nRF52820 PWM

[Mishka]

Hello,

accordingly to the specs I see the nRF52820 has no PWM support for GPIO. Could you confirm please?

Thanks!

[navigator]

Kinda looks that way in terms of a nice peripheral interface.   The OPS v0.7.1 mentions PWM exactly once, in the same cookie cutter language as the other OPS docs (see below).  And then never mentions it again.   

The PPI system allows a TIMER event to trigger a task of any other system peripheral of the device. The PPI system also enables the TIMER task/event features to generate periodic output and PWM signals to any GPIO. The number of input/outputs used at the same time is limited by the number of GPIOTE channels.

You could setup PWM manually I suppose with interrupts, but I'm guessing you like the hardware implementation.

[Mishka]

Yep, every other nRF52 family SoC has at least one 4-channel PWM module with EasyDMA - hence the question.

[haakonsh]

The 52820 and 52811 are stripped-down versions of the nRF52833, neither has the PWM peripheral.

You can create a PWM with the TIMER and GPIOTE peripherals though, see the PWM library.

[Mishka]

Right, the PWM library could do it, but for my project I need it really stable so hardware implementation is more preferred.

I see the nRF52811 has one 4-channel driver and initially I planned to employ it. But the recently released nRF52820 can be powered directly from a lithium battery - this could address a whole bunch of voltage issues for me. By the way, I see the 820 has no SAADC as well, which perhaps means it'll be impossible to monitor battery voltage :-(

[haakonsh]

You can use the COMP peripheral to monitor battery voltage. 

The nRF52833 has some more features than the nRF52820 again.

[Mishka]

Oh, I see, the comp is there. Anyway, I'll probably go with 52811 for now and will keep the 52833 as plan B. Thanks!

BTW, do you by chance know would it be possible to use 52833 in QFN-40 package as drop-in replacement for the 52811?