Due board making audible noise

My Due makes annoying audible noise when board is powered from USB or 5V pin directly from PSU. Noise goes away when powered form Vin pin by 12V from PSU. Tried to use USB power from battery bank instead of powering USB from my laptop, but it doesn't seem to make a difference.

I have located that the source of the noise is coming from the area next to DC jack. Probing around this area with oscilloscope I found that there is a 3.1kHz ripple (about 100mV amplitude) across 47u electrolytic capacitor (PC1 in the schematic). When I press reset button, both ripple and noise seem to go away. Also tested another Due board which doesn't make this noise, and there is no ripple on it across PC1.

Does anyone know or have any thoughts about what might be causing this? I have included screenshots of the schematic and oscilloscope trace.

possibly the switching regulators?

Mine is doing the same. Have you solved it? A least do you know the cause? I don't know if it is the voltage regulator or the cap? (I don't have a oscilloscope) It is a disturbing pitch noise. It is not present when powered by the jack plug.

i had that problem a while ago but only when using the native port, didnt hapen on the programming port

I know this is an old thread but Im experiencing the same problem. Did you solve this? THe difference for me is that I only have it on the DC jack not the USB ports.

Ask a refund from your reseller :slight_smile: