GPIOTE IN_EVENT Current

[Cory Mast]

Hello,

I am currently using the GPIOTE Driver (nrf_drv_gpiote) to detect external interrupts from a sensor on a custom board using the nRF51822 with the S130 v2.0.0 SoftDevice and SDK 11. I currently have the interrupts setup to use the GPIOTE IN_EVENT instead of the PORT event because I need to detect fast changing signals that are missed when using the PORT events. I have been looking through other posts on the Devzone and I am aware that using the IN_EVENT over the PORT event will increase the current consumption which is fine during normal operation. The problem I am having is that when I attempt to enter and Idle/Low-Power state (not System Off), I can't seem to reduce the current from the ~1mA that I am seeing after the interrupt triggers the IN_EVENT.

I have tried everything I can think of but no matter what I do I can't reduce the current consumption. I have tried:

• Using nrf_drv_gpiote_in_event_disable(pin) to disable the interrupt
• Using nrf_drv_gpiote_in_uninit(pin) to uninitialize the module for the pin
• Using NRF_POWER->TASKS_LOWPWR = 1 to turn off the HFCLK (suggested by Ole here)
• Using NRF_CLOCK->TASKS_HFCLKSTOP = 1 to stop the HFCLK
• Using every combination of the above

I am using NRF_CLOCK_LF_SRC_XTAL as my clock source and I am certain that the GPIOTE IN_EVENT is causing the increased current consumption. When I enter the idle state mentioned above, I am calling sd_app_evt_wait() until I leave the idle state.

Is there anything I can do to reduce the current consumption after a GPIOTE IN_EVENT is triggered?

Any help anyone can offer is greatly appreciated.

Thanks!

-Cory

[Hung Bui]

Hi Cory,

There is a chance that you were still in debug mode when you test. You would need to make sure you do a power reset after programming to get out of the debug mode, before you do any measurement.

I just did a quick test here with the pin_change_int example in the SDK. I added __WFE() in the main loop, and then added nrf_drv_gpiote_in_event_disable(PIN_IN) in in_pin_handler() after that I can see the current consumption dropped after I pressed the button.

[Cory Mast]

Thank you for your help Hung Bui, I added the nrf_drv_gpiote_in_event_disable(PIN_IN) to a scheduled event and I can now see the power drop before and after the event is executed by the scheduler.

Thank you very much for your help!

-Cory