sleep current with timer running using LF clock LFINT

[Jake.Boyd]

I am using the nRF52832. 

I want to go to sleep in absolute lowest power mode possible that still allows a timer for wakeup.  Using LFINT. 

I don't need ram retension, etc.  Just a timer (30min-1hr). 

What is the relevant spec for the current draw in this mode and

where do I find these current specs in the datasheet?

[Stian Røed Hafskjold]

You can wake the chip up by using the internal RTC. It requires the chip to be in System ON mode.

• System ON without RAM ret: 1.2uA
• LF clock running: 0.25 (external crystal) or 0.6 (internal LFRC)
• RTC: 0.1 uA

So this sums up to 1.9uA when using the internal LF clock.

Numbers can be found here:

http://infocenter.nordicsemi.com/topic/com.nordic.infocenter.nrf52832.ps.v1.1/pmu.html?cp=2_1_0_16_0_0_2#unique_498092668

ION_RAMOFF_RTC

System ON, No RAM retention, Wake on RTC

1.9

µA

By using an external timer you can put the chip in system OFF mode.

IOFF_RAMOFF_GPIO

System OFF, No RAM retention, Wake on GPIO

0.3

µA