Almost a year ago, I installed white strip lights on a home entertainment unit with a dimmer system that uses an ATmeag328p. Yesterday, we found it wouldn’t power on, so it was time to reopen this time capsule. I like to think of it as a time capsule because it reflects on what I knew a year ago. In this quick post, you’ll see what I mean by that.
After a few pokes with my multimeter, I found that there was no power getting to the ATmega328p microcontroller. I thought it may have been a problem with the LM7805 regulator so I swapped it out (which is why it’s missing in this picture). That wasn’t it. With a few more pokes from my multimeter, I found it was a problem with the switch. For whatever reason, the switch wouldn’t close between the two pins I was using. The other side still opened and closed fine so I just moved one of the wires over to use that side of the switch.
While I had the project open, I decided to do a little updating to it. At the time, I was experimenting more with standalone ATmega328p’s so naturally this project ended up being powered by one. It was overkill since the system only uses one PWM output and one analog input. I switched the ATmega328p out for an ATtiny85. You could still say it’s overkill since I could use a 555 timer, but it’s a cleaner and simple solution. I also hot glued some of the connections as a way of insulating them, instead of using electrical tape that sometimes falls away and gets gross after a while. I was considering trying to solder this circuit onto a perfboard, but I’ll leave that for another time.
So that’s the update! I always like revisiting projects where I can make meaningful improvements and optimizations. Thanks for reading!