power management nrf52840

[František]

Hi, 

I am using nrf52840 chip, there is Thread and iot coap library, and movement sensor. When sensor detect move, pin call interruption and send coap message. 

Voltage is 3.3V and current is 42.5mA

In sleep mode is current 28mA 

I want to use it on battery power. 

How I decrease power? 

Thank you. 

[Simonr]

Hi

Both these values seem to be incredibly high for a single device. What other peripherals are enabled on your device at the same time? It seems like there must be quite a few other peripherals drawing power as well as the nRF52840. Please make sure you disable all unnecessary peripherals as you go to sleep so that they won't draw power while your radio is sleeping.

Have you measured how much power I.E. the sensor detector draws by itself?

As for what you can do to reduce the current on the nRF52840 itself, you can try enabling the DCDC regulator, if running on a DK or a board with the required components and add the following line to the start of your main() loop:

NRF_POWER->DCDCEN = 1;

When the radio is active transmitting or receiving by itself, you should see a current consumption according to the PS here.

Best regards,

Simon

[František]

Thank you, chip was probably broken. Next chip have in active state 17mA and in sleep state 0.45uA.

[Simonr]

These values seem good according to the specification! Do you need any further support or can we close this case?

Best regards,

Simon

[František]

May be closed. Thank you again.