USBC Output power on AMD Laptop 13

Hi All,

I’m using a FW motherboard for a project and I am just discovering that the USBC ports don’t allow USBC PD negotiation for power out.

I am ultimately attempting to get 12v to power a 10w PCIE card. I initially thought that it was just 12v that couldn’t be requested, but just tried 15v as well and no dice.

I have read on another topic just now regarding the FW13 that “3 ports support 5v 1.5a and one of the four can request 5v 3a”

I just wanted to check this is still the case with the AMD board, and if so is there anything special to the power negotiation of the 5v (i.e. does it have to have a USB C chip/trigger) or is it just the line voltage of the USBC port?

At the moment I’m guessing stepping up this 5v output is going to be my only way to get to 12v

If there is any other way to get 12v out of the motherboard I would love to know!

According to my testing, the USBC output is 5V3A PD and the input is any PD <=100W except 5V3A

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Ok great thanks, and I am just reading that you do in fact need to use a USBC ‘trigger’ to get the 3A output from the board.

For just 5V you should only need the cc resistors not a full blown trigger.

Yea think I may have misunderstood that, although it looks like pre-made boards with just the resistors are less common, unless in breakout style.

If you want an off the shelve board a full blown trigger bay be the easiest, they are quite cheap.

If you want to integrate it in a board a trigger for just 5v is overkill.

I could make a custom PCB for it but as you said - triggers are so cheap it may well be the simplest/easiest way. It isn’t part of a larger PCB otherwise I would absolutely just do it that way!

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