nRF54 PWM support confirmation

[bvyates]

Hello,

We have a custom board we are developing on that uses the nRF54L15 MCU. The board has some LEDs that we were hoping to drive using PWM, but these are connected to pins on port 2, which we have now found do not have PWM support.

Before we respin the board, I just wanted to get an explicit confirmation that PWM cannot work on port 2 pins. This is mentioned in this previous DevZone thread, but it is not explicitly clear, just suggested that this might be the issue. Also the datasheet snip on that thread says ports 1 and 3 can be used, but on the nRF54L15 datasheet I see only port 1 is supported.

Can we get a confirmation that PWM will only work on port 1 pins and that there is no possible to workaround to use pins on port 2?

Thank you

[Kenneth]

Hello,

When in doubt check the datasheet: https://docs.nordicsemi.com/bundle/ps_nrf54L15/page/pwm.html#d1058e1512 Only P1 can be used for PWM.

You may also in general find this useful: https://academy.nordicsemi.com/courses/nrf54l-series-express-course/lessons/lesson-2-power-domains-event-system-and-gpio/topic/gpio-ports-and-pin-planning/ 

Hope that helps,
Kenneth

[noniwalcott]

Hi Kenneth, I am Noni
Are there any recommended alternatives for driving LEDs on P2 pins, such as using timers with GPIOTE, PPI, or a software-based PWM approach, and if so, what are the main limitations in terms of timing accuracy or power consumption on the nRF54L15? Geometry Dash

[Kenneth]

Sorry, I don't see any good way, other than manually bit-bang directly from the application.

Be aware that GPIOTE is not supported on P2, ref: 
https://docs.nordicsemi.com/bundle/ps_nrf54L15/page/gpiote.html#d741e359 

Kenneth