I’m having some problems with my newly acquired pHAT DAC. When I connect it to my Pi Zero, the Pi completely refuses to power up. The Pi powers up on its own, and also if I attach another hat (JustBoom Amp Zero).
I suspect the problem is either my beginner-level soldering (my first ever attempt) or that there’s something wrong with the pHAT DAC.
I suspect the possible short between 5v and 3.3v might be your problem.
Without adding any more solder, just touch the tip of your iron to each joint and hold it there for a couple of seconds until the solder forms a neat cone- like a volcano- around the pin.
There’s a couple of other shorts which would also benefit from the same treatment.
The key thing about soldering is that the iron is to heat things up, not to paint solder on. Don’t use too much, but make sure there is some on the iron (it is “tinned”) to get good thermal contact to the pins or whatever.
Warm everything up, then apply the solder and let it flow and make the joint. Use enough to make a nice smooth one, but don’t overdo it. Less is definitely more here.