Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • sales@skyworksinc.com • www.skyworksinc.com

103030B • Skyworks Proprietary and Confidential information. • Products and product information are subject to change without notice. • September 9, 2005

1

DATA SHEET

SKY77321 PA Module for Tri-Band EGSM / GPRS

Applications

• Tri-band cellular handsets

encompassing

-

Class 4 EGSM900

-

Class 1 DCS1800

-

PCS1900

-

GPRS (up to Class 12)

Features

• High efficiency

-

EGSM900 53%

-

DCS1800 47%

PCS1900 47%

• Input/output matching

50

Ω internal

• Small outline

6 mm x 6 mm

• Low profile

1.2 mm maximum

• Low APC current

10 µA typical

• Gold plated, lead-free

contacts

Skyworks offers lead

(Pb)-free "environmentally

friendly" packaging

that is RoHS compliant

(European Parliament

for the Restriction of

Hazardous Substances).

Description

The SKY77321 Power Amplifier Module (PAM) is designed in a compact form factor for tri-band

cellular handsets comprising EGSM900, DCS1800, and PCS1900 operation. It also supports Class 12

General Packet Radio Service (GPRS) multislot operation.

The PAM consists of an EGSM900 PA block, a DCS1800/PCS1900 PA block, impedance-matching

circuitry for 50

Ω input and output, and bias control circuitry. Two separate Heterojunction Bipolar

Transistor (HBT) PA blocks are fabricated on a single Gallium Arsenide (GaAs) die. One PA block

operates in the EGSM900 band and the other PA block supports both the DCS1800 and the PCS1900

bands. Optimized for Li-Ion battery operation, both PA blocks share common power supply pins to

distribute current. A custom CMOS integrated circuit provides the internal interface circuitry, including

die, the Silicon (Si) die, and passive comments are mounted on a multi-layer laminate substrate. The

assembly is encapsulated with plastic overmold.

The RF input and output ports are internally matched to 50

Ω to reduce the number of external

components for a tri-band design. Extremely low leakage current (2 µA, typical) of the dual PA module

maximizes handset standby time. The SKY77321 also contains band-select switching circuitry to

select EGSM (logic 0) and DCS/PCS (logic 1) as determined from the Band Select (BS) signal. In the

block diagram shown below, the BS pin selects the PA output (DCS/PCS OUT or EGSM OUT) while the

Analog Power Control (APC) controls the level of output power.

Figure 1. Functional Block Diagram