The ADC on AVR's use a sample and hold circuit for it's ADC conversion. Does anyone know what the recommended/max impedance for that sample and hold circuit is? I just noticed the other day looking through a PIC PDF file (helping someone on another forum) that they list the recommend impeddance at 2.5k ohms and the max impedance at 10k ohms, in order to fully charge the capacitor for the ADC reading. What would be the equivilant values on an AVR? This is in concern to using 2 1 meg resistors as a voltage divider for a battery monitoring system.
Joined: Mon. Aug 4, 2003
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