nRF52840 I2S consumption

[perove]

What is the most energy efficient microphone input method, PCM via I2S or PDM. Does the SoC have a special HW handling of the PDM format for converting to PCM? Does the filtering of the 1 bit conversion compete with other processes on the SoC for resources (i.e. would one be better off with a built in conversion in the mic).

[Ole Bauck]

Hi,

The I2S current consumption is not specified in the product specification, but is about the same as PDM.

The PDM has hardware decimation filters to convert the incoming data stream into PCM audio samples, see here. This does not compete with other processes on the SoC.

I would use PDM over I2S as the I2S on nRF52 has some erratas, see here.

Ole

[Ole Bauck]

Also see this post: devzone.nordicsemi.com/.../