FWLR Application Note AN-345 purpose this application note p
|
|
|
Top Searches for this datasheet
UniSLIC14 IDT821068 Programmable Octal CODEC
FWLR
Application Note AN-345
purpose this application note provide reference design UniSLIC14 IDT821068 Programmable Octal CODEC. network requirements many countries require analog subscriber line circuit (SLIC) terminate subscriber line with impedance voiceband frequencies which complex, rather than resistive (e.g. 600). UniSLIC14 accomplishes this impedance matching with single network connected pin. IDT821068 Octal CODEC uses integrated programmable realize Impedance Matching, Transhybrid Balance, Frequency Response Correction Gain Setting functions. Discussed this application note following: 2-wire impedance matching. Receive gain (4-wire 2-wire) transmit gain (2-wire 4-wire) calculations. Reference design both +680||0.1µF (China Complex Impedance).
DWFK
Impedance matching UniSLIC14 subscriber load important optimization wire return loss, which turn cuts down echoes voice communication path. also important maintaining voice signal levels long loops. Impedance matching UniSLIC14 accomplished making SLIC's impedance (ZO, Figure equal desired terminating impedance minus value protection resistors (RP). formula calculate proper matching 2-wire impedance shown Equation
With UniSLIC14 programmed match 600, IDT821068 uses intergrated programmable realize impedance.
(EQ.
value with protection resistors is108k. closest standard value 107k.
INTERSIL UniSLIC14 RING
0.47µF RESISTIVE 0.47µF 200(600 2*30) 108k Std. value 107k
FLOATING
Figure IMPEDANCE MATCHING
2000 Integrated Device Technology, Inc.
January 2002
6120
Application Note AN-345
WLYH
Figure shows simplified transmission model UniSLIC14 connection IDT821068 SLIC. Circuit analysis UniSLIC14 yields following design equations:
Node Equation UniSLIC14 input 500k 500k
(EQ. (EQ.
(EQ.
Substitute Equation into Equation
-1000k 500k Loop Equation UniSLIC14 feed amplifier load 500k 500k
(EQ. (EQ. (EQ.
Substitute Equation into Equation
Loop Equation Tip/Ring interface
(EQ.
Substitute Equation into Equation
(EQ.
Substituting -V2W/ZL into Equation rearranging solve results Equation
(EQ.
where: input voltage pin. internal node voltage that function loop current detector impedance matching networks. Internal current SLIC that difference between input receive current feedback current. metallic current. protection resistor (typical 30). external resistor/network matching line impedance. ring voltage output pins SLIC. ring voltage including voltage across protection resistors. line impedance. source impedance SLIC input impedance SLIC including protection resistors.
January 2002
Application Note AN-345
500K
INTERSIL UniSLIC14 500K 500K
IDT821068 VOUT1 VIN1 CHANNEL Filter Filter CHANNEL
RINT
RING
CHANNEL
CHANNEL CHANNEL CHANNEL
Core PCM/GCI Interface
DR1/DD DX1/DU
RINT
500K
1/80K
500K 500K IM(ZTR-2RP) (ZTR 2RP)
CHANNEL CHANNEL
FLOATING
Figure UniSLIC14 SIMPLIFIED TRANSMISSION CIRCUIT IDT821068
HLYH HFHL
4-wire 2-wire gain across UniSLIC14 equal divided input voltage VRX, reference Figure 2.The receive gain calculated using Equation Equation expresses receive gain (VRX V2W) terms network impedances. From Equation value match line impedance (ZL) UniSLIC14 plus protection resistors 2RP). This results 4-wire 2-wire gain shown Equation
HLYH HFHL 6\VWH
(EQ.
receive gain across system defined gain from highway phone (V2W). With receive gain through UniSLIC14 receive gain across system entirely controlled programming IDT821068. IDT821068 program receive gain across system ways (reference Figure first programming signal gain analog form. analog receive gain, also known Digital Analog (D/A) gain, programmed IDT821068 either -6dB. second programming signal gain (via. coefficients) when digital form. digital form receive path programmed from -12dB with minimum 0.1dB steps. This results possible receive gain (D/A) programming range from +6dB -18dB. Note: Analog gain brings less noise than digital gain. When allocating CODEC gain, majority required gain should preformed analog stage. Reference section titled "Information Required Calculate IDT821068 CODEC Coefficients" information obtaining coefficients your design.
January 2002
Application Note AN-345
VPLW $FUR FURV QL6/
2-wire 4-wire gain equal VTX/EG with reference Figure
Loop Equation
(EQ.
From Equation with
(EQ.
Substituting Equation into Equation simplifying.
(EQ.
design, -VTR, therefore,
(EQ.
more useful form equation rewritten terms /V2W. voltage divider equation written convert from shown Equation
(EQ.
Rearranging Equation terms substituting into Equation results equation 2-wire 4-wire gain that's function synthesized input impedance SLIC protection resistors (ZTR).
(EQ.
match line, 107k/200+60) where equal 30.0. This results 2-wire 4-wire gain 0.915dB 595-60/595). Notice that phase 2-wire 4-wire signal phase with input signal that gain will always less than because protection resistors.
VPLW $FUR 6\VWH FURV 6\VWHP
transmit gain across system defined gain from phone 2-wire side (V2W) highway. Setting gain IDT821068 will have account attenuated signal through UniSLIC14. system gain entirely controlled programming IDT821068. IDT821068 program transmit gain across system ways (reference Figure first programming signal gain analog form. analog transmit gain, also known Analog Digital (A/D) gain, programmed IDT821068 either +6dB. second programming signal gain (via. coefficients) when digital form. digital form transmit path programmed from -6dB +12dB with minimum 0.1dB steps. This results possible transmit gain (A/D) programming range from -6dB +18dB. Note: Analog gain brings less noise than digital gain. When allocating CODEC gain, majority required gain should preformed analog stage. Reference section titled "Information Required Calculate IDT821068 CODEC Coefficients" information obtaining coefficients your design.
January 2002
Application Note AN-345
INTERSIL UniSLIC14 RING
CHANNEL 0.47µF VOUT1 Analog Gain -6dB
IDT821068 Digital Gain +6dB -12dB filter
Receive path
0.47µF VIN1 Analog Gain +6dB CHANNEL Digital Gain -6dB +12dB filter Transmit path DR1/DD DX1/DU
FLOATING
CHANNEL
Core PCM/GCI Interface
Figure RECEIVE GAIN G(4-2), TRANSMIT GAIN (2-4)
EULG %DOD VK\E %DODQ
Transhybrid balance measure well input signal canceled (that being received SLIC) from transmit signal (that being transmitted from SLIC CODEC). Without this function, voice communication would difficult because echo. Transhybrid balancing filter inside IDT821068 used adjust transhybrid balance ensure echo cancellation meets ITU-T specifications. coefficient Echo Cancellation ECF.
UHFW
filter receive path filter transmit path programmed correct frequency distortion caused impedance matching filters. coefficients Frequency Response Correction receive path transmit path.
DWLR WLRQ &2'(&
calculate IDT821068 coefficient, customers should provide following information about their subscriber line card: Accurate SLIC PSPICE model. provided .lib file PSPICE schematic file. System Impedance Gain (Transmit path Receive path) Using coefficients provided IDT, overall performance system will pass ITU-T requirements. When button selected from Operation General Interface screen, Operation screen will appear (Figure From this screen, user configure coefficients current channel.
January 2002
Application Note AN-345
Figure COEFFICIENT OPERATION SCREEN
'HVLJ 'HVLJQ QL6/
design criteria follows: 4-wire 2-wire gain (DR1/DD V2W) equal 2-wire 4-wire gain (V2W DX1/DU) equal Figure gives reference design using Intersil UniSLIC14 IDT821068 Programmable Octal CODEC. Also shown Figure voltage levels specific points circuit.
G4-2
0dBm0(600) 0.7745VRMS 0dBm0(600) INTERSIL UniSLIC14 0dBm0(600) 0.7745VRMS
G2-4
System Requirements: Impedance: Transmit Gain (A/D): Receive Gain (D/A):
IDT821068 Digital Gain Digital Gain +0.9dB
0dBm0(600) 0.7745VRMS
0.7745VRMS CHANNEL 0.47µF VOUT1 Analog Gain Analog Gain CHANNEL
RING 0.47µF FLOATING
Receive path DR1/DD DX1/DU
VIN1
Transmit path
CHANNEL -0.915dBm0(600) 0.69714VRMS
Core PCM/GCI Interface
REFERENCE TABLE COEFFICIENTS
0dBm0(600) 0.7745VRMS
Figure REFERENCE DESIGN HC55185 IDT821068 WITH 600W LOAD IMPEDANCE
January 2002
Application Note AN-345
SHGD DWFK ,PSH
2-wire impedance matched line impedance using Equation repeated here Equation
(EQ.
line impedance 600, equals:
108k
(EQ.
closest standard value 107k. However, would very convenient cost effective system manufacturers only type line card meet different impedance requirements different gain requirements. programmability IDT821068 help system manufactures reach this goal. using different coefficients this reference design meet both 680||0.1µ impedance requirements. With value selected 107k coefficients different Transmit Gains (A/D) Receive Gains (with line impedance 600) given Tables
HFLI WDWLR 6SHF WLRQ
design criteria China specific solution follows: Desired line circuit impedance 680//0.1µF Receive gain (V2W/(DR1/DD)) -3.5dB Transmit gain ((DX1/DU)/V 0dBm0 defined into complex impedance 1020Hz Figure gives reference design using Intersil UniSLIC14 IDT821068 Programmable Octal CODEC. Also shown Figure voltage levels specific points circuit. These voltages will used adjust gains network.
January 2002
Application Note AN-345
G4-2
-2.19dBm0(600) 0.60196VRMS -2.19dBm0(600) INTERSIL UniSLIC14 0.47µF FLOATING RING 0.47µF VIN1 0.60196VRMS VPWRO+ VOUT1
System Requirements: Impedance: 200+600||0.1µF Transmit Gain (A/D): Receive Gain (D/A): -3.5dB
IDT821068 Digital Gain -2.19dB Digital Gain -0.4dB
0dBm0(600) 0.7745VRMS
CHANNEL Analog Gain Analog Gain CHANNEL
Receive path
Transmit path DR1/DD DX1/DU
CHANNEL
Core PCM/GCI Interface
REFERENCE TABLE COEFFICIENTS
-2.19dBm0(600) 0.60196VRMS -3.1dBm0(600) 0.54176RMS
G2-4
VPCMOUT -3.5dBm0(600) 0.51769VRMS
Figure REFERENCE DESIGN UniSLIC14 IDT821068 WITH CHINA COMPLEX LOAD IMPEDANCE
$GMXVW $GMXVWP
voltage equivalent 0dBm0 into (0dBm0(811)) calculated using Equation (811 impedance complex China load 1020Hz).
0dBm 0.90055V 0.001
(EQ.
gain referenced back 0dBm0(600) equal
0.90055V GAIN 1.309dB 0.7745V
(EQ.
adjustment -3.5dBm0 load referenced
Adjustment 3.5dBm0 1.309dBm0 2.19 (EQ.
voltage load (referenced 600) given Equation23:
2.19 0.60196V (EQ. 0.001
SHGD DWFK ,PSH
With value selected 107k coefficients different Transmit Gains (A/D) Receive Gains (with line impedance 680||0.1µ given Tables
January 2002
Application Note AN-345
TABLE COEFFICENTS, SYSTEM GAINS: (TRANSMIT GAIN (0dB), RECEIVE GAIN (0dB)), CODEC ANALOG GAINS:(TRANSMIT PATH +6dB, RECEIVE PATH 0dB) Coefficient IMF: ECF: ACT: ACR: CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
January 2002
Application Note AN-345
TABLE COEFFICENTS, SYSTEM GAINS: (TRANSMIT GAIN (0dB), RECEIVE GAIN (0dB)), CODEC ANALOG GAINS:(TRANSMIT PATH +6dB, RECEIVE PATH 0dB) Coefficient IMF: ECF: ACT: ACR: CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
January 2002
Application Note AN-345
TABLE COEFFICENTS, SYSTEM GAINS: (TRANSMIT GAIN (0dB), RECEIVE GAIN (-3.5dB)), CODEC ANALOG GAINS:(TRANSMIT PATH +6dB, RECEIVE PATH 0dB) Coefficient IMF: ECF: ACT: ACR: CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient
CHANNEL
January 2002
Application Note AN-345
TABLE COEFFICENTS, SYSTEM GAINS: (TRANSMIT GAIN (0dB), RECEIVE GAIN (-3.5dB)), CODEC ANALOG GAINS:(TRANSMIT PATH +6dB, RECEIVE PATH 0dB) IMF: ECF: ACT: ACR:
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
January 2002
Application Note AN-345
TABLE COEFFICENTS, SYSTEM GAINS: (TRANSMIT GAIN (0dB), RECEIVE GAIN (-7.0dB)), CODEC ANALOG GAINS:(TRANSMIT PATH +6dB, RECEIVE PATH -6dB) Coefficient IMF: ECF: ACT: ACR: CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient
CHANNEL
January 2002
Application Note AN-345
TABLE COEFFICENTS, SYSTEM GAINS: (TRANSMIT GAIN (0dB), RECEIVE GAIN (-7.0dB)), CODEC ANALOG GAINS:(TRANSMIT PATH +6dB, RECEIVE PATH -6dB) IMF: ECF: ACT: ACR:
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
January 2002
Application Note AN-345
TABLE 0.1µF COEFFICENTS, SYSTEM GAINS: (TRANSMIT GAIN (0dB), RECEIVE GAIN (0dB)), CODEC ANALOG GAINS:(TRANSMIT PATH +6dB, RECEIVE PATH 0dB)) Coefficient IMF: ECF: ACT: ACR: CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
January 2002
Application Note AN-345
TABLE 0.1µF COEFFICENTS, SYSTEM GAINS: (TRANSMIT GAIN (0dB), RECEIVE GAIN (0dB)), CODEC ANALOG GAINS:(TRANSMIT PATH +6dB, RECEIVE PATH 0dB)) Coefficient IMF: ECF: ACT: ACR: CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
January 2002
Application Note AN-345
TABLE 0.1µF COEFFICENTS, SYSTEM GAINS: (TRANSMIT GAIN (0dB), RECEIVE GAIN (-3.5dB)), CODEC ANALOG GAINS:(TRANSMIT PATH +6dB, RECEIVE PATH 0dB)) Coefficient IMF: ECF: ACT: ACR: CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient
CHANNEL
January 2002
Application Note AN-345
TABLE 0.1µF COEFFICENTS, SYSTEM GAINS: (TRANSMIT GAIN (0dB), RECEIVE GAIN (-3.5dB)), CODEC ANALOG GAINS:(TRANSMIT PATH +6dB, RECEIVE PATH 0dB)) IMF: ECF: ACT: ACR:
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
January 2002
Application Note AN-345
TABLE 0.1µF COEFFICENTS, SYSTEM GAINS: (TRANSMIT GAIN (0dB), RECEIVE GAIN (-7.0dB)), CODEC ANALOG GAINS:(TRANSMIT PATH +6dB, RECEIVE PATH 0dB) Coefficient IMF: ECF: ACT: ACR: CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
Coefficient
CHANNEL
January 2002
Application Note AN-345
TABLE 0.1µF COEFFICENTS, SYSTEM GAINS: (TRANSMIT GAIN (0dB), RECEIVE GAIN (-7.0dB)), CODEC ANALOG GAINS:(TRANSMIT PATH +6dB, RECEIVE PATH 0dB) IMF: ECF: ACT: ACR:
Coefficient IMF: ECF: ACT: ACR:
CHANNEL
January 2002
Other recent searches
SLP1006P3 - SLP1006P3 SLP1006P3 Datasheet
NJW1168 - NJW1168 NJW1168 Datasheet
NJW1168L - NJW1168L NJW1168L Datasheet
NC7WZ126 - NC7WZ126 NC7WZ126 Datasheet
DS96176RS-485 - DS96176RS-485 DS96176RS-485 Datasheet
RS-422 - RS-422 RS-422 Datasheet
AV109-73 - AV109-73 AV109-73 Datasheet
APTGT150DU170 - APTGT150DU170 APTGT150DU170 Datasheet
AD7545 - AD7545 AD7545 Datasheet
AD7545A - AD7545A AD7545A Datasheet
Privacy Policy | Disclaimer
© 2012 Datasheet Archive
