I have strange problem with 3590s 10 turns precision potentiometer. Sometimes pot readings jump during operation. When I checked resistance using multimeter (after disconnecting it from circuit), got following observations.
- VCC to Wiper pins : resistance varies
- VCC to GND pins : resistance varies
- GND to Wiper pins : resistance stable.
My understanding was that wiper in issue can make resistance jump, since that's the moving part. But above observations says something wrong with VCC pin, but my understanding is that it's stationary pin so nothing should probably go wrong with it. Is my understanding correct?
And, if there is something really wrong with VCC pin of pot, can I bypass it altogether using a external resistor as shown in following diagram? Maybe I will not get full 0-1024 signal range on analog pin, but as long as I get signal stability, I can work with it.