Power switch bounce

Here’s another one for eventual future board revisions: the PONSW line needs debouncing. With the case I’m using (Fractal Design Define Nano S), powering the board off via the power button is nearly impossible, as the board will almost always immediately power right back up. The PMIC manual is pretty clear that it expects any switch inputs to be debounced.

I assume the same goes for the PORESET_N line, but there’s no readily visible side-effects from it bouncing.

Hi Anders,

Thanks for the feedback on the front panel power button.

Can you describe the fail scenario where the board powers on after powering off in more detail?

How long do you hold the switch?

Are you able to repeat this behavior using the on board power switch?

I couldn’t find much info on the Fractal Design Define Nano S switch online. I’m expecting this to be a passive switch with no circuitry.

Can you confirm the front panel connectors are plugged in correctly and there’s no issue with crimps or connector pins or connector alignment? This connector isn’t keyed or shrouded to ensure correct alignment.

There is an RC network to deglitch the signal in the design but maybe this isn’t effective or there’s a manufacturing issue with your board?

Well, that’s embarrassing. It seems that while experimenting with the PMIC, I managed to put it into a state where it automatically restarts. After physically removing all power from the system, powering off now works properly again.

Apologies for the noise.

No worries, if you weren’t using your board you wouldn’t have made a mistake :slight_smile: and it’s debatable that this was a mistake because some folks are looking for this auto power on functionality.

Thanks for being an early adopter and experimenter.

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