Using up some old Qi chargers

A project log for Use It Up!

Documenting my efforts to use up the various electronics bits and pieces I've collected over the years.

dan-julioDan Julio 11/12/2023 at 19:190 Comments

I had a couple of Qi charger circuit board kits I got from Adafruit and from a client project. 

A small Eureka moment ensued when I read my iPhone supported Qi charging as well as Apple's proprietary wireless charging.  For some reason I still had the box the iPhone originally came in and it turned out to be a perfect dimension to hold a Qi transmitter and easily align the phone over it.  A little cutting with an X-acto knife, a little hot glue and a cut piece of 0.25mm thick styrene modeling plastic and I had a bedside charger.  I did have to put a piece of black electrical tape over the blue LED on the transmitter to prevent what looked like a nuclear accident from lighting up the ceiling over the night stand.  I'm glad the era of Blue LED power indicators is over.

I still had another transmitter and one good receiver (the other was damaged it turns out during an experiment).  So a quick OpenSCAD design made for a second 3D printed charging base.  The modeling plastic is attached using double-sticky scotch tape.  The design is included as one of the project files -

A couple of black plastic nuts glued over the transmitter LEDs made for very nice circular charge indicators visible through the top surface.

And then I hacked my gCore based hex calculator to include one of the wireless receivers.  The Qi charger just connects to the USB 5V line and ground.   It can deal with USB power being applied too so there was no need for any isolation circuitry.

The calculator also includes an accelerometer used to automatically power it on when picked up.

All-in-all a set of pretty quick little hacks with very useful results.