General Description

The MAX9989 and MAX9990 LO buffers provide the high output (+14dBm to +20dBm) necessary to drive the LO inputs of high-linearity passive mixers, while offering 40dB reverse isolation to prevent LO pulling. The MAX9989 is internally matched for the cellular/GSM bands, and the MAX9990 is matched for the DCS/PCS/UMTS bands.

Features

♦ ±1dB Output Power Variation

♦ +14dBm to +20dBm Adjustable Output Power

♦ 40dB Reverse Isolation

♦ Better Than 35dB Main Driver Output to PLL Amp Output Isolation

♦ Low Output Noise: -170dBc/Hz at +17dBm

♦ 110mA Supply Current at +17dBm

♦ ESD Protection

♦ Isolated PLL Output (+3dBm)

Applications

    Cellular/GSM/DCS/PCS/UMTS Base Station Tx/Rx LO Drives

    Coherent Receivers

    ISM Wireless LAN

    Wireless Local Loop

    Local Multipoint Distribution Service

    Point-to-Point Systems