Hello, i'm using a resistor ladder to simulate 16 cells voltage to test adbms1818 chip. Since this testing rig will be running for a few hours i'm worried the resistance will change due to thermal reasons and i can't check if the adc accuracy. Is there a way to stabilize the "cell voltages" so they wouldn't change because of the thermal changes but also would change when i toggle cell discharge (closing a mosfet to discharge the cell through 6 ohm resistor)? Sorry if this is a dumb question with an obvious solve this is my first bigger project.

 

Hello, i'm using a resistor ladder to simulate 16 cells voltage to test adbms1818 chip. Since this testing rig will be running for a few hours i'm worried the resistance will change due to thermal reasons and i can't check if the adc accuracy. Is there a way to stabilize the "cell voltages" so they wouldn't change because of the thermal changes but also would change when i toggle cell discharge (closing a mosfet to discharge the cell through 6 ohm resistor)? Sorry if this is a dumb question with an obvious solve this is my first bigger project.
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I wonder if a set of zener diodes might help you achieve a better solution? do any of the loads placed on the various output pins, vary? Also precision foil resistors are very stable, with like +/- 1ppm per deg C

 

Welcome to AAC!

Since this testing rig will be running for a few hours i'm worried the resistance will change due to thermal reasons and i can't check if the adc accuracy.

What is the input impedance of the circuit reading the voltages?

If it's in the megaohm range, you could increase the value of the resistors by an order of magnitude. That would decrease power dissipation, and the associated heating, by an order of magnitude. You'll have to use higher precision resistors (or cherry pick values) for the most accurate results.