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LPM01A immediately stops due to overcurrent

Associate II

I've tried two different boards: one is a custom PCB that should never draw more than 8 - 10 mA and another is a Teensy 3.2 with a Blink example loaded onto it.

In both cases the LPM01A either fails to provide a high enough voltage (for the custom PCB, it's set to 3.0 V and provides around 1.6 V, for the Teensy, it's set to 3.3 V and provides 1.6 - 1.8 V), or immediately fails due to overcurrent.

The custom PCB works with a 3.0 V coin cell and I doubt the teensy is drawing more than 60 mA...

What can I do to solve this issue?

Please also take a look at my other question for something that might be related... having lots of issues with this board so far...

Associate II

I think I may know the answer. There is a capacitor on both boards that could be drawing a large current when first powered on that trips the overcurrent protection.

Removing the 2.2 uF decoupling cap on the LPM01A seems to help a bit. I can get it to measure properly, but the overcurrent still trips intermittently.

I wish this was something that could be avoided, but I guess it's fine.

ST Employee

LMP01A is not designed to deliver more than 50 mA. If the current exceeds 50 mA even for a very short period of time, it is normal for an overcurrent to be detected.

Can a current surge generate a current of more than 50 mA on the customer's product ?

Also the new STLink V3 PWR (STLINK-V3PWR - STLINK-V3 compact in-circuit debugger and programmer for STM32 - STMicroelectronics) , is designed to deliver up to 500 mA.