SPI CURRENT??

[Sudipta Banerjee]

Hi, Actually in our application we have connect accelerometer sensor to Nordic by SPI. I'm calculating power consumption for it. In datasheet it's mentioned for SPI Data communication @ 8Mpbs current will be 200uA. Now my question is if we send only 50Kb data in a whole day with that speed, then what will be the current?? It'll be like we have to multiply sending time for the data & current, or anything else. Just let me know how we are going to calculate currents for it.

Regards, Sudipta

[Marc Nicholas]

Are you switching off the SPI peripheral blocks in between communication? If so, your statement is correct. If not, it's not :)

-m

[Ole Morten]

I'd recommend you to take a look on this question.

As you can understand from it, the SPI current will be drawn only when the SPI module is active and is actually transmitting data. In between transfers, when the SPI module is off (i.e. most of the day in your scenario), the current draw of it will be 0, and the draw of the complete chip will be dependent on the sleep mode you're in.