SKY77552中文资料Quad-Band Tx / Dual-Band Rx iPAC™ FEM for GSM / GPRS (824–915 MHz and 1710–1910 MHz)数据手册Skyworks规格书

描述 Description

The SKY77552 is a quad-band transmit and dual-band receive front-end module (FEM) withIntegrated Power Amplifier Control (iPAC™) for cellular handsets comprising GSM and DCS/PCSoperation. The FEM has quad-band capability in applications of U.S. or Euro dual-band platforms.Designed in a low profile, compact form factor, the SKY77552 offers a complete Transmit VCO-to-Antenna and Antenna-to-Receive SAW filter solution. The FEM also supports Class 12 General PacketRadio Service (GPRS) multi-slot operation.

The module consists of a GSM PA block and a DCS/PCS PA block, impedance-matching circuitry for50 Ω input and output impedances, Tx harmonics filtering, high linearity and low insertion lossPHEMT RF switches, diplexer and a Power Amplifier Control (PAC) block with internal current senseresistor. A custom BiCMOS integrated circuit provides the internal PAC function and decoder circuitryto control the RF switches. The two Heterojunction Bipolar Transistor (HBT) PA blocks are fabricatedonto a single Gallium Arsenide (GaAs) die. One PA block supports the GSM band and the other PAblock supports the DCS/PCS band. Both PA blocks share common power supply pads to distributecurrent. The output of each PA block and the outputs to the two receive pads are connected to theantenna pad through PHEMT RF switches and a diplexer. The GaAs die, PHEMT die, Silicon (Si) dieand passive components are mounted on a multi-layer laminate substrate. The assembly isencapsulated with plastic overmold.

Band selection and control of transmit and receive modes are performed using two external controlpads. Refer to the functional block diagram in Figure 1. The band select pad (BS) selects betweenGSM and DCS/PCS modes of operation. The transmit enable (TxEN) pad controls receive or transmitmode of the respective RF switch (Tx = logic 1). Proper timing between transmit enable (TxEN) andAnalog Power Control (VRAMP) allows for high isolation between the antenna and Tx-VCO while theVCO is being tuned prior to the transmit burst.

The SKY77552 is compatible with logic levels from 1.2 V to VCC for BS and TxEN pads, depending onthe level applied to the VLOGIC pad. This feature provides additional flexibility for the designer in theselection of FEM interface control logic.

特性 Features

• High efficiency- 43.5% GSM- 37.5% DCS/PCS
• Low transmit supply current- 1.31 A GSM- 0.96 A DCS/PCS
• Internal ICC sense resistor for iPAC
• Closed loop iPAC
• 50 Ω matched Input/Output
• Tx–VCO-to-antenna and antenna-to-Rx-SAW filter RF interface
• PHEMT RF switches afford high linearity, low insertion loss, and less than 20 μA supply current in receive modes
• Small, low profile package: 7 x mm 6 mm x 0.9 mm
• Compatible with multiple logic families
• Low VRAMP current: 25 μA

应用 Application

• Smartphones