SPI/SPIS power consumption

RE: SPI/SPIS power consumption

Scarlet — Wed, 12 Feb 2014 14:50:34 GMT

Thank you so much! I will think how to reduce the power while using TWI :)

RE: SPI/SPIS power consumption

Håkon Alseth — Wed, 12 Feb 2014 09:53:48 GMT

Hi,

SPI Slave is only active (and requesting 1V2+HFCLK) when CSN is asserted. TWI and SPI master will always request 1V2+HFCLK when it's enabled. You can clear the ENABLE bit in the peripheral to ensure low current consumption.

Best regards Håkon

RE: SPI/SPIS power consumption

Scarlet — Wed, 12 Feb 2014 03:18:43 GMT

Thank you so much!! It really helps!!

For my further application, it may connect with another sensor through TWI.

I want to know the more general conclusion: For SPI/SPIS, TWI (communicate with other devices)

Are these peripherals consume more 1 mA of current only when they are working?

That is, these peripherals would consume very low power when they are sleeping (enabled but idle).

Since I've read the GPIOTE configuration has the power consumption problem. (PAN 2.0, 39, GPIOTE: 1V2 + HFCLK are requested always when the GPIOTE task is configured.) I want to make sure the power consumption problem only happens in GPIOTE.

Thanks agein!

RE: SPI/SPIS power consumption

Håkon Alseth — Mon, 10 Feb 2014 15:17:52 GMT

Hi,

The SPIS only requests the 1V2+HFCLK when CSN is asserted. This means that you can go into sleep with a good conscience :-)

I did a quick test with the "spi_slave_example" in the SDK, and confirmed that it's drawing ~2.3 uA when in sleep (w/ NRF_SPIS1->ENABLE set)

Best regards Håkon