• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 64 subscribers
  • Views 127 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TPSM846C24: High frequency noise

JH Shin
Guru 10400 points
Part Number: TPSM846C24

Hello,

My customer is using the TPSM846C24 with two-phase mode.

A high-frequency noise is generated from a board designed by the customer, and the customer suspects that it is coming from the TPSM846C24.

Please let us know if there is a way to accurately check whether high-frequency noise is occurring.

If it is true that it occurs in TPSM846C24, please tell us how to remove the high frequency noise.

Thank you.

JH

  • 0
    TI__Mastermind 32320 points

    Hello JH, 

    1. what is the frequency of the noise? that one way to check if it is coming from the TPS. check if the noise is related to switching frequency for the device.
    2. The other thing you can check the Switch node. can you probe the Switch node and see if there are lots ringing.
    3. High di/dt current loop and any inductance in its path, check VOUT

    Depends on what is the root cause of the noise, but typically

    • optimize (minimize) the area of the high di/dt loop.
    • The high di/dt loop is formed by the input capacitor and the power MOSFETs (switches). here are some steps you can take – put the Input capacitor as close as possible to IC (Smaller loop area) – make sure to have a Smaller loop area (Lower ringing on SW node)-- Lower ringing on SW node = Lower output noise

    I attached a good document that details sources of noise in buck converts and how to fix them. But you start taking any steps of fixing them, you need to make sure the issue you are referring to is really coming from  the TPSM546C24 

     https://www.ti.com/lit/ml/slyp709/slyp709.pdf?ts=1700233374281&ref_url=https%253A%252F%252Fwww.google.com%252F

    Thanks 

    Tahar