Low-power for nrf52

[Artur]

Hi,

I am trying to develop low power beacon on nrf52.

Which example should I base on?

I am trying example ble_app_blinky on PCA10040, and I am getting close to 1 mA, but I need something closer to 10uA.

In this example in main loop there is sd_app_evt_wait() so shouldnt it work?

Regards,

Artur

[AndreasF]

Hi.

Try the following steps:

1. Disable the logging by editing the following in sdk_config.h:

// <e> NRF_LOG_ENABLED - nrf_log - Logger
//==========================================================
#ifndef NRF_LOG_ENABLED
#define NRF_LOG_ENABLED 0
#endif

2. Enable the DC/DC regulatorby calling sd_power_dcdc_mode_set(NRF_POWER_DCDC_ENABLE)

3. Increase the advertising interval APP_ADV_INTERVAL

I hope this works for you.

Best regards,

Andreas

[Artur]

Thank You for quick reply but it lowers current to circa 640uA. Not there yet.

sd_power_dcdc_mode_set(NRF_POWER_DCDC_ENABLE) before main loop?

I am using s132 and SDK14.2.0 because I want to do final project on nrf52810. Can SD or SDK be a problem?

[AndreasF]

Hi.

How are you measuring the current? I get 1.7µA:

If i include the advertising I get around 460 µA on average:

You can call sd_power_dcdc_mode_set() after you have enabled the BLE stack, note that my measurements does not use the DC/DC regulator.

Best regards,

Andreas

[Artur]

I am measuring with multimeter. I could get on it 3uA on my nrf51822 beacon when not advertising. I will do some tries with digital oscilloscope.

Did You get such results on PCA10040 with ble_app_blinky?

[AndreasF]

Hi.

Yes, I have used a nRF52832 DK which i programmed the ble_app_blinky onto, and I have disabled logging. I have used the Power Profiler Kit and the nRF Connect for Desktop Power Profiler application to measure the current.

Best regards,

Andreas

[Artur]

I am keep getting results near 700mA. I have been trying beacon and blinky examples.

I disabled log, set dcdc, increased interval etc. I am trying examples on PCA10040 not on my board to exclude hardware mistakes.

Have You got any more hints?