CX77312

ADVANCE PRODUCT SUMMARY SUMMARY CX77312: iPAC™ PAM for Quad-Band GSM / GPRS APPLICATIONS Quad-band cellular handsets encompassing - Class 4 GSM850/900 - Class 1 DCS1800 PCS1900 - Class 12 GPRS multi-slot operation The CX77312 Power Amplifier Module (PAM) is designed in a compact form factor for quad-band cellular handsets comprising GSM850/900, DCS1800, and PCS1900 operation. The PAM also supports Class 12 General Packet Radio Service (GPRS) multi-slot operation. The module consists of separate GSM850/900 PA and DCS1800/PCS1900 PA blocks, impedance-matching circuitry for 50 W input and output impedances, and a Power Amplifier Control (PAC) block with an internal current-sense resistor. The custom CMOS integrated circuit provides the internal PAC function and interface circuitry. Fabricated onto a single Gallium Arsenide (GaAs) die, one Heterojunction Bipolar Transistor (HBT) PA block supports the GSM850/900 bands and the other supports the DCS1800 and PCS1900 bands. Both PA blocks share common power supply pins to distribute current. The GaAs die, the Silicon (Si) die, and the passive components are mounted on a multi-layer laminate substrate. The assembly is encapsulated with plastic overmold. RF input and output ports of the CX77312 are internally matched to 50 Ω to reduce the number of external components for a quad-band design. Extremely low leakage current (2.5 mA, typical) of the dual PA module maximizes handset standby time. The CX77312 also contains band-select s...