Power consumption of openThread MTD node.

[jhc]

Hi, everyone

I am studying openthread.

I had a nrf52840 Dongle(running CLI/MTD example) act as MTD node to join in the openthread network.

The Dongle's LEDS were removed, and it was set as below:

> mode
s
Done

>txpower

>0 dBm
Done

> pollperiod 1000
Done

And then I use Power Profiler kit to supply power to the MTD node instead of USB, I get the power consumption as bellow:

then I change the tx power to -20dBm:

> txpower -20
Done

But the power consumption is nearly the same as above picture. It seems that the power consumption has not any change, why?

The avg current showed as above picture is higher than I expected, what can i do for reducing the power consumption? Will the following options work?

1. disable the usb.

2. increase the pollperiod.

3. enable the internal DC/DC.

[jhc]

Hello, Is anyone here? ^_^

[jhc]

Hello, again.

[JONATHAN LL]

Hi jhc,

Sorry for the late reply, there has ben low staffing due to summer vacation.

jhc said:

But the power consumption is nearly the same as above picture. It seems that the power consumption has not any change, why?

Reducing the tx power does not necessarily have a huge impact on the power consumption. 


Yes enabling the internal DC/DC should help reduce the power consumption.

Disabling the USB might also help reduce the power consumption but I am not certain of the impact as I have not tested this myself.

Have you tried the online power profiller? https://devzone.nordicsemi.com/nordic/power/w/opp/2/online-power-profiler-for-ble

Here is a link on power optimizing that might be of interest https://devzone.nordicsemi.com/nordic/nordic-blog/b/blog/posts/optimizing-power-on-nrf52-designs

Link to a different case on the nrf52840 dongle power consumption, https://devzone.nordicsemi.com/f/nordic-q-a/49572/what-is-lowest-power-consumption-template-code-for-nrf52840-dongle

Again sorry for the late reply

Regards,
Jonathan