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RF9908 Datasheet, PDF (1/4 Pages) RF Micro Devices – CDMA/FM UPCONVERTER/BPSK MODULATOR
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Typical Applications
• CDMA/FM Cellular Systems
• Supports Dual-Mode AMPS/CDMA
• Supports Dual-Mode TACS/CDMA
RF9908
CDMA/FM UPCONVERTER/BPSK MODULATOR
• Commercial and Consumer Systems
• 3-Cell Battery-Operated Systems
Product Description
The RF9908 is a complete upconverter designed for
CDMA/FM cellular applications. The IC contains a dou-
ble-balanced mixer stage and an output buffer amplifier
stage. This device may also be used to directly BPSK
modulate a carrier. The mixer is a Gilbert cell with emitter
degeneration resistors to provide high IP3. The output
stage is a class-B, push-pull configuration to reduce the
overall current and still provide a good 50Ω output match.
The unit operates at 3.6V and does not require any exter-
nal matching components other than coupling capacitors.
This circuit is designed as part of the RFMD CDMA Chip
Set, consisting of a Transmit IF AGC Amp, this Transmit
Upconverter, a Receive LNA/Mixer, and a Receive IF
AGC Amp.
0.196
0.189
8° MAX
0° MIN
0.157
0.150
0.244
0.229
0.034
0.016
0.018
0.014
-A-
0.008
0.004
0.050
Dimensions in mm
0.068
0.053
0.009
0.007
NOTES:
1. Shaded lead is Pin 1.
2. All dimensions are excluding
mold flash.
3. Lead coplanarity -
0.005 with respect to datum "A".
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Optimum Technology Matching® Applied
Si BJT
üGaAs HBT
GaAs MESFET
Si Bi-CMOS
SiGe HBT
Si CMOS
IF+ 1
IF- 2
GND 3
LO+ 4
8 RF OUT
7 VCC
6 GND
5 LO-
Package Style: SOIC-8
Features
• Supports Dual Mode Operation
• +8dBm Input/Output Intercept Point
• Single 3.6V Power Supply
• Internally Matched Inputs and Outputs
• Buffered Output
• Double-Balanced Mixer
Ordering Information
RF9908
CDMA/FM Upconverter/BPSK Modulator
RF9908 PCBA Fully Assembled Evaluation Board
Functional Block Diagram
RF Micro Devices, Inc.
7628 Thorndike Road
Greensboro, NC 27409, USA
Tel (336) 664 1233
Fax (336) 664 0454
http://www.rfmd.com
Rev A2 010720
6-57