A while ago I started a solar charge controller project. It took me a while to understand how my one circuit worked. I did it all with help from a simulation on my Android. I have a question about what I’m seeing in the upper right hand corner of this screenshot:
I am noticing that on my current source where the negative side is grounded and on the positive side there is a small cap and the end of the cap is grounded. Sometimes in my simulator power will oscillate back and forth between the two grounds. Why is it doing this? I’m talking about the logic gate assembly with the current source and small cap.
Why it oscillates? Probably because that seems to be a 1kHz signal voltage source (I don’t know how the app you are using works). And the only thing connected to it are the top inputs of the 2 logic gates, which are likely to have high input impedance/resistance, so current can only oscillate across the capacitor to those ground connections.
If I understand those squares on the wire correctly as indicating current intensity, the the faint squares (greyish) indicate that very little current flows into the logic gate inputs, compared to the capacitor (green).
P.S. The bottom inputs of the 2 logic gates are floating, so you can’t be sure of what the output is doing. Atleast not in reality. In this case, who knows how such a simulation behaves. It’s to the whims of the Math-gods.
Valen said: P.S. The bottom inputs of the 2 logic gates are floating, so you can’t be sure of what the output is doing. Atleast not in reality. In this case, who knows how such a simulation behaves. It’s to the whims of the Math-gods.
This is absolutely correct. The bottom of the And gate input and the bottom of the Nor gate input are tied together and must connect to the positive rail or ground. Not having this will cause funny circuit operation.
The 10nf cap looks like a poor way for some signal conditioning, you should remove it.