Data Sheet

101787A

© 2001, 2002 Skyworks Solutions, Inc., All Rights Reserved.

December 10, 2002

CX77105

Power Amplifier Module for CDMA/AMPS (824–849 MHz)

The CX77105, a dual-mode, Code Division Multiple Access (CDMA) / Advanced

Mobile Phone Service (AMPS) Power Amplifier Module (PAM), is a fully matched,

10-pin 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 pin (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. The output match is realized off-chip

and within the module package to optimize efficiency and power performance into a

50

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 nickel cadmium, a single-cell lithium ion, or other

suitable battery with an output in the 3–4 volt range. Power down is accomplished by

setting the voltage on the low current reference pin 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.

Functional Block Diagram

MMIC

MODULE

RF IN (4)

(8) RF OUT

VCC1

(3, 7, 9, 10)

GND

(3, 7, 9, 10)

GND

VCC2

VREF

Driver

Driver

Stage Bias

Stage Bias

Power

Power

Stage Bias

Stage Bias

Input

Input

Match

Match

DA

DA

Inter

Inter

Stage

Stage

Match

Match

PA

PA

Output

Output

Match

Match

(1)

(5)

(6)

VCONT

(2)

Distinguishing 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-pin package (4 x 4 x 1.5 mm)

•

Power down control

•

Low power-state control

•InGaP

•

IS 95/CDMA2000

Applications

•

Digital cellular (CDMA)

•

Analog cellular (AMPS)

•

Wireless local loop (WLL)