When designing a DIY electronics project, how you supply power – e.g. a battery and charging circuit – often comes late in the design process. After all, people have been powering projects for many years. That part should be easy.
Or so you might think. This fundamental power supply technology continues to evolve. If you need something that fits your needs perfectly, sometimes the solution is a new custom board like the one DIY GUY Chris made.
His circuit connects to a USB-C power supply and passes the appropriate power along to a battery via a BQ24075 charging IC. The board then takes power from the battery and boosts it up to 5V with a PAM2401 IC.
It’s a relatively simple concept. The board should allow a nominal 3.7V battery to supply a clean 5V output down to .9V (when nearly dead), then charge it appropriately over and over. And it does the job… after a significant bit of troubleshooting seen in the project video below.
In addition to showing off the charge/boost circuit design, the video outlines DIY GUY Chris’ process when it didn’t quite work as he’d planned. This meant first mitigating a solder bridge, but there was actually a more fundamental problem with the board that took some investigation to find. However, this too was easily fixed once found.
I won’t spoil the video entirely (see just before 12:00 for the reveal)… but remember to check your drawings if you’re going to recycle a circuit section on your schematic!