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Andreas-Dorfner / Powerline-USB-C

Powerline is a small 3HP Front Entry USB-C eurorack power supply.
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wierd voltages #1

Open KeLaiFu opened 1 month ago

KeLaiFu commented 1 month ago

I've built one of these and I am getting -12 and 5v on the header, but 4.9v on the +12. I checked the power coming from pin 1 on the IC, and its 1.3v (?) but 4.6v on the VBUS pin on the other side of R1.

I'm using meanwell DC blocks and ICs from LCSC and with such a small BOM, I am at a loss...

Any ideas?

Andreas-Dorfner commented 1 month ago

I'm sorry your module isn't working as it should. The good thing is the voltages you measured mean that most of the module is ready to go. As for the rest: The first thing to check is if the USB-C brick you are using supports 20V and the PD protocol(Other protocols are not supported). If that is the case, that would indicate a problem with the USB-C trigger Circuit around the CH224K. I still need to build the USB-C version of this module jet, so I can't confirm if the problem is in the schematic or your particular build. However, as you are using genuine parts, I highly suspect that the default implementation in the CH224k datasheet is faulty. As a quick fix, if you supply the module with 20V through the USB-C port with a rigged cable (like a USB-C trigger cable) or a barrel Jack, it will work for now. I will review the USB-C trigger section again and update you if I find an error.

KeLaiFu commented 1 month ago

OK, thanks for the update. the USB-C power source I am using states 5A / 20V and powers my new laptop without issues so I think that is ok. I tried a second one which is lower spec and the results were the same.

If you need me to test / try anything let me know.