I have built a 3.3 volt power supply, to run my microcontroller and a microphone/op amp, out of a step down transformer, a full wave bridge rectifier, a 100microFarad capacitor, and a 3.3voltage regulator. This is tapped off of a standard 110 wall supply. In series with the transformer, I have a triac switch which turns on/off a load (in my case, a light bulb). I can't figure out why but when I turn on the power, the 3.3v dc line has a pretty significant ripple on it. When I turn the lightbulb off (using the triac switch) the dc voltage has no ripple. Also when I take the amplifier and microcontroller off the 3.3volt line then my dc voltage looks fine. Any ideas why this may be happening? I put in like 12 100microfarad decoupling capacitors in parallel and I was able to smooth out the dc line pretty well. But there has got to be a better way..
I initially thought that maybe my voltage regulator wasn't big enough. So I bought one rated up to 1.5 Amps and this did not solve the problem.
I will try to post up a schematic so that this is a little easier to understand.
I initially thought that maybe my voltage regulator wasn't big enough. So I bought one rated up to 1.5 Amps and this did not solve the problem.
I will try to post up a schematic so that this is a little easier to understand.