MP34DT05-A current consumption

[AZ.2]

Hi ST team,

I use MP34DT05-A microphone in my design and I measure an addition of ~8.5mA to the average consumption current while the microphone is active.

The datasheet specifies 650µA consumption in normal mode, and up to 10mA short-circuit current.

Sorry for my newbie questions but can you help me understand what exactly is the short-circuit current in a microphone? Is it possible that I am operating the microphone incorrectly?

Thanks!

[niccolò]

Hi @AZ.2​ ,

the short circuit current is the maximum current flow that the device can safely withstand, but the current consumption should be around the 650 uA declared by the datasheet.

could it be that the microphone went through an Electro Static Discharge? this could have damaged the device, causing the consumption to go through the roof.

another thing that you can check is if it is really the mic that drains so much current, by disconnecting the power at the Vdd pin.

Let me know if this helps you.

Niccolò

[AZ.2]

Hi @niccolo.ruffini​ and thank you for the reply!

If I understand correctly, the short-circuit current is the Vdd current. Is it possible to manipulate this current to be higher/lower?

I don't think it is an ESD issue since I measure it on several boards, but it is possible that this increased current consumption origins from the MCU itself and not from the microphone, as you suggested.

Do you have any data regarding the expected consumption current from the MCU side during normal operation and communication with the microphone?

Thanks again

[niccolò]

Hi @AZ.2​ ,

the power consumption of the MCU should be written on the datasheet, but without knowing what MCU you are using, I don't know which is it.

Niccolò