I guess I’m just not thinking clearly, but is there a simple, low-component-count way of checking multiple voltages that are wired in series?
Lithium Polymer (Li-Po) cells are often permanently wired in series, e.g., 2S, 3S or 6S, with each cell between a cutoff 3.75V and a full 4.20V. The cells have the total voltage wired for general use, and also a second connector that gives access to individual cells for monitoring or charging.
+V <-+-> V3 | = | +-> V2 | = | +-> V1 | = | GND <+-> V0
I’d like to make a simple small-pcb solution that uses an ATmega8 or such, to individually monitor voltages, but I’m drawing a blank on how to simultaneously or dynamically monitor each cell vs the digital AGND of the Atmel chip. If I just wanted to measure one, say V2-V1, I’d just hook V1 to AGND and V2 to an ADC pin, and disconnect the others. I don’t want to disconnect/reconnect individual cells.