Other Parts Discussed in Thread: ADS1262, LMP7721
I have 100 custom boards each with four LP3985IM5-2.5/NOPB voltage regulators.
So far I have found six LP3985 regulators that don't output +2.5V. I have checked the capacitors to ensure the right ones were put on the board.
The voltages on the pins are,
V(Pin1-GND) = 5.16V
V(Pin2-GND) = -0.273mV
V(Pin3-GND) = 5.164V
V(Pin4-GND) = -0.449V
V(Pin5-GND) = -0.609V
Replacing the LP3985 does not appear to fix the problem.
Sometimes the regulator will randomly start working.
Does anyone have any suggestions on what could be wrong?
Thanks,
Allan