Hi team,
I've been experiencing some issues with INA240, and I'm hoping you can help. In short, the INA240 is reporting incorrectly as we allow our boards to heat up. I am sensing unidirectional current (25A max) through two 2mOhm resistors in parallel. Both INA240 reference pins are tied to GND, and Vs = 5V.
During this test, the channel is PWM'd from 30% to 100% and turned on at 20kHz for 250msec. At room temperature, the device measures accurately. But when the boards are taken to 85C, the output of some devices are inaccurate. Some devices will read low with or without current flow, some may have inverted outputs (low with current flow, high without current). Returning the devices to room temp does not fix the problem. The only methods of bringing the device back to normal operation that we've found is to power cycle the device.
I am using the 100V/V device (A3) and the following sense resistor: ROHM PMR18EZPFV2L00 (again, using two of these in parallel).
Do you have any thoughts as to what might be the problem?
Thanks,
Brian
