Avago 公司的ALM-1712是 GPS 低噪音放大器前端模块,它把低噪音放大器(LNA)和GPS FBAR滤波器组合在一起. ALM-1712采用先进的GaAs E-pHEMT和FBAR技术,具有非常低的噪音,典型值为1.65dB,关断电六小于1uA,RF输入引脚的ESD大于3KV,电源电压可低到1.0V,并能通过单一外接电阻调整偏压电流.本文介绍了ALM-1712的主要特性, 演示板和应用电路框图, 演示板元件布局图和所用元件表以及S参数和测量参考平面.

    ALM-1712: GPS Low-Noise Amplifier Front-end Module with Integrated Pre and Post Filters and Variable Current/Shutdown Function

    Avago Technologies’ ALM-1712 is a GPS front-end module that combines a low-noise amplifier (LNA) with GPS FBAR filters. The LNA uses Avago Technologies’ proprietary GaAs Enhancement-mode pHEMT process to achieve high gain with very low noise figure and high linearity. Noise figure distribution is very tightly controlled. A CMOS-compatible shutdown pin is included either for turning the LNA on/off, or for current adjustment. The integrated filter utilizes an Avago Technologies’ leading-edge FBAR filter for exceptional rejection at Cell/PCS-Band frequencies.

    The low noise figure and high gain, coupled with low current consumption make it suitable for use in critical low-power GPS applications or during low-battery situations.

    ALM-1712主要特性:

    Very Low Noise Figure : 1.65 dB typ

    Exceptional Cell/PCS-Band rejection

    Advanced GaAs E-pHEMT & FBAR Technology

    Low external component count

    Shutdown current : < 1 uA

    CMOS compatible shutdown pin (SD)

    ESD : >3kV at RFin pin

    1mm typical thickness

    Adjustable bias current via single external resistor/voltage

    Useable down to 1.0V supply voltage

    Small package dimension: 4.5(L)x2.2(W)x1(H) mm3

    Meets MSL3, Lead-free and halogen free

    Specifications (Typical performance @ 25°C)

    At 1.575GHz, Vdd = 2.7V, Idd = 8.0mA

    Gain = 12.8 dB

    NF = 1.65 dB

    IIP3 = +7 dBm, IP1dB = +3 dBm

    S11 = -9 dB, S22 =-10 dB

    Cell-Band Rejection: 95dBc

    PCS-Band Rejection: 90dBc

    ALM-1712应用:

    GPS Front-end Module

    图1.ALM-1712应用电路

    图2.ALM-1712演示板和应用电路框图

    图3. ALM-1712演示板元件布局图

    表1.演示板和应用电路元件表

    图4.ALM-1712 S参数和测量参考平面