I have a MiniGen from SparkFun. I am trying to get 1-100Hz out of it. So far, the MiniGen can produce this, but the output is offset by a Vcc/2, about 1.6VDC. I suppose the offset is due to the power being 3.3VDC. To remove the offset, I put an AC coupling capacitor in series with after the MiniGen.
The problem is after the capacitor when I pass the MiniGen signal through a voltage follower. I get another offset. I don’t see an offset after the capacitor, but I see an offset after the voltage follower.
Oddly, the offset after the follower goes away by increasing the coupling capacitance to 1uF. Another way to get the offset after the voltage follower is to load the cap with a large resistor about 1MOhm.
Does anyone know why there is an offset after the voltage follower? The follower should just be 1-to-1 with its input.