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

3.3 High-Side Switch

The high-side switch is placed between the boost converter and the LED driver and buffer capacitor. The high-side switch limits the output current of the boost converter and thus also the PoC current on the input side. This makes sure that the current rating of the components on the PoC side is not exceeded.

The procedure to determine the minimum current limit for a given LED configuration is described in the Design Steps section.

The design uses the TPS1H000-Q1 high-side switch due to the adjustable current limit and small size.