I have a circuit with a SuperCap used as a battery. I want to know the curve of SC voltage in time to finnaly measure its self-discharge.
Is this can be done with a simple arduino or another microcontroller throught the ADC if I programm the ADC with interrupts every hours for example ?
The idea is to avoid to the maximum the leakage current in the ADC, to perform a reliable measure in time. I found that ADC on the arduino as a Impedance of approximatly 6 MOhms, does this permit the measure I want ? There will be of course a voltage drop in the arduino.
The other option is to seperate the measure points and the SC with a relay commanded by the arduino when it has to make a measure.
The process will act the act with the followings steps :
Wait for interrupt, Relay = open: no measures
Time interrupt (every hour), closing the relay
Read the SC Voltage,
End of interrupt, opening the relay
Wait for interrupt
What do you think about this second method ?