RF9938
6
Typical Applications
• CDMA/TDMA/DCS1900 PCS Systems
• PHS 1500/ WLAN 2400 Systems
• General Purpose Upconverter
• BPSK Modulation
• Micro-Cell PCS Base Stations
• Portable Battery-Powered Equipment
PCS UPCONVERTER/BPSK MODULATOR
Product Description
The RF9938 is a complete upconverter designed for PCS
applications. The IC contains a double-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 resis-
tors to provide high IP
3
. 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 is designed as part of the RFMD PCS CDMA
Chip Set, consisting of a Transmit IF AGC Amp, this
Transmit Upconverter, a Receive LNA/Mixer, and a
Receive IF AGC Amp.
0.008
0.004
0.018
0.014
-A-
0.196
0.189
0.050
6
0.157
0.150
0.244
0.229
Dimensions in mm
0.068
0.053
8° MAX
0° MIN
0.034
0.016
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".
Optimum Technology Matching® Applied
Si BJT
Si Bi-CMOS
ü
GaAs HBT
SiGe HBT
Package Style: SOIC-8
GaAs MESFET
Si CMOS
Features
• Supports Dual Mode Operation
• +8dBm Output Intercept Point
• Single 3.6V Power Supply
• Internally Matched Inputs and Outputs
• Buffered Output
• Double-Balanced Mixer
IF+ 1
IF- 2
GND 3
LO+ 4
8 RF OUT
7 VCC
6 GND
5 LO-
Ordering Information
RF9938
RF9938 PCBA
PCS Upconverter/BPSK Modulator
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 A3 010720
6-61
MIXERS
RFMD [ RF MICRO DEVICES ]
