I would appreciate any help or guide lines with the below
We have designed in the TPS54060 for a PSU, that seems to be working OK. Very near the PCB we have microphones that pick up acoustic noise around 8-10kHz that I need to remove
- Noise is from the main switching inductor (as far as I can tell)
- Due to major space constraints I cannot increase the switching inductor size.
- The switcher is currently operating around 130kHz (WEBENCH says it should be 220kHz?)
I have tried the following to try fix the Noise
- The original Inductor used was 47uH, but we have found a 22uH (sealed and shielded) that reduced the noise a little
- Changed the Compensation values
- Tried to change the switching frequency, but could not increase it for some reason (by lowering RT). I may be on some threshold?
- Removed all other circuit components other than the PSU, and used a restive load
(Circuit typical values Vin 50V, Vout 3V8, Iout 0.3- 0.4A)
