i2s capabilities on nrf52840

RE: i2s capabilities on nrf52840

ms360 — Thu, 23 Oct 2025 18:33:51 GMT

I think I would need sign extension to make that work.
Will have to explore other options. thanks .

RE: i2s capabilities on nrf52840

Susheel Nuguru — Thu, 23 Oct 2025 16:32:34 GMT

I am not sure what you mean by 32 bit time slots.

nRF52840 can generate 32 bit time slots for 2 channels. Slot length is set by the BCLK-LRCK RATIO. With stereo it should be something like

slot_bits = RATIO / 2

The I2S peripheral’s SWIDTH supports 8/16/24-bit samples only. You can get 32 bit slots by padding a 24 bit sample to 32 bits. that you can achieve using this

CHANNELS = STEREO
SWIDTH = 24
RATIO = 64 → 32-bit slots

If the TAS2110 requires true 32 bit sample payloads without padding, you cannot do it with nRF52840.

RE: i2s capabilities on nrf52840

ms360 — Thu, 23 Oct 2025 15:02:56 GMT

Thanks Susheel - one more detail -

2 channels on the TAS2110 requires 32 bit time slots.
Is that not possible on nrf52840 ?

RE: i2s capabilities on nrf52840

Susheel Nuguru — Thu, 23 Oct 2025 14:41:21 GMT

The nRF52840 I2S peripheral cannot generate TDM frames beyond stereo. You can only drive a two-channel (left/right) mode of the TAS2110.

This is shown in the CONFIG.CHANNELS register where you can either select stereo (left and right) or , left-only or right-only. This is hard limitation for now. I do not think any of our product have multislot TDM available with I2S, this most likely is to keep to power consumption low while supporting the audio usecase.