diff amp, line receiver, opamp, comparator, A/D converter and perhaps others too numerous to mention.I need to detect a very small voltage step with a PIC chip. How might that be done?
Unmentioned is my original question was the micropower requirement. Sorry, I forget how many details are needed to explain the whole situation.diff amp, line receiver, opamp, comparator, A/D converter and perhaps others too numerous to mention.
Design problems can be tough when you're deprived of FTF interactions. We used to spend hours (cumulatively, not all at once) over coffee just spit-balling over various problems. Once the boss understood the purpose, he asked if he could join us. It was a wonderful time.Unmentioned is my original question was the micropower requirement. Sorry, I forget how many details are needed to explain the whole situation.
All you need is a comparator to detect when the voltage is around 0.1V.I need to detect a current pulse of 1 mA. I plan to use a 100 ohm sense resistor to develop .1 volts.
You should have mentioned that requirement in your original post so we don't waste our time trying to solve a poorly defined problem.The LM393 draws too much current to run for a year. I need microamps.
Here is a block diagram of what my plan was.
You can make the resistors on the voltage reference an orders of magnitude larger. The output depends on what it will be driving. You could switch to one with an active output. Just make sure the common mode input voltage range goes low enough.I will look for a micropower opamp with which to implement this design.