Question about ADC power consumption

[Scarlet]

Hello, I am trying to develop a low power application by using nrf51822 EK board.

In " Reference manual v2.0, 11.1.3 System ON mode ", it says there is a mechanisms can automatically switch on and off the appropriate power sources depending on how many peripherals are active.

One of my application needs to detect the coin battery voltage I use ADC with TIMER2 to detect it. The detection period is relatively long (60~120 sec perhaps) I want to know when I enabled the ADC's interrupt (Avoiding interfere realtime application), Will the ADC is always "power on" even in IDLE state?

To reduce power consumption If the answer is yes, I think I can change my code by enabling ADC interrupt after the TIMER comparing event happens...

Thanks!

[Ole Morten]

Any peripheral is enabled and powered on from you enable it (typically through an ENABLE register or a START task) until you disable it (typically by writing a disable value to ENABLE or triggering a STOP task). As for the ADC in particular, it will be enabled from you write the enable value, 1, to the ENABLE register until you write the disable value, 0, to it

You may have use in taking a look at this question.

Also, beware that TIMER2 requires the 16 MHz clock running, and will hence consume ~1 mA of current. If you want a low-power timer, you should use the RTC. Take a look at section 8.3 of the PS to see which peripherals needs which blocks.

[Scarlet]

Thanks Ole!! I will modify my code to use RTC!