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

203211A • Skyworks Proprietary and Confidential Information • Products and Product Information are Subject to Change Without Notice. • May 28, 2014

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PRODUCT SUMMARY

SKY77585 Tx-Rx Quad-Band Front-End Module for

GSM/GPRS (824-915 MHz) (1710-1910 MHz)

w/ Four Linear TRx Switch Ports

Applications

• Quad-band cellular

handsets encompassing

- Class 4 GSM850/GSM900

- DCS1800/PCS1900

- Class 12 GPRS multi-slot

operation

- EDGE downlink

compatible

Features

• High efficiency

• Low transmit supply current

• 50 Ω matched input/output

• Tx–VCO-to-antenna and

antenna-to-Rx-SAW filter

RF interface

• RF switch affords high

linearity, low insertion loss,

and 0 V DC on Rx ports

• Small, low profile package

- 6 mm x 6 mm x 0.9 mm

- 28-pad configuration

Description

SKY77585 is a transmit and receive Front-End Module (FEM) with integrated power amplifier control

designed in a low profile, compact form factor for quad-band cellular handsets comprising

GSM850/GSM900 and DCS1800/PCS1900 operation. The SKY77585 offers a complete Transmit VCO-

to-Antenna and Antenna-to-Receive SAW filter solution. The FEM also supports Class 12 General

Packet Radio Service (GPRS) multi-slot operation and EDGE downlink.

The module consists of a GSM850/GSM900 PA block and a DCS1800/PCS1900 PA block, impedance-

matching circuitry for 50

Ω input and output impedances, Tx harmonics filtering, high linearity/low

insertion loss RF switch, and a Power Amplifier Control (PAC) block. One PA block supports the

GSM850/GSM900 bands and the other PA block supports the DCS1800/PCS1900 bands. Both PA

blocks share common power supply pads to distribute current. The output of each PA block and the

outputs to the four receive pads are connected to the antenna pad through an RF switch. Four

broadband interchangeable receive ports provide flexibility to support multimode and multiband

configurations. The GaAs die, the CMOS die, the Switch die, and passive components are mounted on

a multi-layer laminate substrate. The assembly is encapsulated with plastic overmold.

Band selection and control of transmit and receive are performed using four external control pads.

Refer to the block diagram in Figure 1 below. The band select pad, BS1, BS2, Mode, and TxEN select

GSM850, GSM900, DCS, and PCS modes of operation.

Transmit enable TxEN controls receive or transmit mode of the RF switch (Tx = logic 1). Proper timing

between transmit enable TxEN and Analog Power Control VRAMP allows for high isolation between the

antenna and Tx–VCO while the VCO is being tuned prior to the transmit burst.

The SKY77585 is compatible with logic levels from 1.2 V to 2.9 V for BS1, BS2, MODE, and TxEN

pads.