Measuring Deep Sleep Current

Greeting,

I want to measure the current consumption of my STM32 in deep sleep. While I was looking for some examples about measuring very low current with dmm. I read something called brownout detetection. As I understood from some forums, I can not measure micro amper consumption in a microcontroller(DMM is set to uAmp mode). However I have to measure current consumption in deep sleep.

What can you suggest?

Thanks.

An internet search using the words "measuring MCU sleep currents".

Thanks for the answer.

People recomend using a resistor and measuring the voltage drop accros it, but I don't want to measure it with a resistor. My question is.
Is a good DMM able to measure MCU deep sleep current?

Yes.

Thanks for the answer.

I didn'know that.

Can you give an example?

Did you do a search on the internet using the words, "example measuring mcu deep sleep current"?

I could do internet search for you, for a fee, if you'd like.

Thanks for the answer. :yum:

I found out that in DMM's datasheets there is a section called burden voltage and it shows that the burden voltage in all ranges.

Let's say that my normal mode current is 200mA max and my deep sleep current is 5 uA. I can set the DMM in mA this will cause 0.36V in 200mA. If I power the mcu with 3.3V mcu will get only 2.94V. That is not a problem in my opinion. I can easily measure both normal mode and deep sleep at the same time.

Correct me if I am wrong. I am just making guesses that are based on some internet research.

You need a multimeter on uA and a bit of wire or a switch, details here;

Thanks for the answer.

Was my guess wrong?

Wow. It is very simple.

Thank you. :slight_smile: