SKY77523 Datasheet, PDF (1/2 Pages) Skyworks Solutions Inc. – Tx/Rx Front-End Module with Integrated Coupler for Quad-Band GSM and EDGE Applications

PRODUCT SUMMARY
SKY77523: Tx/Rx Front-End Module with Integrated Coupler
for Quad-Band GSM and EDGE Applications
Applications
• Quad-band, cellular handsets:
− Class 4 GSM850, EGSM900
− DCS1800
− PCS1900
− Class 12 EGPRS multi-slot operation
− Class 34 EGPRS multi-slot operation
− EDGE polar modulation
Features
• High efficiency:
− GSM850, 45% (peak)
− GSM900, 45% (peak)
− DCS1800, 38% (peak)
− PCS1900, 38% (peak)
• Integrated coupler
• Wideband envelope control path
• Input/output matching
• MCM (34-pin, 6 x 8 mm) Pb-free (MSL3, 250 °C per JEDEC J-
STD-020) package
Skyworks offers lead (Pb)-free, RoHS (Restriction of
Hazardous Substances) compliant packaging.
Description
The SKY77523 is a transmit/receive Front-End Module (FEM)
designed for Skyworks Helios™ II-Plus EDGE RF Subsystem. This
subsystem is intended for multi-band Global System for Mobile
Communications (GSM), General Packet Radio Service (GPRS),
and Enhanced Data Rate for GSM Evolution (EDGE) handsets and
modules. This subsystem supports GSM850, EGSM900,
DCS1800, and PCS1900 applications.
The SKY77523 provides a complete transmit Voltage-Controlled
Oscillator (VCO)-to-antenna and antenna-to-receive Surface
Acoustic Wave (SAW) filter solution.
The module consists of a single GSM850/EGSM900 and
DCS1800/PCS1900 PA block, a PA Control (PAC) block,
impedance-matching circuitry for 50 Ω inputs and outputs,
transmit harmonic filtering, an integrated coupler, high-linearity
and low insertion-loss pHEMT RF switches, and a diplexer. A
custom CMOS integrated circuit provides the internal PAC
function, interface circuitry, and decoder circuitry to control the
RF switches.
Two Heterojunction Bipolar Transistor (HBT) PA blocks are
fabricated onto an Indium Gallium Phosphide (InGaP) die; one
block supports the GSM850 and EGSM900 bands, the other
supports the DCS1800 and PCS1900 bands. Both PA blocks share
common power supply pads to distribute current. Outputs from
the PA blocks and the four receive pads connect to the antenna
using pHEMT RF switches and the diplexer. The InGaP die, the
Silicon (Si) die, the pHEMT die, and the passive components are
mounted on a multi-layer laminate substrate, and the entire
assembly encapsulated with plastic overmold.
Three external control pins facilitate band selection, and control of
the transmit and receive RF signal flows. Pin signals BS0 and BS1
select GSM, DCS, or PCS modes. The TR_EN pin signal selects
transmit or receive mode of the respective RF switch. Proper
timing of the pin signal logic and power control (the VPC pin)
allows high isolation between the antenna and the transmit VCO
while the VCO is being tuned before the transmit burst.
The PAC_EN signal enables the PAC circuitry to minimize battery
drain. The low leakage current (6.5 µA, typical) of the dual PA
module maximizes handset standby time.
The SKY77523, together with the SKY74138 RF transceiver, form
the Helios II-Plus EDGE RF Subsystem. Feedback signals from the
SKY77523 to the SKY74138 form an integral portion of the
Skyworks Polar Loop™ architecture. This architecture
autonomously splits amplitude and phase using the traditional
analog In-Phase and Quadrature (I/Q) signals. The filter-saving
advantage of the translation-loop approach is embedded in the
architecture. Also included is an AM loop that provides both signal
AM and power level control.
The SKY77523 is packaged in a small, 34-pin 6 x 8 mm Multi-
Chip Module (MCM) package. A functional block diagram is
shown in Figure 1.
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [e-mail] • www.skyworksinc.com
200612B • Skyworks Proprietary and Confidential information • Products and Product Information are Subject to Change Without Notice • December 7, 2006
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