(A;C) provided on-chip oscillator which consists oscillator circuit with build-in load capacitance, amplitude control, schmitt-trigger circuit output buffer. oscillator completed connecting quartz-crystal ceramic resonator between XTAL GND. Generating correct DTMF tones, crystal 3.579545 type while ceramic resonator types from Murata 3.58 Kyocera 3.58 preferred. oscillator starts when reaches operating level with CE/FDI HIGH CE/CSI HIGH.
Start-up after off-hook
telephone starts follows (see Fig.51 Fig.52; functionality CE/CSI CE/FDI): Cradle switch switched (e.g. handset lifted), makes CE/CSI input HIGH RCSI. Line voltage offered base this switch conducts activates TR1. line current will then flow through providing supply power whole application. dialler initialized internal reset signal. After reset reaching minimum operating voltage oscillator running Timing/Control function monitors status CE/CSI CE/FDI determining which state will entered: ON-LINE RINGER. this case only CE/CSI input HIGH that ON-LINE state entered. dialler performs memory integrity check. case failing check, whole memory cleared. Before resistor option read, dialler waits "pins C1-C4 R1-R4 HIGH". Moreover, resistor options read cycle performed parallel with memory integrity check. telephone operational used conversation dialling.
Fig.28 shows start-up dialler after switching cradle switch Iline supply capacitors CVCC, Cfeed, CVDD, CREG CVRR discharged before start-up. Take into account that clamped about immediately after start-up. During normal telephone with UBA2050(A)/51(A;C) CVDD capacitor will continuously charged (trickle current) therefore even faster start-up dialler achieved.
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
CE/CSI XTAL
Iline
CE/CSI
oscillator signal (ac)
CE/FDI
-1.0 -100.0m 100.0m 200.0m 300.0m 400.0m time(sec)
Fig.28 Dialler start-up after off-hook
Start-up incoming ringer signal
telephone performs following procedure when incoming ringer signal applied CE/FDI input: current into delivered ringing signal. regulator acts shunt stabilizer keep Vtyp. provides supply power dialler part. dialler initialized internal reset signal. After reset reaching minimum operating voltage oscillator running Timing/Control function monitors status CE/CSI CE/FDI determining which state will entered: ON-LINE RINGER. this case CE/CSI input CE/FDI provided with pulses ringer signal. RINGER state entered after evaluating this signal. dialler performs memory integrity check. case failing check, whole memory cleared. Before resistor option read, dialler waits "pins C1-C4 R1-R4 HIGH". Moreover, resistor options read cycle performed parallel with memory integrity check. parallel with resistor options read cycle memory integrity check, ringer detector checks validation ringer signal conforming ringer specification before ringer melody will generated. This detect valid ringer signal soon possible
Fig.29 Fig.30 show start-up dialler after when first ringer signal Vrms offered terminals. already charged approx. means Rtrickle from Vexch Take into account that will charged when node becomes stabilised; Fig.50. oscillator starts after about while signal ringer stage available after supply voltage (VDD trip level) determines start-up ringer this case. supply capacitor CVRR discharged before start-up.
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
Ringer sound produced after receiving ringer signal least ringer periods, after VDD-minimum reached, ringer frequency evaluation.
CE/FDI XTAL
CE/FDI
oscillator signal
-1.0 -50.0m 50.0m 100.0m 150.0m 200.0m time(sec) 250.0m
Fig.29 Dialler start-up incoming ringer signal; VDD, CE/FDI oscillator signal
MDY/TONE
MDY/TONE
-1.0 -50.0m 50.0m 100.0m 150.0m 200.0m time(sec) 250.0m
Fig.30 Dialler start-up incoming ringer signal; signal
Application UBA2050(A)/51(A;C) One-Chip Telephone
Line disconnect
Application Note AN99047
inputs CE/CSI CE/FDI more than reset delay time (typ. internal reset pulse will generated dialler will into STAND-BY state again. will occur when there line-break handset back cradle there ringer signal. current retention delivered telephone line high ohmic resistor Rtrickle (see Fig.51). retention current will smaller than specified blocks inside UBA2050(A)/51(A;C) including oscillator stopped require power supply. Only supply voltage monitor using current. task line-break detector monitoring line voltage. When line-break occurs dialler will interrupt current task after reset delay time. necessary actions will completed before entering into STAND-BY state, avoid damaging contents internal abruptly stopping dialler. Only when supply capacitor CVDD goes below trip level actions stopped immediately. Fig.31 shows line disconnect dialler when handset goes on-hook. oscillator stops after CE/CSI went LOW.
CE/CSI XTAL
Iline
CE/CSI oscillator signal (ac)
CE/FDI
-1.0 -100.0m 100.0m 200.0m 300.0m 400.0m 500.0m 600.0m time(sec)
Fig.31 Dialler line disconnect
Changing STAND-BY state prevented when flash activated. detector will suppressed because duration selectable flash times (300 longer than reset delay time. After flash period timer will start again. Keep mind that supply capacitors this case have supply dialler peripherals least (flash reset delay time ms).
3.2.2
Pulse dialler
pins DP/FL responsible pulse dialling flash function. These connected line interrupter respectively stage. Flash function will realised using same interrupter. Several break/ make ratios flash times selected means resistor options.
Application UBA2050(A)/51(A;C) One-Chip Telephone
Pulse dialler
Application Note AN99047
pulse dialling system uses line current interruptions signal digits dialled exchange. number line current interruptions corresponds digit dialled except digit which characterized interruptions. Digits such entered keyboard converted into pulses which available DP/FL output. Pulse sequences start with pre-digit pause followed sequence pulses corresponding present digit then inter-digit pause duration 10pps. pulse dialler activated when pulse mode selected means resistor option PTS. dialling, transmission part muted only confidence clicks audible earpiece. application possible feed generated keytones (UBA2050(A)/51C) into earpiece (See Fig.43).
Flash generator
flash function, when pressed results calibrated pulse which drives electronic line current interrupter DP/FL. This also used pulse dialler. possible flash generator pulse dialler same time. They depend digit sequence.
UBA2051 used enable external hardware which decreases voltage over telephone line during pulse dialling. Several countries require this feature. will also activated during flash period.
Timing selection
Each pulse starts with line break (mark) followed line make (space). Selection made make/break ratio number pulses second: 1:2/2:3 resp. 10/20 pps. TABLE selection. Flash interruption times depend resistor options (see TABLE Four times possible: After every flash interflash pause inserted recover power supply dialler part (e.g. case multiple flashes).
3.2.3
Tone generator
MDY/TONE operating states: RINGER state valid incoming ringer signal ringer melody (square-wave) with four different volumes will generated this pin. next sections more information about. ON-LINE state ON-LINE state, dialler converts keyboard inputs such digits [9], into data on-chip DTMF generator. Fig.32. Tones transmitted MDY/TONE output. Each digit corresponds combination tones, four possible resp. three HIGH group frequencies. output simultaneous tones generated levels typical -12.6 HIGH group -14.7 groups. harmonic contents fulfil CEPT recommendations. Generation tones only possible when tone dialling mode ON-LINE state selected.
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
REGISTER
DIGITAL SINE WAVE SYNTHESIZER
RINGER ATTENUATOR MDY/TONE
SWITCHEDCAPACITOR BANDGAP VOLTAGE REFERENCE
SWITCHEDCAPACITOR LOW-PASS FILTER
LOW-PASS FILTER
CONTROL
REGISTER
DIGITAL SINE WAVE SYNTHESIZER
Fig.32 Block diagram DTMF generator
3.2.4
output
UBA2051A able drive when connected LED. output becomes active HIGH cases: pulse dialling mode (set with resistor option RPTS) when first DTMF code sent after switching [P->T] [*/T]. tone dialling mode (resistor option RPTS removed) when pressed first DTMF code sent.
output will remain during directly after reset. output able source from when sufficient supply current available from VDD.
3.2.5
Keyboard
Pins C1-C4 R1-R4 connect keyboard which keys mounted. matrix, keys connected ground (GND). advantage this arrangement compared traditional keyboard reduction that obtained same amount keys. Furthermore settings called resistor options read these pins C1-C3, R1-R4 without additional enabling read operation. This possible thanks special port functionality. UBA2050(A), available because dialler memory repertory numbers.
Keyboard structure
UBA2051(A;C) supports keyboard structure shown Fig.33. UBA2050(A), repertory-related keys supported. left side this figure, resistors placed select resistor options. will explained following sections.
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
STORE FTSA FTSB P->T LNR/P
Fig.33 Keyboard structure
keys [*/T] [P->T] have same function during pulse mode RMMS). allows set-maker make choice which keys will used during design-in phase.
Functional keys
meaning each described TABLE TABLE definitions Keys Definition [0-9], [*/T], Digits [*/T], [P->T] Switch over DTMF dialling (mixed mode dialling) [LNR/P] Last Number Redial this first pressed after going off-hook [LNR/P] Access Pause this first pressed after going off-hook [M1-M3] Direct repertory numbers [MEM] Indirect repertory numbers Recall (flash function) [STORE] Memory programming
Keyboard scanning principle
order fulfil requirements some countries choice this matrix keyboard which detects double pressed this case inhibiting DTMF signal line. other hand keyboard supports roll-over feature. example, second entry will reject first entry next entry becomes valid when other keys released again. entry becomes valid after specified debounce time avoid wrong entry interpretation behaviour mechanical switches. principle keyboard debounce procedure consists parts, first debounce detection time second real detection. Approximately required this procedure. debounce procedure release keys vice versa.
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
keyboard controller takes care several cases: when key, single multiple keys pressed. Special attention paid keys connected because they different from remaining keys keyboard with relation scanning detection procedure.
Keytone generator
keytone generated each time valid pressed. keytone frequency duration This feature only offered UBA2050(A) UBA2051C. output push-pull output. buzzer connected between this output taking into account from point max. sourced output current when sufficient supply current available from
3.2.6
Resistor options
User options selected means resistors which externally connected between pins R1-R4, C1-C3 GND. options read these pins without additional enabling read operation. Special port functionality makes this possible.
Resistor options settings
According TABLE number options selected. Each resistor value connected GND. TABLE Resistor options
Resistor FTSA FTSA C2(2)
Function flash time select flash time select [*/T] definition make/break ratio select access pause time select pulses second pulse/tone select
Condition FTSB FTSB
ON(1) [*/T] 33/66 seconds pulse mode
OFF(1) [*/T] [P->T] 40/60 seconds DTMF mode
Note: option resistor present; option resistor present belongs resistor option FTSB.
options only scanned keys pressed keyboard. After each reset dialler scans keyboard repeatedly until keys released. Next, reads translates resistor options into system parameters which will maintained during whole off-hook period. changing resistor options this period influence dialler.
Scanning principle
During directly after reset scanning procedure keyboard option resistors will performed. this state pins C1-C4, R1-R4 LOW. After reset dialler starts monitor pins CE/CSI CE/FDI before entering different operating states described datasheet [1].
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
Next, keyboard pins become HIGH dialler waits releasing possible pressed keys before scanning resistor options started.
INPUT OUTPUT
Fig.34 C1-C4, R1-R4 Input/Output stage configuration
pins R1-R4 C1-C4 connected internally port pull-up source currents: typically (IOH2) (IOH1). current source selected during resistor options read achieve voltage drop across high ohmic resistor, when applied, with respect thresholds logic levels. level means that resistor option present. resistor options scanned translated into system parameters which stored. (IOH1) used keyboard scanning during whole off-hook period suppress presence option resistors relation with voltage keyboard pins. This voltage will reach nearly voltage. pressed will force this level zero this case.
3.2.7
Dialling procedures
APPENDIX gives description dialling procedures. They categorized into: Dialling with Store repertory Dialling from repertory actions dial outputs same symbols which described beginning this appendix.
Application UBA2050(A)/51(A;C) One-Chip Telephone
RINGER PART
Application Note AN99047
pins CE/CSI, CE/FDI MDY/TONE take care generation ringer signal ringer stage.
3.3.1
Ringer input frequency measurement
ringer signal offered CE/FDI input UBA2050(A)/51(A;C). half-wave rectified that dialler easily detect zero-crossing, especially high frequencies square wave shaped ringer signals. ringer circuitry becomes active incoming ringer frequencies more than frequency threshold. This frequency threshold adjusted externally. ringer signal valid when following conditions met: fring CE/CSI ringer signal duration frequency cycles (max. threshold levels: level high level CE/FDI input used activate initialize dialler part notified that CE/CSI input evaluation ringer signal otherwise dialler will enter ON-LINE state. Before dialler circuit evaluate check ringer signal, powered ringer signal, available terminals, VDD. regulator functions shunt stabilizer keep capacitor CVDD should able keep voltage level when ringer voltage drops between signal bursts.
3.3.2
Melody Volume
When ringer signal valid, MDY/TONE output delivers melody. This melody follows cadence ringer signal. signal MDY/TONE square wave. Four different melodies available which selected using keys (only during ringing). melody frequency duration given table "Ringer melodies" datasheet [1]. Only basic DTMF frequencies used. signal level ringer melody output MDY/TONE controlled using keys [8]. These (peak peak) levels corresponding voltage levels across buzzer with attenuation respectively typically. last selected melody (keys [4]) ringer volume (keys [8]) will stored used again when dialler enters RINGER state again. important that voltage level remains above even when dialler been STAND-BY state. Otherwise previous stored settings lost.
Application UBA2050(A)/51(A;C) One-Chip Telephone
APPLICATION EXAMPLE
Application Note AN99047
application example also described this report. This example general purpose application exchanges with voltage regulation. exchanges with current regulation (European TBR21 requirement) [4]. possible hardware stages such DTMF indication (LED driver), stage gain boost drawn application diagram. set-maker develop user-specified telephone quickly composing UBA2050(A)/51(A;C) with more stages. Only some fine tuning required fulfil specific country requirements. Demonstration board OM5840 good example this application. this chapter functionality this board explained evaluated. UBA2050(A)/51(A;C) denotes types UBA2050, UBA2050A, UBA2051, UBA2051A, UBA2051C. Unless specified, these types will hereafter referred UBA2051. case that hardware stage described this chapter appropriate type should used proper connection.
Description application
application example low-cost basic telephone shown Fig.51 Fig.52. build with UBA2051 transmission/dialler/ringer discrete ringer output stage with buzzer. interconnections between both figures indicated. application offers following features: High performance line interrupter low-cost line interrupter) Transmission functions with adjustable parameters described transmission part chapter Pulse, DTMF mixed mode dialling, redial, 13-number repertory dialling specified ref. Ringer signal detection melody generation function output DTMF dialling indication Gain boost Keytone generation (not shown separately explained)
application build around UBA2051. individual settings UBA2051 impedance minimum operating voltage (VDD) dialler part dialling. several blocks application briefly described this chapter. Details concerning performances given section 4.2.
Polarity guard protection
diode bridge applied transmission part well ringer stage ensure proper functioning independently polarity line voltage respectively rectify ringer signal. Protection against excessive current surges achieved break-over diode (BR211_220) between A-B/B-A terminals. current limiter Rprot provides protection against current surges exceeding about designed continuous limitation line current. According UBA2050(A)/51(A;C) specification, voltage most pins transmission part exceed about prevent this voltage regulator diode (BZD23C_10 connected between GND. limits also this voltage during start-up higher line currents mA). voltage across ringer output stage limited about means zener diode diode Vtyp UBA2051. limited shunt stabilizer UBA2051 Vtyp.
Application UBA2050(A)/51(A;C) One-Chip Telephone
High performance line interrupter
Application Note AN99047
view lowest DC-mask, high performance line interrupter applied this application. interrupter directly controlled DP/FL output UBA2051. DP/FL output from dialler open drain output high-impedance when reset dialler active. When goes off-hook using cradle switch (S1), line current flows through resistor Rprot P-MOST TR1. this situation gate-source voltage negative P-MOST conducts. TABLE shows properties interrupter. TABLE P-MOST line interrupter properties Advantages Disadvantages powerless switching handling required ohmic on-resistance higher cost than bipolar lowest DC-mask vendors adjustable over-current protection influence impedance base current loss voltage drop across interrupter shown Fig.35. calculated line current times onresistance interrupter measuring about including protection resistor. This voltage drop increases total slope-resistance (RSLPE about interrupter influence impedance relative ohmic on-resistance from LINE relative high ohmic control circuitry between LINE VEE.
TRANS
cost Transistor interrupter
800.0m
600.0m
P-MOST interrupter
400.0m
200.0m
20.0m 40.0m 60.0m 80.0m 100.0m Iline
(mA)
Fig.35 Voltage drop across interrupters, including Rprot resistor
Application UBA2050(A)/51(A;C) One-Chip Telephone
Low-cost line interrupter
Application Note AN99047
low-cost line interrupter made according Fig.36. transistor-driven line interrupter consisting transistors TR1, TR2, resistors
LINE
MPSA92
100k
MPSA92
S1-2 CRADLE BF420
470k DP/FL
Fig.36 Low-cost line interrupter
off-hook small current will flow through when DP/FL HIGH. Consequently, conduct. impedance will affected ohmic value value high possible. However, enough keep into saturation over whole line current range. decreases switch-off time interrupter. TABLE shows properties interrupter.
TABLE Low-cost line interrupter properties Advantages Disadvantages cost high voltage drop line currents many vendors affects impedance transistor extra Line current interruption achieved level DP/FL. DP/FL output from dialler open drain output high-impedance when reset dialler active. voltage drop across this type interrupter function line current also shown Fig.35.
Speech transmission
transmission part UBA2051 stabilizes voltage between SLPE. delivers supply voltage internal connected electret microphone. Also integrated VDD-regulator supplied from delivers supply dialler part possible connected peripherals. buffered CVCC while buffered CVDD. impedance will mainly determined impedance network between VCC. This application impedance about realised Rset1
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
Rset2 applied Cset. complex impedance realised means complex network Rset1, Rset2 Cset. Take into account increased resistance between complex networks which decreases supply performance VCC. application intended with electret microphone dynamic earpiece. another electret microphone requires modification application. attenuation between microphone adapted network: Rtx1, Rtx2, Rtx3, Ctx1 Ctx2. Earpiece gain adjustable gain boost network: RGAR1, RGAR2, Cgb, Rgb1, Rgb2 Rgb3. Microphone earpiece arrangements detailed described ref. [1]. Buffer capacitor CVCC discharged rapidly during break periods pulse dialling with result that buffer capacitor CVDD will charged during these periods.
Oscillator
UBA205x types have oscillator with integrated load capacitance typ. 18pF (Cosc) typical negative resistance (Rosc). resonator (crystal ceramic) connected between XTAL GND. generating correct DTMF tones, resonator should 3.579545 type. Connecting ceramic type will give more frequency deviation, still fulfil requirements (Murata 3.58 Kyocera 3.58 MSA). When using ceramic resonator, additional components required depending upon ceramic resonator specifications (refer product type specification). connecting pico-farad parallel with resonator oscillation frequency decreased. connecting pico-farad series with resonator, oscillation frequency increased. specified ceramic resonator following formulas used calculate oscillation frequency (see Fig.37):
Resonator
XTAL
UBA2051
Im(Zxtal) Cosc Re(Zxtal) =Rosc
Fig.37 Resonator equivalent circuit connected oscillator.
Oscillation will only occur when Rosc series resistance resonator negative. However this internal Rosc affected resonator. calculate remaining Rosc following procedure must used.
Application UBA2050(A)/51(A;C) One-Chip Telephone
series circuit Xosc, Rosc transformed into parallel circuit
Application Note AN99047
Im(Zxtal) Xosc Re(Zxtal) =Rosc
Rosc Xosc Xosc -Rosc
Fig.38 Series parallel transformation
influence resonator parallel resistance capacitance (=Xp) added Suppose that resonator manufacturer guarantees minimum value (not relevant quartz-crystal) maximum value
Fig.39 Correction
corrected parallel circuit transformed back into series circuit
Fig.40 Parallel series transformation
oscillation should negative. EXAMPLE: UBA2051: Cosc Rosc Resonator: (Murata CSA3.58MG [9]) 360.6 40.32 5.99
fosc 3.596039 +0.46% Xosc j2459; j1098 j1010 -142.3 negative therefore oscillation will occur.
Application UBA2050(A)/51(A;C) One-Chip Telephone
Dialler/Ringer
Application Note AN99047
dial parameters dialler part UBA2051 resistor options specific-country requirements. single contact keyboard connected I/Os named R1-R4, C1-C4. Without repertory facility UBA2050(A) used. Consequently, repertory-related keys (STORE, MEM, have removed. Reset performed internal reset UBA2051. Output DP/FL drives interrupter perform pulse dialling (set with resistor option RPTS) flash function. position cradle switch determines CE/CSI level during STAND-BY state (CE/CSI LOW) ON-LINE state (CE/CSI HIGH). Input CE/FDI connected line network Cring, RFDI detect operation state UBA2051 combination with CE/CSI. Frequency discriminator network RFDI combination with threshold CE/FDI input detects ringer signal from line with minimum frequency minimum ringer voltage Vrms. Output MDY/TONE delivers melody ringer circuit ringer mode) DTMF dialling signal DTMF input transmission part conversation mode) attenuator Cdtmf, Rdtmf1 Rdtmf2 shown Fig.41. capacitor blocks component. calculated attenuation 19.4 which input impedance DTMF also taken into account. load external attenuator output MDY/TONE very large with respect output impedance MDY/TONE) tone generator.
Dialler part
UBA2050(A)/51(A;C)
Transmission part
MDY/TONE
Cdtmf
Rdtmf1 Rdtmf2 2.74k
DTMF
100nF
Fig.41 DTMF attenuation network
Ringer circuit
ringer signal from line available CE/FDI input UBA2051 capacitor Cring, zener diode resistors RFDI Only positive swing ringer signal offered this pin. minimum ringer voltage depends network threshold CE/FDI input approximately Vrms. voltage discriminator (Z4, RFDI takes care this voltage. When CE/FDI provided with valid ringer pulses (frequency level) CE/CSI kept dialler part enters RINGER state immediately. this, capacitor should kept charged during STAND-BY state speed-up initialization dialler part incoming ringer signals. Supply ringer stage delivered ringer signal from exchange diode-bridge series network Cring-Rring. supply voltage ringer stage limited zenerdiode This diode cascaded with diode regulator resulting VRR-max energy stored into supply capacitor CVRR. ringer buzzer driven three transistors TR6. capacitive behaviour buzzer, will charged discharged repeatedly means transistors resp. TR5. volume ringer sound controlled means keys amplitude control MDY/TONE signal. basic adjustment ringer sound done resistor RVOL. Resistor RMDY limits current from MDY/TONE. Furthermore, ringer melody changed means keys [4].
Application UBA2050(A)/51(A;C) One-Chip Telephone
stage
Application Note AN99047
UBA2050 UBA2051 (not UBA2051(A;C)) supports (dial mode output) function pulse dialling mode. mode resistance respectively voltage between terminals reduced. stage shown Fig.51 consists zener diode MOSFET (TR7) resistor RDMO. changing zener diode other voltage type, voltage between lines during pulsed digit adjusted. circuitry driven output dialler. This output push-pull output when reset dialler activated. conducts when output HIGH. voltage between terminals will about when stage activated.
arrangements
connection arrangements shown Fig.42 which applied with A-version only UBA205XA family.
UBA205XA UBA205XA
Fig.42 arrangements
(low current type) supplied directly from output when sufficient supply current available from (max.1.9 mA). other case, used supply means current source shown right hand diagram Fig.42. This circuit influence impedance. Both circuits available application Fig.51 Fig.52, selectable jumpers.
Gain boost selection
described datasheet [1], earpiece gain from between (see Fig.18). Resistor adjusts gain from while network RE21, RE22 RE23 replaces this resistor boost gain from Resistor preferred value gain between fixed 33.4 Take into account that sidetone network attenuates receive signal from input with gain boost network shown Fig.52 boost attenuate earpiece gain using jumpers J10. TABLE shows gain boost selection. overall voltage gain range from Refer more information about gain boost calculation.
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
Jumper placed None Only Only Only
TABLE Gain boost selection Gain Gain -5.6 18.2 -1.6 7.15 +2.4 3.65 +6.4
dynamic earpiece handset connected between terminals EAR+ EAR-.
Keytone buzzer
keytone output only available with UBA2050(A) UBA2051C. keytone signal made audible ways shown Fig.43 which supported application Fig.51 Fig.52. According Fig.43, keytone buzzer connected directly output keytone signal coupled into receive path make audible earpiece. UBA2050(A)/51C
Dialler part Dialler part
UBA2050(A)/51C
Transmission part
Buzzer
other components
Fig.43 Keytone arrangements
left handed option, max. delivered buzzer when sufficient supply current available from VDD. Buzzer KPE-167 from Kingstate PKM34EW from Murata applied. right handed solution cheapest that uses only components. Components values based cut-off frequency important high value resistor otherwise gain receive path will affected.
4.2.1
Settings performance application behaviour
settings
voltage A/B-B/A terminals result voltage drop across UBA2051, line interrupter diode bridge. voltage drop across UBA2051 depends setting reference voltage (Vref) between SLPE voltage drop across RSLPE which depends line current.
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
Important minimum line voltage (A/B-B/A) minimum supply voltage required dialler. supplied which depends resistors Rreg1 Rreg2. Both resistors placed application change Vref; resulting default value Vref 4.15 A-B/B-A voltage measures line current, while stabilized DTMF well pulse dialling achieved. level will below stabilised level breakperiods during pulse dialling flash. Fig.44 shows line voltage VA/B across A/B-B/A terminals function line current Iline with Rreg2 placed well with Rreg2
10.0 VA/B VA/B
Rreg2
Rreg2 placed VA/B
10.0 20.0 30.0 40.0 50.0 60.0 70.0 80.0 90.0
Iline (mA)
100.0
Fig.44 Line voltage across function line current
Supply possibilities
used supply peripherals electret microphone. possibilities rather limited depend general LN-SLPE setting, resistance network between total current consumption from VCC. also possible supply peripherals VDD. Max. output current because dialler part also supplied from requires current when generating DTMF tones. dialling functions, DTMF pulse dialling, operational according specification down Iline about while transmit receive possible down about STAND-BY state (on-hook) repertory numbers have stored. minimum specified memory retention. Consult Fig.11 internal current consumption levels. Providing supply achieved series network: Rtrickle, S1-2, adjusted exchange with voltage Depending requirements resistor Rtrickle modified provide less more current from line on-hook state. Remark: during on-hook, peripherals influence memory retention! Therefore during on-hook peripherals should drain current from VDD.
Application UBA2050(A)/51(A;C) One-Chip Telephone
4.2.2 Transmission
Application Note AN99047
impedance
impedance realised with Rset1 while complex impedance complex network between realised. Fig.45 shows (dB) `600 set' measured with reference. same graph given (dB) `complex set' consisting Rset1 Cset Rset2 measured with reference impedance this case, value CREG increased reach
40.0 ohms complex 35.0
Zset: real Zref CREG
30.0
25.0
20.0
15.0
|Zset Zref| |Zset Zref| 10.0
Zset: complex Zref CREG
BRL(dB)
100.0 1.0k
freq. (Hz)
5.0k
Fig.45 application example `real' `complex' termination
Send receive
This application intended with electret microphone. total gain from microphone terminals line measures impedance line load without activated function. internal gain setting 44.2 typical, while attenuation about achieved network (Ctx1, Ctx2, Rtx1, Rtx2, Rtx3), input impedance (Zi(MIC)) components (C103 C104). maximum swing line signal measures 10%) over frequency range 3400 impedance, line load line current. capacitor (Cint) placed between gate-source keep conducting negative swings line signal. improves maximum swing line signal lower frequencies. overall receive gain from line earpiece about earpiece impedance This attenuation from line input, internally determined gain receive stage 33.4 typically (externally adjustable) gain earpiece amplifier -6.4 gain values given without activated function without gain boost. Depending jumpers (shown Fig.52), overall receive gain determined. "Gain boost selection" page
Application UBA2050(A)/51(A;C) One-Chip Telephone
Side tone
Application Note AN99047
Reproduction (electrical) microphone signal earpiece reduced anti-sidetone circuit consisting components Rast1, Rast2, Rast3, Rbal1, Rbal2 Cbal. principle applied TEA111x TEA106x) family bridge given chapter 3.1.10 fully described [6]. case applied (pin open) anti-sidetone circuit re-calculated mean cable length Re-adjustment balance circuit necessary other cable types, different line length, etc.
4.2.3
Dialling
DTMF dialling
DTMF signal from MDY/TONE output dialler part attenuated network Rdtmf1, Rdtmf2 Cdtmf applied DTMF input transmission part. During dialling signal amplified DTMF stage transferred line resulting total level approx. impedance line load. gain DTMF stage typical.
Pulse dialling Flash
line current will interrupted electronic interrupter (TR1) under control DP/FL signal. During break-periods dialled digit flash) UBA2051 supplied stored energy CVCC CVDD because they will charged during these periods. value buffer capacitors CVCC CVDD have value resp. keep supply level Fig.46 shows voltage A/B-B/A terminals, supply voltages line current during dialling digit [8]; Vexch Fig.47 shows during maximum selectable FLASH time voltage reduced about
VA/B
50.0
VA/B VA/B
30.0 40.0
20.0
10.0
Iline
-100.0m 100.0m 200.0m 300.0m 400.0m 500.0m 600.0m 700.0m 800.0m time(sec) 900.0m
Fig.46 Behaviour during pulse dialling digit
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
VA/B
50.0
VA/B
40.0
30.0
20.0
10.0
IIline
-100.0m 100.0m 200.0m 300.0m 400.0m 500.0m 600.0m 700.0m 800.0m time(sec) 900.0m
Fig.47 Behaviour during flash
4.2.4
Start-up Disconnect
Off-hook start-up
Fig.48 (VLN, VCC, VA/B function time) shows start-up behaviour after off-hook (outgoing call) Iline line current Iline while supply capacitors CREG have been discharged. When Iline starts flowing, voltage will clamped protection zener about When about line voltage stabilizer becomes operational. datasheet more information. After connecting application with line supply very first time, handset lifted charge supply capacitors CVDD. operational within line current. STAND-BY state capacitor CVDD kept charged Rtrickle. current this state more than
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
10.0
1V/div 1V/div 1V/div
50.0
VA/B
Vexch
45.0 40.0
Iline
VA/B
5V/div
35.0 30.0
-100.0m
25.0 20.0 15.0 10.0
VA/B
100.0m 200.0m 300.0m 400.0m time(sec) 500.0m
Fig.48 Start-up after off-hook; IC-voltages line voltage VA/B
Line disconnect
When handset placed cradle (on-hook) dialler ON-LINE state RINGER state dialler will detect line break. After waiting time (the reset delay time) dialler goes into STAND-BY state. will decrease slowly end-level about
Ringer start-up
Fig.49 Fig.50 shows start-up behaviour after ringing burst (incoming call) discharged CVDD capacitor respectively charged CVDD (VDD ringer voltage Vrms CVRR discharged both cases. When ringer voltage goes high, capacitor CVRR starts charging capacitor Cring, resistor Rring diode bridge D2-D5. Also voltage capacitor CVDD rises from zener diode diode soon reaches (VPOR; Power Reset level) dialler starts monitors CE/FDI (see Fig.29 Fig.30) whether ringer signal still present.
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
20.0
60.0
VA/B Vring-ac
15.0
40.0
VA/B
20.0
10.0
-20.0 -40.0
-50.0m 50.0m 100.0m 150.0m 200.0m 250.0m 300.0m time(sec) 350.0m -60.0
Fig.49 Ringer start-up; capacitor discharged before start-up
20.0
60.0
VA/B Vring-ac
15.0
45.0
30.0
VA/B 15.0
10.0
-15.0
-30.0
-45.0
-50.0m 50.0m 100.0m 150.0m 200.0m 250.0m 300.0m time(sec) 350.0m -60.0
Fig.50 Ringer start-up; capacitor charged before start-up means Rtrickle
Application UBA2050(A)/51(A;C) One-Chip Telephone
ELECTROMAGNETIC COMPATIBILITY
Application Note AN99047
UBA2050(A)/51(A;C) been designed with on-chip measures keep disturbances away from sensitive circuit parts higher frequencies MHz). lower frequency range (from upwards) coupling into occurs mainly A/B-lines handset cord. Improvement immunity those frequencies realised filtering connectors pins layout which designed with respect EMC. demonstration boards (OM5839 OM5840, resp. [3]) have single-sided wiring with filled ground plane between interconnections. measures are: Filtering from A/B-B/A terminals line input UBA2050(A)/51(A;C) means C100 line terminals, C101 from GND. Filtering from terminals MIC-/MIC+ inputs C105 C107 terminals, series resistors Rtx1 Rtx2 decoupling pins means C103 C104. Filtering from terminal output C106 terminal. Filtering receiver channel input C102. Furthermore bandwidth receiver amplifier limited CGAR stability guaranteed means combination CGAR CGARS. Decoupling capacitor CVDD short connection GND.
General recommendations measures design are: filled ground between wires case single-sided ground plane when double-sided applied. Place line handset connectors close each other same side decouple connections means capacitors. Place capacitors close possible corresponding pins. small size ceramic capacitors. Make interconnection-wires short possible. wire-bridges instead clever design with long wires. Design symmetrical microphone entry from connector inputs
HINTS PRINTED CIRCUIT BOARD LAYOUT
Care must taken avoid that large line current flows into common ground tracks which sensitive points (such amplifier inputs) connected. this reason special attention should paid pins SLPE UBA2050(A)/51(A;C) which conduct almost complete line current. copper tracks connecting external components corresponding IC-pins should kept short possible. ground connection RFI-capacitors should realized means large possible copper planes grids. RFI-capacitors must connected close possible pins that have decoupled. ground plane circuit board must kept large possible where every copper area must connected ground-plane grid) least points. "RF-guard" described chapter realised. example printed circuit board layout UBA2050(A)/51(A;C) found [3].
Application UBA2050(A)/51(A;C) One-Chip Telephone
APPLICATION COOKBOOK
Application Note AN99047
This chapter gives adjustment steps realise basic application with UBA2050(A)/51(A;C). Referring Fig.51 Fig.52, design flow given number steps which should made. possible every step, components involved their influence every step given.
Step Adjustment setting: Adjust setting UBA2050(A)/51(A;C) local requirements. Voltage LN-GND This voltage adjusted changing Vref: increased with Rreg2 resistor between pins SLPE decreased down with Rreg1 resistor between LN). slope might modified changing value RSLPE (this advised: parameters changed too). relative small increase slope realised with resistor series with Depends values Vref resistive part network between (Rset1 Rset2). value adjusted changing value CREG: lower frequencies improved higher value case complex impedance; has, however, negative effect start-up behaviour. current through electret microphone adjusted means resistors Rmicp Rmicm. Extra supply decoupling advised means Rfeed Cfeed.
slope
Supply point
Artificial inductor
Microphone supply
Impedance sidetone: After setting required impedance, sidetone optimized using sidetone network order minimize loop gain line conditions. adjusted that step. impedance adjusted with impedance network connected between (Rset1 Rset2//Cset). Take into account total resistance between VCC. Adjust Zbal (Rbal1, Rbal2, Cbal) according line characteristics. Internally defined, characteristics (Istart Istop) shifted higher line currents with external RAGC resistor connected between GND. case necessary shift Istart Istop lower current values, value RSLPE must increased proportionally (see section 3.2.5; other parameters changed too).
Sidetone
DTMF gain DTMF
network Cdtmf, Rdtmf1 Rdtmf2 determines attenuation before entering DTMF pin. internal DTMF gain fixed.
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
Step Adjustment Microphone receive gains Microphone gain microphone gain application adjusted before entering pins MIC+/MIC- UBA2050(A)/51(A;C). reduced using resistor Rtx3 which forms bridge attenuator with Rtx1 Rtx2. Ctx1, Ctx2 form high-pass filter with Rtx1, Rtx2 series with input impedance MIC+/MIC-. capacitor Cmic (connected between MIC- MIC+ terminals) forms low-pass filter with impedance microphone resistors Rmicp/Rmicm. Earpiece gain earpiece gain application adjusted means resistors RGAR1 RGAR2 without gain boost. capacitor parallel with RGAR1 RGAR2 forms low-pass filter, stability ensured with capacitor CGARS CGAR between pins GND. Ringer stage Ringer voltage Sound level
ringer voltage adjusted means zener diode level adjusted resistor RVOL. ratio between RVOL determines gain. Maximum swing across buzzer depends ringer voltage, gain amplitude MDY/TONE signal (volume control).
stage voltage
voltage mode adjustable with zener diode
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
REFERENCES
Philips Semiconductors DATA sheet UBA2050(A);51(A;C) "One-Chip telephone with speech, dialler ringer functions". Philips Semiconductors User Manual ETT/UM99014, `User manual OM5839: Demonstration board UBA2050(A)', Knubben. Philips Semiconductors User Manual ETT/UM99001, `User manual OM5840: Demonstration board UBA2051(A)', Knubben. Philips Semiconductors Application Note AN96140, `TEA1112 France', Soree. Philips Semiconductors Data Handbook IC03a. "Semiconductors Wired Telecom Systems". Order number: 9397 00839 Philips Semiconductors Data Handbook IC03b. "Semiconductors Wired Telecom Systems". Order number: 9397 00811 Publication 1000-4-6 (formerly 801-6). Electromagnetic compatibility electrical electronic equipment. Part6: Immunity conducted disturbances, induced radio frequency fields above kHz. 1000-4-3 Draft International Standard (Annex Immunity radiated, radio frequency, electromagnetic fields (formerly 801-3). Murata Application Manual "Ceramic resonator (CERALOCKR)", 1997 (P17E10.pdf)
Application UBA2050(A)/51(A;C) One-Chip Telephone
APPENDIX
A/B-B/A CE/FDI CE/CSI DP/FL DTMF Electret Gvrx Gvtx Iled Iline Irec Istart, Istop [M1]-[M3] MIC+/[MEM] OM5839 OM5840 Rast Rexch Rgarint RGAR [STORE]
Application Note AN99047
LIST ABBREVIATIONS DEFINITIONS
Line terminals application example Automatic Gain Control; line loss compensation facility Access Pause Time selection Balance Return Loss Chip Enable Frequency Discriminator Input Chip Enable Cradle Switch Input (Inverted) Dial Pulse FLash output Dual Tone Multi Frequency Electro Magnetic Compatibility Electret microphone with amplifier Ground reference Gain factor receive stage Gain factor transmit stage Current consumption (from VCC) Current through connected between Line current Current consumption receive amplifier Current consumption peripheral devices connected Excess line current from SLPE Start stop currents function Threshold current voltage function Scale factor balance network Light Emitting Diode Artificial inductor voltage stabilizer Make Break ratio Selection Direct memory recall keys Microphone input Indirect memory recall Demonstration board UBA2050(A) Demonstration board UBA2051(A) Printed Circuit Board Pulse Tone Selection Piezo Ceramic Buzzer Element Resistor adjust sidetone bridge attenuation Anti sidetone resistor Radio Frequency Bridge resistance exchange Internal resistance (134 define receive gain External resistance reduce receive gain Internal resistance (17.5k) between Programming mode
Application UBA2050(A)/51(A;C) One-Chip Telephone
TONE VA/B Vref VSLPE Vexch XTAL Zmic Zbal Zset Total Harmonic Distortion Tone generator output Voltage across A-B/B-A line terminals Supply Transmission part peripherals Stabilized supply Dialler Ringer part level (with respect GND) Stabilized reference voltage between SLPE Supply node ringer stage level SLPE Exchange voltage Oscillator input Input impedance receive amplifier Symmetrical input impedance microphone amplifier Balance network reduce side tone impedance between A/B-B/A terminals Gain control factor function; Reference REFERENCE chapter Reference equation
Application Note AN99047
Application UBA2050(A)/51(A;C) One-Chip Telephone
APPENDIX
Application Note AN99047
APPLICATION WITH UBA2051
Rprot BC558 Cint BSP254A BZD23C BZX79C
Rast1 130k 100nF C102 Rast2 3.92k Rast3 2.2nF
C105 2.2nF C106 2.2nF C107 2.2nF MIC+ EAREAR+ MICMIC+ EAREAR+ MIC-
BZX79C
BSN254A
Rdmo 470k 470k 470k
Rbal1
Rbal2 Cbal 220nF BF420
Rslpe
XR_SFR25H XR_SFR25H C101 4.7nF Rreg2
470k S1-2 Rcsi 470k
Rreg1
SLPE
SLPE
S1-1 Rtrickle Cring Rring 2.2k PR02 BR211_220 BAS11 BAS11 C100 2.2nF
Creg LINE 4.7uF Ragc
Rled1 LS3369EH Cvdd 220uF
BC547
3.579545MHz DP_FLn
XTAL
BAS11 BAS11 Rled2
DP_FLn
DMO_LED CE/CSI
DMO_LED
CE/CSI
Rfdi 470k Rdtmf1 220k Rdtmf2 2.74k Cdtmf 100nF
CE/FDI
CE/FDI
BZX79C
MDY_TONE
MDY_TONE
100k BZX79C
BAS45
100k 40V-pp Cvrr 22uF BC557 BC547 BC547
Rmdy 100k
Rvol
Fig.51 Application example; UBA2051, left part
UBA2051(A)
LS3369EH
DTMF
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
Rset1 Rset2 Cset XnF_630 Cvcc 100uF Cfeed 10uF Rmicp Ctx1 18nF Rtx3 8.2k Ctx2 18nF Rtx2 Rmicm MIC+ Rtx1 MICRfeed 3.3k
Rgar1 22.1k Rgar2
Cear C104 2.2nF C630 10uF
22.1k
MIC-
Rgb1 18.2k MIC+ 100k Cgar 100pF UBA2051(A) P->T LNR/P C655 Cgars C103 2.2nF C630 EAR+ EAR-
Rgb2 7.15k
Rgb3 3.65k
GAIN BOOST
STORE
FTSA FTSB
Rmms Rftsa Rftsb Rmbs Rapt Rpps Rpts
PHILIPS
PHILIPS SEMICONDUCTORS PS-SLE TELECOM
Engineer: Knubben Drawn Geraads Changed
henkes
Philips Semiconductors B.V. Eindhoven Netherlands
Sheet Name: DESIGN Size:
OM5840
Project:
UBA2051(A)
Drwg:
Date Changed:
Tuesday, June 1999
Time Changed:
8:00:46
PR47802
Fig.52 Application example; UBA2051, right part
Application UBA2050(A)/51(A;C) One-Chip Telephone
APPENDIX DIALLING PROCEDURES UBA2050/51
Application Note AN99047
SYMBOLS
OFF-HOOK operation ON-HOOK operation D1.Dn digit key: [1], [2], [3], [4], [5], [6], [7], [8], [9], [0], [*], Dp1.Dpn output pulse digit: Dt1.Dtn output DTMF digit: Flash Flash output Pause digit Access pause LNR/P Last Number Redial Pause M1.Mn Direct access memory Indirect memory access [Store] P->T Pulse Tone mode Pulse Tone DTMF P->T from Pulse mode Characters P->T, (pulse mode) selection pulse mode (DTMF mode)PTS selection DTMF mode
Note: keytone generated when pressed successfully processed exept this DTMF digit.
Application UBA2050(A)/51(A;C) One-Chip Telephone DIALLING WITH
Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone: D2,.Dn Dp1, Dp2,.Dpn Dt1, Dt2,.Dtn LNR/P Dp1, Dp2,.Dpn Dt1, Dt2,.Dtn D2,., D32, D33,.Dn Dp1, Dp2,., Dp32, Dp33,.Dpn Dt1, Dt2,., Dt32, Dt33,.Dtn LNR/P nothing nothing D2,., LNR/P,.Dn Dp1, Dp2,.,tap,.Dpn Dt1, Dt2,.,tap,.Dtn LNR/P Dp1, Dp2,.,tap,.Dpn Dt1, Dt2,.,tap,.Dtn D2,., */T, Dy,.Dn Dp1, Dp2,.,tap, Dtx, Dty,.Dtn Dt1, Dt2,., Dtx, Dty,.Dtn LNR/P Dp1, Dp2,.,tap, Dtx, Dty,.Dtn Dt1, Dt2,., Dtx, Dty,.Dtn D2,., P->T, Dx,., */T,.Dn Dp1, Dp2,.,tap, Dtx,., *,.Dtn Dt1, Dt2,.,tap, Dtx,., LNR/P Dp1, Dp2,.,tap, Dtx,., *,.Dtn Dt1, Dt2,.,tap, Dtx,., D2,.Dn, Dp1, Dp2,.Dpn, Dt1, Dt2,.Dtn, LNR/P Dp1, Dp2,.Dpn Dt1, Dt2,.Dtn
Application Note AN99047
n<33
n<33
n>32
n>32
n<33
n<33
P->T
P->T
Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone:
n<32
n<32
Application UBA2050(A)/51(A;C) One-Chip Telephone
Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone: D2,.Dn, Dp1, Dp2,.Dpn, Dt1, Dt2,.Dtn, LNR/P nothing nothing D2,.Dn, Dp1, Dp2,.Dpn, tfl, Dt1, Dt2,.Dtn, tfl, LNR/P tap, tap,
Application Note AN99047
n>31
n>31
LNR/P, tap, tap,
n<31
n<31
D2,.Dn, LNR/P, Dp1, Dp2,.Dpn, tfl, Dpx, tap, Dt1, Dt2,.Dtn, tfl, Dtx, tap, LNR/P nothing nothing D2,., D30, Dp1, Dp2,., Dp30, tfl, Dt1, Dt2,., Dt30, tfl, LNR/P Dpx,.Dpn Dtx,.Dtn
n+4>32
n+4>32
Dx,.Dn Dpx,.Dpn Dtx,.Dtn
*/T, D4,*/T, Dz,.Dn Dp1, Dp2,. tap, Dt4, Dt6, tfl, Dpz,.Dpn Dt1, Dt2, Dt4, *,Dt6, tfl, Dtz,.Dtn LNR/P Dpz,.Dpn Dtz,.Dtn
P->T z)+7)
P->T z)+7)
P->T, D4,*/T, Dz,.Dn Dp1, Dp2,. tap, Dt4, Dt6, tfl, Dpz,.Dpn Dt1, Dt2, tap, Dt4, *,Dt6, tfl, Dtz,.Dtn LNR/P Dpz,.Dpn Dtz,.Dtn
z)+7)
z)+7)
Application UBA2050(A)/51(A;C) One-Chip Telephone
Application Note AN99047
Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone:
D2,., */T, Dx,. Dz,.Dn Dp1, Dp2,., Dpx, Dpy, tfl, Dpz,.Dpn Dt1, Dt2,., #,Dtx, Dty, tfl, Dtz,.Dtn LNR/P Dpz,.Dpn Dtz,.Dtn
z)+y+1)
z)+y-1) z)+y+1) P->T x)+5)
Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone:
D2,.*/T, Dx.,*/T, Dy,.,,*/T, Dz,.Dn Dp1, Dp2,. tap, Dtv, tfl, Dpx,., tap, Dty,. *,Dtz,.Dtn Dt1, Dt2, Dtv, tfl, Dtx,., *,Dty,., Dtz.Dtn LNR/P Dpx,., tap, Dty,. Dtz,.Dtn Dtx,., Dty,., Dtz.Dtn
P->T x)+5)
D2,. ,*/T, Dx.,*/T, Dy,., */T, Dz,.Dn Dp1, Dp2,., Dpv, tfl, Dpx,., Dpy,., Dpz,.Dpn Dt1, Dt2,., Dtv, tfl, Dtx,., Dty,., Dtz.Dtn LNR/P nothing nothing
x)+v+1)
x)+v+1)
STORE REPERTORY
SINGLE PROGRAMMATION
Actions: Dial out: content: Actions: Dial Actions: Dial out: content: Actions: Dial out: D2,.Dn, nothing D2,.Dn LNR/P nothing D2,.Dn, nothing Previous LNR/P nothing n<22
programmation
n>21
Application UBA2050(A)/51(A;C) One-Chip Telephone
Actions: Dial out: content: content: Actions: Dial Actions: Dial out: content: content: Actions: Dial Actions: Dial out: content: content: Actions: Dial D2,., P->T, Dx,., */T, LNR/P,Dy,.Dn, nothing D2,., P->T, Dx,., Dy,.Dn (Pulse mode) D2,., P->T, Dx,., Dy,.Dn (DTMF mode) LNR/P nothing
Application Note AN99047
n<22
D2,., */T, Dx,., */T,.Dn, nothing D2,., P->T, Dx,., *,.Dn D2,., Dx,., *,.Dn LNR/P nothing
(Pulse mode) (DTMF mode)
P->T n<22
D2,., */T, Dx,., */T,.Dn, nothing D2,., Dx,., D2,., Dx,., *,.Dn LNR/P nothing
(Pulse mode) (DTMF mode)
n<22
Actions: D2,., P->T, Dx,., */T,.Dn, MEM, Dial out: nothing MEM4 content: D2,., P->T, Dx,., *,.Dn MEM4 content: D2,., P->T, Dx,., *,.Dn Actions: Dial Actions: Dial out: content: content: Actions: Dial LNR/P nothing
(Pulse mode) (DTMF mode)
n<22
D2,., P->T, Dy,., P->T, Dz,., nothing D2,., P->T, Dy,., P->T, Dz,., (Pulse mode) D2,., P->T, Dy,., P->T, Dz,., (DTMF mode) LNR/P nothing
n<22
CASCADE PROGRAMMATION
Actions: Dial out: content: content: MEM4 content: content: MEM, nothing empty
Application UBA2050(A)/51(A;C) One-Chip Telephone
Actions: Dial out: Actions: Dial out: content: content: Actions: Dial Actions: Dial out: Actions: Dial out: content: Actions: Dial out: LNR/P nothing
Application Note AN99047
P->T, .,Dz, Dp1, Dp2, tap, Dtx, .Dtz LNR/P nothing Dp1,
(Pulse mode)
D2,., P->T, Dp5, D2,., P->T, LNR/P Dp5,
(Pulse mode)
n<22
NOTEPAD
Actions: Dial out: content: conversation D2,.Dn, nothing D2,.Dn n<22
Actions: LNR/P Dial pulse: Dp1, Dp2,.Dpn Dial DTMF: Dt1, Dt2,.Dtn
DIALLING FROM REPERTORY
SINGLE DIALLING
content: Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone: D2,.Dn Dp1, Dp2,.Dpn Dt1, Dt2,.Dtn LNR/P Dp1, Dp2,.Dpn Dt1, Dt2,.Dtn
Application UBA2050(A)/51(A;C) One-Chip Telephone
MEM2 content: D2,.Dn Actions: MEM, Dial pulse: Dp1, Dp2,.Dpn Dial tone: Dt1, Dt2,.Dtn Actions: Dial pulse: Dial tone: LNR/P Dp1, Dp2,.Dpn Dt1, Dt2,.Dtn
Application Note AN99047
content: D2,., P->T, Dy,., P->T, Dz,., Actions: Dial pulse: Dp1, Dp2,., tap, Dtx, tfl, Dpy,., tap, Dtz,., Dial DTMF: Dt1, Dt2,., tap, Dtx, tfl, Dty,., tap, Dtz,., Actions: LNR/P Dial pulse: Dpy,., tap, Dtz,., Dial DTMF: Dty,., tap, Dtz,., content: Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone: D2,., Dx,., *,.Dn Dp1, Dp2,., Dpx,.Dpn Dt1, Dt2,., Dtx,., *,.Dtn LNR/P Dp1, Dp2,., Dpx,.Dpn Dt1, Dt2,., Dtx,., *,.Dtn
CASCADE DIALLING
cascade dialling possible soon previous dialling request elapsed. elapsed, request ignored. content: D2,.Dn MEM2 content: Dx,.Dz Actions: Dial pulse: Dp1, Dp2,.Dpn Dial tone: Dt1, Dt2,.Dtn Actions: Dial pulse: Dial tone:
Dpr, Dtr,
MEM, Dpv, Dpx,.Dpz Dtv, Dtx,.Dtz
LNR/P Dp1, Dp2,.Dpn, Dpr, Dps, Dpv, Dpx,.Dpz Dt1, Dt2,.Dtn, Dtr, Dts, Dtv, Dtx,.Dtz
(z-v)
Application UBA2050(A)/51(A;C) One-Chip Telephone
content: MEM2 content: Dx,.Dz Actions: MEM, Dial pulse: Dp1, Dp2, Dp3, .Dpn Dial tone: Dt1, Dt2,Dt3, .Dtn Actions: Dial pulse: Dial tone: Actions: Dial pulse: Dial tone: LNR/P Dp1, Dp2, Dp3, .Dpn Dt1, Dt2, 3,.Dtn MEM, Dpv, Dpx, .Dpz Dtv, Dtx, .Dtz
Application Note AN99047
LNR/P Dp1, Dp2, Dp3, .Dpn, Dpv, Dpx, .Dpz Dt1, Dt2, Dt3,.Dtn, Dtv, Dtx, .Dtz
(z-v))
content: D4,., P->T, MEM2 content: Dx,.Dz Actions: MEM, Dial pulse: Dp1, Dp2, Dp3, tfl, Dp4,., tap, Dtm, Dtv, Dtx, .Dtz Dial DTMF: Dt1, Dt2, Dt3, tfl, Dt4,., tap, Dtm, Dtv, Dtx, .Dtz Actions: LNR/P Dial pulse: Dp4,., tap, Dtm, Dtn, Dtv, Dtx, .Dtz Dial DTMF: Dt4,., tap, Dtm, Dtn, Dtv, Dtx, .Dtz content: D2,., D15, D16,., MEM2 content: Dx,.Dz Actions: Dial pulse: Dp1, Dp2,., Dp15, tfl, Dp16,., Dp20 Dial DTMF: Dt1, Dt2,., Dt15, tfl, Dt16,., Dt20 Actions: LNR/P Dial pulse: Dp16,., Dt20, Dtv, Dtx, .Dtz Dial DTMF: Dt16,., Dt20, Dtv, Dtx, .Dtz
(z-v)
MEM, Dtv, Dtx, .Dtz Dtv, Dtx, .Dtz
(z-v))
content: Dx,.Dz MEM2 content: D2,., D15, D16,., Actions: MEM, Dial pulse: Dtv, Dtx, .Dtz Dp1, Dp2,., Dp15, tfl, Dp16,., Dp20 Dial DTMF: Dtv, Dtx, .Dtz Dt1, Dt2,., Dt15, tfl, Dt16,., Dt20 Actions: Dial LNR/P nothing (z-v)+21)
Other recent searches
SKY18105 - SKY18105 SKY18105 Datasheet
PC120TX4-140 - PC120TX4-140 PC120TX4-140 Datasheet
LC121S1-A1MT - LC121S1-A1MT LC121S1-A1MT Datasheet
KST13 - KST13 KST13 Datasheet
Privacy Policy | Disclaimer
© 2012 Datasheet Archive
