SLVAFJ0 april   2023 TPS650350-Q1

 

  1.   Passing CISPR-25 Radiated and Conduction Emissions Using the TPS65035x-Q1
  2.   Trademarks
  3. 1Introduction
  4. 2Spread Spectrum
  5. 3Schematics and Printed Circuit Board (PCB) Description
    1. 3.1 Schematics
    2. 3.2 Bill of Materials
    3. 3.3 Board Layout
  6. 4Design Considerations
  7. 5Summary
  8. 6Conducted and Radiated Emission Average and Peak Plots
  9. 7References

Schematics and Printed Circuit Board (PCB) Description

This layout is derived from a compact camera module reference design. All non-power related components have been removed from the original design, and the remaining power solution was tested according to the CISPR-25 automotive specification. A power over coax (POC) filter is included on both ends of the harness (FPD-Link coax cable) to replicate the expected EMI in a typical automotive camera application. The schematic and layout for the POC filter on the receiver side are taken from the Automotive Camera PMIC Power Supply Reference Design with Power Over Coax Filter reference design. The schematic and layout for the POC filter on the DUT-side is shown in Figure 3-2. As intended for a camera module reference design, the layout balances the tradeoffs between PCB area and EMI performance. For example, some components for the low-voltage buck converters are located on the layer opposite of the PMIC to minimize the total area occupied by the power solution. These are less critical for EMI performance compared to the mid-voltage buck converter.

GUID-E72100E3-0983-479D-8C1C-EE8419EA6A4E-low.pngFigure 3-1 CISPR-25 EMC Test Setup