Dual Power in a Snap

Recently I needed a dual voltage power supply to test a newly arrived PCB, but my usual lab power supply beast was temporarily at a customer site. I had a FNIRSI programmable power supply which would have been perfect, but alas I only had one. Digging through my junk box, I found several USB-C power “trigger” boards that I purchased for an upcoming project. These seemed almost too small for the task at hand, but after some research I realized they would work just fine.

The ones I had used the Injoinic IP2721 USB-C power chip, commonly used in many of these boards. Mine had been sold pre-configured for certain output voltages, but they were easy to reconnect to the voltages I needed, +5 VDC and +20 VDC. The hardest part was using them physically – they’re the size of a fingernail. This build had through-hole output pads on 0.1″ centers, so I decided to solder them to the base of a standard MTA pin header. A few crimps later and I was up and running, with the required pair of USB-C cables and power adapters.

For just a few dollars each, these trigger cards are useful to have in your toolbox, both for individual projects and for use in a pinch. We looked at these modules a few years ago and found the much more flexible PD Micro that we covered last year.

Alan A. Seibert