nRF52840 - System ON mode with RTC wake-up and Lowest power consumption as possible

RE: nRF52840 - System ON mode with RTC wake-up and Lowest power consumption as possible

Stian Røed Hafskjold — Tue, 09 Apr 2019 12:05:56 GMT

Is 1.2 mA with DCDC enabled? And are you using nRF52832? If so, this number corresponds well with the HF clock and DMA bus being active. Sometimes the SPI and TWI will not release the clock if they are not disabled properly. Can you please post some code showing how you disable the peripherals?

There's more info about this in these posts:

https://devzone.nordicsemi.com/f/nordic-q-a/37754/putting-i2c-peripheral-back-into-lowest-power-state/145646#145646

https://devzone.nordicsemi.com/f/nordic-q-a/26030/how-to-reach-nrf52840-uarte-current-supply-specification/102605#102605

In the workaround proposed in the above two posts please change the xx part of the register address to the peripheral you are using: 0x400xxFFC

You can find the base address for the different peripherals here: https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.nrf52832.ps.v1.1/memory.html?cp=2_1_0_7_3#topic

RE: nRF52840 - System ON mode with RTC wake-up and Lowest power consumption as possible

Circuit Designers — Mon, 08 Apr 2019 13:20:13 GMT

i am already doing all three points you told me to do.

By doing those i am getting 1.4mA current after disabling all and doing all you mentioned.

Our BLE chip is consuming 1.0mA to 1.2mA current out of 1.4mA.

Any further solution ?

Thanks

RE: nRF52840 - System ON mode with RTC wake-up and Lowest power consumption as possible

Stian Røed Hafskjold — Mon, 08 Apr 2019 12:24:57 GMT

Hi,

A) You should stop and disable the SPI, TWI and timers (TIMER peripheral, not the RTC timers).

B) You stop and disable the peripherals pretty much the same way as you enable them, using the SDK libraries.

C) After all the peripherals are stopped, you need to put the CPU to system ON idle mode, which is done by running __WFE() in a loop

RE: nRF52840 - System ON mode with RTC wake-up and Lowest power consumption as possible

Circuit Designers — Mon, 08 Apr 2019 10:03:08 GMT

Hi,

Any Suggestion ?

Thanks

RE: nRF52840 - System ON mode with RTC wake-up and Lowest power consumption as possible

Circuit Designers — Mon, 08 Apr 2019 09:55:10 GMT

Hi,

Any Suggestion ?

Thanks