SNVAA88 December   2023 LM51581-Q1 , TPS1H000-Q1 , TPS92642-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2System Description
    1. 2.1 Dual Cable Concept
    2. 2.2 Single Cable Concept
  6. 3Camera Module Design with Single Coaxial Cable Connection
    1. 3.1 Power-Over-Coax Filter
    2. 3.2 Boost Converter
    3. 3.3 High-Side Switch
    4. 3.4 Buffer Capacitor
    5. 3.5 LED Driver
    6. 3.6 Serializer
    7. 3.7 Design Steps
  7. 4Test Results
    1. 4.1 LED and PoC Voltage Waveforms
    2. 4.2 Margin Analysis Program Result
    3. 4.3 Differential Supply Noise Level
    4. 4.4 Test Cases
  8. 5Summary
  9. 6References

Summary

The presented single cable implementation using Power-over-Coax helps reducing the amount of cabling needed for a DMS system with a remote camera module. The approach to combine the power connection for IR illumination with the PoC connection for the camera subsystem enables lowering cost and weight of the camera module cabling. The app note also discussed how the basic parameters can be calculated for a chosen LED string configuration. The presented test results proving that with the correct configuration the noise impact from the pulsing IR LEDs on the high-speed FPD-Link forward and back channel is within the specified limits.