About current consumption of GPIO and GPIOTE

RE: About current consumption of GPIO and GPIOTE

Kosmine — Tue, 06 Aug 2019 07:22:43 GMT

Power usage with low accuracy mode depends on your choice of LFCLK source. It can either be XTAL, RC or synth. XTAL being the ideal choice it doesn't really consume much more power than a few micro amperes. As for accuracy, i don't think the PORT event tells you the pin that generated the event, so you would have to check it at the interrupt. For my purposes the low accuracy mode has been good enough... (interrupts from LIS12DH an so on)

RE: About current consumption of GPIO and GPIOTE

takashina hiroki — Mon, 05 Aug 2019 23:33:37 GMT

Are these things described in the specification document?
If so, please tell me the applicable part.

What is the current consumption in normal mode?
Also, please tell me the accuracy of normal mode and high accuracy mode.

RE: About current consumption of GPIO and GPIOTE

Simonr — Mon, 05 Aug 2019 13:09:53 GMT

The high accuracy mode will need to use the external HFCLK, which is listed to use at least 250uA when it is on, which means that running in high accuracy mode likely will consume somewhat more current than this.

If you set GPIOTE_CONFIG_IN_SENSE_TOGGLE(false) like Kosmine suggested, your application will use normal mode, and only use the LFCLK, which consumes way less power, and your total current consumption will decrease significantly.

Best regards,

Simon

RE: About current consumption of GPIO and GPIOTE

Simonr — Mon, 05 Aug 2019 13:03:09 GMT

For the nRF52832 the external HF clock is listed at a minimum of 250uA when running (this is the clock that's recommended for high acc. mode). When in high acc. mode you will likely use more current, as 250uA is the minimum drawn by the HFCLK when it's running.

By doing as Kosmine says, and setting GPIOTE_CONFIG_IN_SENSE_TOGGLE(false), you should be able to run this in normal mode, which uses an LF clock instead, consuming way less power (I don't have the exact numbers). Keep in mind that this also will be less accurate.

Best regards,

Simon

RE: About current consumption of GPIO and GPIOTE

takashina hiroki — Mon, 05 Aug 2019 09:49:34 GMT

Please tell me the current consumption of high accuracy mode.

Also, is there any way to provide external interrupt function with low current consumption?
If you have the above method, please tell me the difference from high accuracy mode.

RE: About current consumption of GPIO and GPIOTE

Kosmine — Mon, 05 Aug 2019 06:47:07 GMT

The macro GPIOTE_CONFIG_IN_SENSE_TOGGLE() takes boolean parameter to determine if the event should be run in high accuracy mode. The high accuracy mode by design has more current consumption. Try changing that into GPIOTE_CONFIG_IN_SENSE_TOGGLE(false) and see if that works for you.