SKY77331

www.DataSheet4U.com PRELIMINARY PRODUCT SUMMARY SKY77331 Power Amplifier Module with Integrated Coupler for Quad-Band GSM / EDGE Applications Quad-band cellular handsets: - Class 4 GSM850/900 - DCS1800 - PCS1900 - Class 12 GPRS multi-slot operation - EDGE polar modulation Description The SKY77331 Power Amplifier Module (PAM) is designed in a compact form factor for quad-band cellular handsets comprising GSM850/900, DCS1800, PCS1900, and supports Class 12 General Packet Radio Service (GPRS) multi-slot operation. The module consists of a GSM850/900 PA block and a DCS1800/PCS1900 PA block, impedancematching circuitry for 50 Ω input and output impedances, a Power Amplifier Control (PAC) block, and an Integrated Coupler. A custom CMOS IC provides the internal PAC function and interface circuitry. Two separate Heterojunction Bipolar Transistor (HBT) PA blocks are fabricated onto InGaP/GaAs die; one supports the GSM850/900 bands, the other supports the DCS1800 and PCS1900 bands. Both PA blocks share common power supply pads to distribute current. The GaAs die, the silicon die, and the passive components are mounted on a multi-layer laminate substrate with the entire assembly encapsulated with plastic overmold. RF input and output ports are internally matched to 50 Ω to reduce the number of external components for a quad-band design. Extremely low leakage current (10 µA, maximum) of the dual PA module maximizes handset standby time. The SKY77331 also contains band select switchi...