Hello everyone.
I have an Atmega328P on a breadboard with a minimal install of VCC, GND and AREF (5 pins total). I'm supplying a constant 3.3V and my DMM does in fact read 3.3V on the breadboard +/- rails. When I hook up the Current Ranger and turn it ON, my DMM still reads 3.3V on the breadboard +/- rails, however, when the current ranger is OFF the DMM reads 2.85V.
I have tried the same test above with 3.7 Li-on batteries outputting 4.17V and I got the same loss, -0.45V when the Current Ranger is OFF.
I also tried with a 5V power supply and got the same results.
Note: I'm not sure if this is related but, when I disconnect the GND pins from the Atmega328P, the problem goes away.
Any thoughts on what might be going on here?
Thanks!
Lenir