How would one approach measuring Capacitor ESR?
Hi, I have done a PIC 16F628 based pico-capacitance meter.
I know there are a lot of other designs around but this one is very quick to build as it just uses one IC, the PIC (as it uses the PICs internal comparator as the oscillator).
It measures down to 0pF and reads in 0.01pF resolution in the bottom range, up to about 18000pF.
Total measuring range is 0pF to 50uF. It only needs a decent 10k 1% resistor and will be calibrated so ideall you won't need any special caps or test equipment to build it.
The schematic, PIC HEX file and photos etc are all here;
Roman, dont be offended in any way... i simply dont own any 16F628's and i wanted to see if i can do it also. Its not a clone of your work at all. I can draw you a schematic if you want. my code is also small.Atom, why do your own version when mine is fully finished and tested and the PIC hex file is included? There were a few clever firmware tricks I used to ensure very high resolution and math precision, and it was not easy to fit it all in a 2k PIC. It has also had quite a bit of testing against good frequency meters and other cap meters. Why try to duplicate tricky hard work when it's already been done for you?
Sahu, most multimeters read large capacitor values, it is the small caps that can be hard to read. Also large caps are very clearly marked so is never doubt as to what their value is.
I'm not offended! The reason I put hobby work up on my web page is so people can enjoy it and benefit from it.Roman, dont be offended in any way... i simply dont own any 16F628's and i wanted to see if i can do it also. Its not a clone of your work at all. I can draw you a schematic if you want. my code is also small.
Its less than 4k which is good for most PIC18F series. Also i might make it USB so you get the value in a nice windows application