
Skyworks Solutions, Inc. Phone [781] 376-3000 Fax [781] 376-3100 sales@skyworksinc.com www.skyworksinc.com
1017887C Skyworks Proprietary and Confidential Information Products and Product Information are Subject to Change Without Notice. January 6, 2006
1
DATA SHEET
CX77105 Power Amplifier Module for CDMA/AMPS
(824–849 MHz)
Applications
Digital cellular (CDMA)
Analog cellular (AMPS)
Wireless local loop (WLL)
Features
Low voltage positive bias
supply
- 3.2 V to 4.2 V, typical
Good linearity
High efficiency
Dual mode operation
Large dynamic range
10-pad package
- 4 x 4 x 1.5 mm
Power down control
Low power-state control
InGaP
IS 95/CDMA2000
Skyworks offers lead
(Pb)-free "environmentally
friendly" packaging
that is RoHS compliant
(European Parliament
for the Restriction of
Hazardous Substances).
Description
The CX77105, a dual-mode, Code Division Multiple Access (CDMA) / Advanced Mobile Phone Service
(AMPS) Power Amplifier Module (PAM), is a fully matched, 10-pad surface mount module developed
for cellular handsets and wireless local loop applications. This small and efficient power amplifier
module packs a full 824–849 MHz bandwidth coverage into a single compact package. The device
meets the stringent IS95 CDMA linearity requirements to and exceeding 28 dBm output power, and
can be driven to levels beyond 31 dBm for high efficiency in FM mode operation. A low current digital
pad (VCONT) provides improved efficiency for the low RF power range of operation.
The single Gallium Arsenide (GaAs) Microwave Monolithic Integrated Circuit (MMIC) contains all active
circuitry in the module. The MMIC contains on-board bias circuitry, as well as input and interstage
matching circuits. Output match into a 50
load is realized off-chip and within the module package
to optimize efficiency and power performance. This device is manufactured with Skyworks’ GaAs
Heterojunction Bipolar Transistor (HBT) process that provides for all positive voltage DC supply
operation while maintaining high efficiency and good linearity. Primary bias to the CX77105 is
supplied directly from a three-cell Ni-Cd, a single-cell Li-Ion, or other suitable battery with an output
in the 3 to 4 volt range. Power down is accomplished by setting the voltage on the low current
reference pad to zero volts. No external supply side switch is needed as typical “off” leakage is a few
microamperes with full primary voltage supplied from the battery.
RF_IN (4)
(8) RF_OUT
VCC1 (5)
GND
(3, 7, 9, 10)
VREF (1)
Driver
Stage Bias
Power
Stage Bias
Input
Match
DA
Inter-Stage
Match
PA
Output
Match
VCC2 (6)
VCONT (2)
101787_001
MMIC
MODULE
Figure 1. CX77105 Functional Block Diagram