Top

+14dBm to +20dBm LO Buffers with ±1dB Variation

Product Details

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.

The Typical Application Circuit provides a nominal +17dBm output power with ±1dB variation over supply, temperature, and input power. With two optional resistors, the output power can be precision set from +14dBm to +20dBm. The devices offer more than 35dB main driver output to PLL amp output isolation. Each device is offered in a 5mm x 5mm 20-pin thin QFN package with exposed paddle.

Key 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/Uses

    • Cellular/GSM/DCS/PCS/UMTS Base Station Tx/Rx LO Drive
    • Coherent Receivers
    • ISM Wireless LAN
    • Local Multipoint Distribution Service
    • Point-to-Point Systems
    • Wireless Local Loop (WLL)
    Parametric specs for VCO Buffers/Splitters
    LO Driver Outputs Yes
    PLL Driver Outputs Yes
    RF Freq. (MHz) (min) 700
    RF Freq. (MHz) (max) 1100
    POUT (dBm) (min) 14.3
    POUT (dBm) (max) 19.7
    VCC (V) 4.75 to 5.25
    ISUPPLY (mA) 105
    Footprint (mm x mm) 5.0 x 5.0
    Package/Pins TQFN/20
    View More

    Simplified Block Diagram

    MAX9989, MAX9990: Typical Operating Circuit MAX9989, MAX9990: Typical Operating Circuit Zoom icon

    Technical Docs

    Design & Development

    Click any title below to view the detail page where available.

    /en/design/design-tools/ee-sim.html?

    Support & Training

    Search our knowledge base for answers to your technical questions.

    Filtered Search

    Our dedicated team of Applications Engineers are also available to answer your technical questions. Visit our support portal

    Parameters

    Parametric specs for VCO Buffers/Splitters
    LO Driver Outputs Yes
    PLL Driver Outputs Yes
    RF Freq. (MHz) (min) 700
    RF Freq. (MHz) (max) 1100
    POUT (dBm) (min) 14.3
    POUT (dBm) (max) 19.7
    VCC (V) 4.75 to 5.25
    ISUPPLY (mA) 105
    Footprint (mm x mm) 5.0 x 5.0
    Package/Pins TQFN/20

    Key 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/Uses

    • Cellular/GSM/DCS/PCS/UMTS Base Station Tx/Rx LO Drive
    • Coherent Receivers
    • ISM Wireless LAN
    • Local Multipoint Distribution Service
    • Point-to-Point Systems
    • Wireless Local Loop (WLL)

    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.

    The Typical Application Circuit provides a nominal +17dBm output power with ±1dB variation over supply, temperature, and input power. With two optional resistors, the output power can be precision set from +14dBm to +20dBm. The devices offer more than 35dB main driver output to PLL amp output isolation. Each device is offered in a 5mm x 5mm 20-pin thin QFN package with exposed paddle.

    Simplified Block Diagram

    MAX9989, MAX9990: Typical Operating Circuit MAX9989, MAX9990: Typical Operating Circuit Zoom icon

    Technical Docs

    Support & Training

    Search our knowledge base for answers to your technical questions.

    Filtered Search

    Our dedicated team of Applications Engineers are also available to answer your technical questions. Visit our support portal