12V trigger output from a PC

[jazd]

This is a quick guide on how to power on an amplifier or DAC when your PC turns on (and off when it turns off).

1. Get a USB to 12V converter
   1. Note: don't get one that depends on USB PD (Power Delivery)
   2. e.g. https://www.amazon.com/dp/B09NSHWLV9
2. Get a 3.5mm audio connector
   1. e.g. https://www.amazon.com/dp/B07QPL3S7C
   2. Or use a soldered connector for a more streamline cable
   3. Note: a mono 3.5mm connector (TS 2-wire) seems to be more common, Fosi uses a TRS (3-wire) connector however
3. Wire the 3.5mm audio connector to the USB 12V converter
   1. Cut the barrel connector off the USB 12V converter's cable
   2. Screw the wires into the green terminal block
   3. My Fosi ZD3 requires 12V to the tip of a TRS connector which is the left channel on the terminal block
4. Plug your cable into your trigger input on your amp/DAC
5. Make sure Windows "fast startup" is disabled if using Windows
   1. This adds around 10s to my boot time
6. If you still have trouble make sure your BIOS/UEFI has the "USB power delivery in Soft Off state (S5)" setting set to "Disabled"