LMX2531 High Performance Frequency Synthesizer System with Integrated VCO | TI.com

LMX2531 (ACTIVE) High Performance Frequency Synthesizer System with Integrated VCO



The LMX2531 is a low-power, high-performance frequency synthesizer system which includes a fully integrated delta-sigma PLL and VCO with fully integrated tank circuit. The third and fourth poles are also integrated and adjustable. Ultra-low noise and high-precision LDOs are integrated for the PLL and VCO, which yield higher supply-noise immunity and more consistent performance. When combined with a high-quality reference oscillator, the LMX2531 device generates very stable, low-noise local-oscillator signals for up and down conversion in wireless communication devices. The LMX2531 device is a monolithic integrated circuit, fabricated in an advanced BiCMOS process. Several different versions of this product accommodate different frequency bands.


  • Multiple Frequency Options Available
    • See Device Information Table
    • Frequencies From: 553 MHz to 3132 MHz
  • PLL Features
    • Fractional-N Delta-Sigma Modulator Order
      Programmable up to Fourth Order
    • FastLock/Cycle Slip Reduction with Timeout
    • Partially Integrated, Adjustable Loop Filter
    • Very Low Phase Noise and Spurs
  • VCO Features
    • Integrated Tank Inductor
    • Low Phase Noise
  • Other Features
    • 2.8-V to 3.2-V Operation
    • Low Operating Current
    • Low Power-Down Current
    • 1.8-V MICROWIRE Support
    • 36-Pin 6-mm × 6-mm × 0.8-mm WQFN Package

Design with LMX2531

Recommend Input Frequency Tunable Output Frequency
Input Frequency Min Output Frequency
 MHz  MHz
Max Output Frequency
Channel Spacing


Compare all products in RF PLLs & synthesizers Email Download to Excel
Part number Order Output frequency (Min) (MHz) Output frequency (Max) (MHz) Normalized PLL phase noise (dBc/Hz) 1/f noise (10-kHz offset at 1-GHz carrier) (dBc/Hz) Current consumption (mA) VCC (V) Integrated VCO
LMX2531 Order now 553     3132     -212     -104     34     2.8 to 3.2     Yes