I'm in search of a power converter that can take a USB-C PD input of 100W and output 12V with at least 72W. The device I need to power works on 12V DC through a barrel plug, and while USB-C PD can supply the necessary wattage at 20V (100W mode), it only manages 36W at 12V (3A). I really need at least 6A. I could make a solution with a USB-C PD trigger and a buck converter, but I'm wondering if there are any ready-made options available that fit this requirement, as most I found just pass through the power from the USB-C charger at its native ratings.
3 Answers
The way USB-C PD operates, there’s a 5-amp limit which means you'll find it tough to get more than 60W at 12V. Your best bet might be to look for a product that converts 20-24V to 12V, accepting a 100W input and stepping it down. That’s probably the most practical solution for your power needs.
It looks like you might need to build a custom solution. I’ve searched for something similar, especially for powering my telescope that requires 12V. I'm using a power pack with both a barrel plug and USB 3.x that delivers 12V through PD, but it keeps shutting off due to low average current. To solve this, I'm considering building a 15V to 12V regulator or using a USB dummy load to keep the power pack running.
Most power supplies need a minimum load of around 100mA to stay on. You could use a 50-ohm, 1-watt resistor on a USB plug or even a red LED to keep it alive while you're using your scope.
Have you thought about using an inverter? You could convert the 5V/20A to 110V or 220V, and then plug a 12V power supply into the inverter. This might not be the cheapest method, but it could work.
If that’s the case, I might as well stick with the original power brick. I’m really aiming for a more compact solution, and I figured 100W USB-C should work just fine.
If you have a mobile phone, try plugging it into the other 5V outlet; that should give enough load to keep it operational.