Hello,
at the moment I'm doing software development for a pimped version of Dave Ericksons PS-Load
http://djerickson.com/ps-load/.
During all the software and hardware testing I became more and more annoyed by the hissing sound of the isolated DC-DC converter on the board.
The sound is at a frequency of 12-13kHz (my Smartphone told me) and is horrible to listen at if you need to work next to it.
To improve this sound I already tried some things:
- Adding some capacitors (MLCC) at the inputs and outputs
- Packing the DC-DC in some packing foam (didn't help at all)
- Mirror my test setup. Now I sit left instead of right of the board as my right ear seems to be less sensitive to this frequency
To get finally rid of this hissing sound I ordered some other DC-DCs to try if I can find one that is also good and silent.
Sadly It seems like I couldn't find a part that works. All DC-DCs I bought seem to have this issue at the one or the other frequency.
Does anyone have a suggestion for a good DC-DC that can withstand my (maybe) too good ears?
The Specs the DC-DC needs to fulfill:
- Galvanically isolated
- Input Voltage: 12V, 15V or 24V
- Output Voltage: +/- 12V
- Output Current: +/- 35mA (Positive Rail draws 31mA, Negative Rail 15mA)
- Ideally: Low Coupling capacitance between primary and secondary
These are the parts I tested:
- Traco Power TMR 1223
- Traco Power TMR3-1223
- RECOM RB-2412D
- Murata MEA1D1512SC
Can anyone help with a "proven in use" part recommendation?
Best regards,
Wolfgang