RE: Simple nRF51822 Power Consumption Examples

Amund Glomsås — Sun, 04 Jan 2015 19:57:40 GMT

I'm not sure wish thread I should post this. But I tried system-on-wakeup-on-rtc on the PCA10006 board and measured 1,5mV on K2. This should give about 15uA. Is there someone who has better result for this, and can tell me how to do that?

RE: Simple nRF51822 Power Consumption Examples

Stefan Birnir Sverrisson — Tue, 23 Sep 2014 13:13:12 GMT

An appropriate code reference for putting the chip into low power mode without using the softdevice, please look at the powerdown examples on the Nordic's Github, specifically look at the system-on-wakeup-on-gpio example to test the System On low power mode current constumption.

For measuring the current consumption for the softdevice, you can run the ble_app_hrs for the evaluation kit, which is power optimized, as stated in the documentation for the example. The ble_app_hrs example for the development board is not power optimized, but you can make it power optimized by enabling compiler optimization. This thread describes how to enable compiler optimization and also contains a lot of good hints on how to minimize current consumption of nRF51 devices.

In our code above, the 700 uA current consumption is normal when using the synthesized low frequency clock, you should instead use a crystal or the internal RC with calibration, see the same thread as I pointed to earlier. For the current consumption without the softdevice, you should measure ~2.6uA, and that is what you should see when trying the low power example I pointed you to earlier for System On low power mode. For System Off low power mode, you should see ~0.6uA with no RAM retention. These current consumption numbers for the different modes are stated in table 27 in the nRF51822 PS v2.0.

Further information on power consumption and current measurements, including troubleshooting is found on this thread