• State TI Thinks Resolved
  • Locked Locked
  • Replies 5 replies
  • Answers 1 answer
  • Subscribers 62 subscribers
  • Views 251 views
  • Users 0 members are here
Support feedback
Options
Options
Related

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.

LM5176: LM5176 Humming Noise on Inductor

saravanan krishnan
Prodigy 70 points

Part Number: LM5176

Tool/software:

HI team ,

Issue Summary – LM5176-Q1 Buck-Boost Humming Near VIN ≈ VOUT

We are using LM5176-Q1 in a 4-switch buck-boost design, generating 28 V output from a 10–30 V input range.,Vout is set for 28V.

  • V1.0 board: Works fine across the full range, clean SW node, no audible issues.

  • V1.1 board: Same schematic,additional some components placed for EMI/EMC Complaince.

  • Symptom: At VIN = 23–30 V (≈ VOUT), SW node shows burst/noisy behavior (~180 kHz packets) and audible hum. Below 23 V (boost mode)  operation is clean.

    The issue occurs with no load and with load(Tested with 1.6A). Request your support/analysis to debug the issue .I have attached schematics V1.1 & V1.0 along with waveform capture.LM5176_Buck_Boost_Humming_Noise_Texas_Insturments_V0.1.pdf