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Agilent ACPM-7812 CDMA / AMPS Power Amplifier Module

Applications · 800 MHz CDMA handsets · Wireless data terminals

Agilent ACPM-7812 CDMA / AMPS Power Amplifier Module
Data Sheet
Applications · 800 MHz CDMA handsets · Wireless data terminals
Package Circuit Diagram
Pin 6 GND Vdd1
Vdd1 RF Out Pin 5 RF Out RF In Pin 2 RF In
GND Pin 4 Vdd2 Vcntl Pin 3
Vcntl
Bottom View of Package
Absolute Maximum Ratings 1 Parameter
Vdd Supply Voltage Power Dissipation 2 Bias Current Control Voltage (Vcntl) Amplifier Input RF Power Junction Temperature Storage Temperature (case temperature)
Value
Package Marking and Dimensions
Gnd Vdd1
ACPM-7812
RF Out RF in
YYWWDD
Vdd2 Gnd Vcntl
Top View (package with lid cover on top) PCB Side View
Maximum 0.071 (1.8)
.034 (0.86) Bottom View (footprint)
R.020 (R0.51)
Electrical Characterization Information
Parameter
Cellular CDMA
Units
Comments
dBc / 30 kHz dBc / 30 kHz mA
dB dBm / Hz dBc
4.5 -141 -50 -138 All phases
dBc dBc
GAIN (dB)
25 0 5 10 15 Pout (dBm) 20 25 30
-60 0 0.4 0.8 1.2 1.6 2.0 2.4 2.8 Vcntl (V)
0 0 5 10 15 Pout (dBm) 20 25 30
Figure 1. Gain vs. Pout.
Idd (mA)
Figure 2. Gain vs. Vcntl.
Figure 3. PAE vs. Pout.
ACPR1 (dBc)
Idd (mA)
300 200 100 0 0 5 10 15 Pout (dBm) 20 25 30
20 0 0 5 10 Pout (dBm)
15 Pout (dBm)
Figure 4. Idd vs. Output Power.
HARMONIC SUPPRESSION (dBc)
Figure 6. ACPR (885 kHz) vs. Pout.
ACPR2 (dBc)
35 2fo 3fo
GAIN (dB)
-65 -70 -75 -80 -85 -90 0 5 10 15 Pout (dBm) 20 25 30
-55 10 15 20 Pout (dBm) 25 30
Pout (dBm)
Figure 7. ACPR (1.98 MHz) vs. Pout.
Figure 8. 2nd / 3rd Harmonics vs. Pout.
Figure 9. AMPS Gain vs. Pout.
30 20 10 0 10 15 20 25 30 35 Pout (dBm)
Figure 10. AMPS PAE vs. Pout.
Ordering Information Part Number
ACPM-7812-BLK ACPM-7812-TR1
No. of Devices
Container
Bulk 13" Tape and Reel
Tape Dimensions and Orientation
1.50 (min)
ACPM-78xx
PA orientation in carrier tape
Reel Drawing
RECYCLE SYMBOL
18.40 (max.)
ESD Label 76.2 mm x 31.0 mm (See Below)
DETAIL X
RECYCLE SYMBOL C L
DETAIL X
EMBOSSED LINE x2 90 mm Length Lines 147 mm away from center point EMBOSSED "M" 5 mm Height
All dimensions in mm.
Application Information
The following material is presented to assist in general design and use of the APCM-7812. · 3.0V Characterization, for use in Data Card Applications · cdma2000 1XRTT Description and Characterization data · Design tips on various methods to control the bias on Vcntl pin · Description of ACPR measurement methods · Description of Agilent evaluation demoboard for ACPM-7812 · IR Reflow Profile (applicable for all Agilent E-pHEMT PAs)
3.0 V Characterization, Data Card Applications
Parameter
800 MHz CDMA
Units
Comments
dBc / 30 kHz dBc / 30 kHz mA
dB dBm / Hz dBc
4.5 -141 -50 All phases
dBc dBc
100 0 0 5 10 15 Pout (dBm) 20 25 30 0 5 10 15 Pout (dBm) 20 25 30
25 0 5 10 15 Pout (dBm) 20 25 30
Figure 11. Gain vs. Pout.
Figure 12. PAE vs. Pout.
Figure 13. Idd vs. Pout.
ACPR1 (dBc) ACPR2 (dBc)
-50 -55 -60 -65 -70 -75 -80 -85 0 5 10 15 Pout (dBm) 20 25 30 0 5 10 15 Pout (dBm) 20 25 30
HARMONIC SUPPRESSION (dBc)
2fo 3fo
-55 10 15 20 Pout (dBm) 25 30
Figure 14. ACPR (885 kHz) vs. Pout.
Figure 15. ACPR (1.98 MHz) vs. Pout.
Figure 16. 2nd / 3rd Harmonics vs. Pout.
GAIN (dB)
0 -10 -20 -30 -40 -50 0 0.4 0.8 1.2 1.6 2.0 2.4 2.8 Vcntl (V)
Figure 17. Gain vs. Vcntl.
cdma2000 1xRTT Characterization
1.2288Mchip / s IS-95. However, in 1X RTT, the reverse link transmits more than one code channel to accommodate the high data rates. The minimum configuration consists of a reverse pilot (R-Pilot) channel for synchronous detection by the base transceiver stations (BTS) and a reverse fundamental channel (R-FCH) for voice. Additional
channels such as the reverse supplemental channels (R-SCHs) and the reverse dedicated channel (R-DCCH) are used to send data or signaling information. Channels can exist at different rates and power levels. Table 1 shows the transmitter specification in CDMA2000 reverse link.
Specification
ERP at Maximum Output Power Minimum Controlled Output Power Waveform Quality Factor and Frequency Accuracy Spurious Emission at Maximum RF output power offset frequency within the range SR1, Band Class 0(Cellular band) 885 kHz to 1.98 MHz Less stringent of -42 dBc / 30 kHz or -54 dBm / 1.23 MHz 1.98 MHz to 3.125 MHz Less stringent of -54 dBc / 30 kHz or -54 dBm / 1.23 MHz 3.125 MHz to 5.625 MHz -13 dBm / 100 kHz Table 1. Transmitter Specification in Reverse Link.
Spread Rate1
Typical channel configurations below are based on the transmitter test condition in the reverse link. 1) "Basic" Voice only configuration - R-PICH @ -5.3 dB - R-FCH @ -1.5 dB 9.6 kbps 2) Voice and Data configuration - R-PICH @ -5.3 dB - R-FCH @ -4.54 dB 9.6 kbps - R-SCH1 @ -4.54 dB 9.6 kbps 3) Voice and Control configuration - R-PICH @ -5.3 dB - R-FCH @ -3.85 dB 9.6 kbps - R-DCCH @ -3.85 dB 9.6 kbps 4) Control channel only configuration - R-PICH @ -5.3 dB - R-DCCH @ -1.5 dB 9.6 kbps
Combinations of these channels will increase the peak to average power ratio for higher data rates. The complementary cumulative distribution function (CCDF) measurement characterizes the peak to average power statistics of CDMA2000 reverse link. For Electrical Data
improved thermal stability for PA linearity to meet the minimum system specifications. Test results for the ACPM-7831 as tested under 4 cdma2000 channel configurations are shown in the table below.
Parameter
800 MHz CDMA
Units
Measured
Comments
40 8.5 Pout 28.5 dBm Pout 28.5 dBm Pout 28.5 dBm Pout 26.0 dBm Pout 28.5 dBm Pout 28.5 dBm Pout 28.5 dBm Pout 26.0 dBm
-59 -48 -45 -56 dBc / 30 kHz -59 -61 -60 -66
Typical Channel Configurations
(a) "Basic" Voice only configuration · R-PICH @ -5.3 dB · R-FCH @ -1.5 dB 9.6 kbps (b) Voice and Data configuration · R-PICH @ -5.3 dB · R-FCH @ -4.54 dB 9.6 kbps · R-SCH1 @ -4.54 dB 9.6 kbps (c) Voice and Control configuration · R-PICH @ -5.3 dB · R-FCH @ -3.85 dB 9.6 kbps · R-DCCH @ -3.85 dB 9.6 kbps (d) Control channel only configuration · R-PICH @ -5.3 dB · R-DCCH @ -1.5 dB 9.6 kbps
Definitions: R-PICH Reverse Pilot Channel R-FCH Reverse fundamental channel R-SCH Reverse supplemental channel R-DCCH Reverse dedicated control channel
Basic
Voice + Data
Voice + CNTL
CNTL only
Design Tips to use Vcntl pin
Power Amplifier Control Using Vcntl Pin on ACPM-7812 Power amplifier control scheme in CDMA systems is one of the important and challenging aspects of CDMA-based handset design. Handset designers must balance maintaining adequate linearity while optimizing efficiency at high, medium and low output power levels. The primary method to achieve these goals is to adjust the bias of the PA as a function of output power. Theoretically, the best efficiency would be achieved when the bias of the PA is continually adjusted based on the output power
requirement of the PA. However, implementing this type of circuit is complex and costly. Therefore several different approaches have been developed to provide an acceptable trade-off between optimum efficiency and optimum manufacturability. The following section reviews four methods of controlling the bias of a CDMA power amplifier: fixed, step, logical and dynamic.
1. Fixed Bias Control
Power Mode Shut Down High Power
Vcntl 0V 2.5V
Power Range - 28.5 dBm
Note: Vcntl for Cell Band
Battery
Vdd2 Vdd1 PA Vcntl
To Duplexer
Baseband IC
Switch Circut for PA
2. Step Bias Control
Power Mode Shut Down Low Power Mid Power High Power
Vcntl 0V 1.2V 1.6V 2.5V
Power Range - ~ -5 dBm -5 dBm ~ 13 dBm 13 dBm ~ 28.5 dBm
Note: Adjust PDM1 pulse waveform to set low / mid / high power mode
Battery
Vdd2 Vdd1 PA Vcntl
To Duplexer
Enable Switch Circut for PA
Baseband IC
3. Logical Bias Control
Power Mode Shut Down Low Power Mid Power High Power
Vcntl 0V 1.2V 1.6V 2.5V
Power Range - ~ -5 dBm -5 dBm ~ 13 dBm 13 dBm ~ 28.5 dBm
Battery Switch Circuit for PA Enable To Duplexer
Vdd2 Vdd1 Vcntl
PA-ON
Pull-up Resistors Switch Circuit
Baseband IC
PA-R0 PA-R1
4. Dynamic Bias Control
Battery
To Duplexer
Vdd2 Vdd1 Vcntl
Vcontrol
Baseband IC
Enable Switch Circuit
R1 R2 Vin C1
Battery
To Duplexer
Vdd2 Vdd1 Vcntl
Vcontrol
Baseband IC
Enable Switch Circuit
ACPR Measurement Method Adjacent-channel power ratio (ACPR) is used to characterize the distortion of power amplifiers and other subsystems for their tendency to cause interference with neighboring radio channels or systems. The ACPR measurement often is specified as the
Offset frequency
Figure 18. CDMA Adjacent-Channel Power Ratio Measurement.
Offset Frequencies 1st ACPR 2nd ACPR
Cellular Band PCS Band 885 kHz 1.25 MHz 1.98 MHz 1.98 MHz
ACPR Testing Diagram Test
PA Test Setup
DC Power Supply CH1 CH2 CH3 8593E Spectrum Analyzer
Vcntl
Power Divider E4406A VSA Transmitter Tester
20 dB Attenuator
CDMA PA ACPM7812 / 7831
3 dB Attenuator
E4437B CDMA Signal Generator
Figure 19. ACPR PA test equipment setup.
ACPM-7812 Test Result using VSA Transmitter Tester
Figure 20. ACPR measurement using VSA Transmitter tester.
ACPR Test Results using Spectrum Analyzer
REF 42.8 dBm AT 30 dB Mkr 836 MHz 35.42 dBm
Center 836 MHz
VBW 100 kHz
Span 5.000 MHz SWP 2.00 sec
Figure 21. Example ACPR measurement using Spectrum Analyzer.
The meaning of 16 dB The accurate ACPR measurement using Spectrum Analyzer needs to consider the normalization factor that is dependent on the Resolution Bandwidth, RBW, settings. The above figure (measurement shown at 836 MHz for general example) shows a comparison of the different ACPR measurement results as a function of various RBW values. As the RBW is reduced, less power is captured during the measurement and consequently the
Since the ACPR in an IS95 system is specified in a 1.23 MHz bandwidth, a channel power that is measured using a different RBW, can be normalized to reflect the channel power as if it was measured in a 1.23 MHz bandwidth. The difference in channel power measured in 30 kHz bandwidth and the channel power measured in a 1.23 MHz bandwidth is 16 dB.
ACPR Test Results with Agilent ACPM-7812 CDMA PA
ACPM-7812
ACPR2 (dBc)
-30°C +25°C +60°C
ACPR1 (dBc)
-55 -60 -65 -70 -75 -80 0 5 10 15 Pout (dBm) 20
-30°C +25°C +60°C
15 Pout (dBm)
1st ACPR Measurement
2nd ACPR Measurement
ACPM-7812 Demoboard Operation Instructions
1) Module Description
5) Testing
2) Circuit Operation
configuration table. The Vdd sense connections are provided to allow the use of remotesensing power supplies for compensation for PCB traces and cable resistance. - Device Operation 1) Connect RF Input and Output for the band under test. 2) Terminate all unused RF ports into 50 Ohms. 3) Connect Vdd1 and Vdd2 supplies (including remote sensing labeled Vdd1 S and Vdd2 S on the board). Nominal voltage is 3.4V. 4) Apply RF input power according to the values listed in "Operation Data" in Data Packet. 5) Connect Vref (Vcntl) supply and set reference voltage to the voltage shown in the data packet. Note that the Vref (Vcntl) pin is on the back side of the demonstration board. Please limit Vref (Vcntl) to not exceed the corresponding listed "DC Biasing Condition" in the Data Packet. Note that increasing Vref (Vcntl) over the corresponding listed "DC Biasing Condition" can result in power decrease and current can exceed the rated limit.
The design of the power module (PAM) provide bias control via Vref (Vcntl) to achieve optimal RF performance and power control. The control pin is labeled Vref (Vcntl). Please refer to Figure 3 for the block diagram of this PAM.
Frequency Range Output Power Vcntl (Vref)
ACPM-7812
824 - 849 MHz 28.5 dBm 2.5 V
3) Maximum Ratings
Vdd Drain Current Vref (Vcntl) RF input Temperature 5.0V 1.5A 3V 10 dBm -30 to 80°C
Power Module Block Diagram
Vdd1 Vdd2
Power Input Match
The demonstration PC Board provides an adequate heat sink. Maximum device dissipation should be kept below 2.5 Watts.
Input
On Chip Inter-stage Match
Passive Output Match
Output
Vcntl (Vref)
ACPM-7812 Evaluation Board Schematic and Layout
Vdd1 C1 C5 Vdd1
RF Out
Vdd2 C3 Vdd2 C2
Vcntl C4 Vcntl
Layer 1 - Top Metal & Solder Mask (800MHz)
800 MHz
RF OUT
PIN Configuration Table
Top side
1 2 3 4 5 Ground Ground Vdd1 Ground Vdd2
Back side
1b Vdd2 Sense 2b Ground 3b Vdd1 Sense 4b Vref (Vcntl) 5b Ground
Layer 2 - Ground
Layer 3 - Bottom Metal & Solder Mask
S 1ddV
S 2ddV
IR Reflow Soldering Figure 22 is a straight-line representation of the recommended nominal time-temperature profile from JESD22-A113-B IR reflow.
235 200 183 150 60 to 150s above 183°C
TEMPERATURE (°C)
30 Preheat Zone
90 Soak Zone
150 180 TIME (seconds) Reflow Zone
270 Cooling Zone
Figure 22. Time-temperature Profile for IR Reflow Soldering Process.
Process Zone
Preheat Zone Soak Zone Reflow Zone Cooling Zone
Temperature
25°C to 100°C 100°C to 150°C 150°C to 235°C (240°C MAX) 235°C to 150°C 150°C to 25°C
Temperature / Time
3°C / s MAX 0.5°C / s MAX (120s MAX) 4.5°C / s TYP -4.5°C / s TYP -6°C / s MAX
Table1. IR Reflow Process Zone.
Convection or IR / Convection
Zone 1 - Preheat Zone The average heat up rate for surface-mount component on PCB shall be less than 3° C / second to allow even heating for both the component and PCB. This ramp is maintained until it reaches 100° C where flux activation starts. Zone 2 - Soak Zone The flux is being activated here to prepare for even and smooth solder joint in subsequent zone. The temperature ramp is kept gradual to minimize thermal mismatch between solder, PC Board and components. Overramp rate here can cause solder splatter due to excessive oxidation of paste. Zone 3 - Reflow Zone The third process zone is the solder reflow zone. The temperature in this zone rises rapidly from 183° C to peak temperature of 235° C for the solder to trans-
Solder Paste The recommended solder paste is type Sn6337A or Sn60Pb40A of J-STD-006.
Stencil or Screen The solder paste may be deposited onto PCB by either screen printing, using a stencil or syringe dispensing. The recommended stencil thickness is in accordance to JESD22-B102-C.
Nominal stencil thickness
0.102 mm (0.004 in) 0.152 mm (0.006 in) 0.203 mm (0.008 in)
Component lead pitch
Lead pitch less than 0.508 mm (0.020 in) 0.508 mm to 0.635 mm (0.02 in to 0.025 in) Lead pitch greater than 0.635 mm (0.025 in)
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