SNWA014 November   2023 LMH2110

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Log Detector System
    1. 2.1 Block Diagram
    2. 2.2 Output Swing Derivation
    3. 2.3 Simulation Results
  6. 3Power Detector – LMH2110
    1. 3.1 Description
    2. 3.2 Log Conformance
    3. 3.3 Calibration
  7. 4Additional Approaches
    1. 4.1 External ADC Approach
    2. 4.2 Single-Ended Approach
  8. 5Summary
  9. 6References

Log Conformance

To describe how close the transfer is to a logarithmic function, the log conformance error is used. To calculate the log conformance error the detector transfer function is modeled as a linear-in-dB relationship between the input power and the output voltage. Section 8.2.1.2.1.2 of the LMH2110 8-GHz Logarithmic RMS Power Detector with 45-dB Dynamic Range data sheet explains how the log conformance error is calculated.

GUID-20230725-SS0I-5WSW-T06F-ZGGDXL3GZTMF-low.pngFigure 3-2 VOUT and Log Conformance Error of LMH2110 Across Dynamic Range at 1900 MHz