5 independent PWM channels with nRF51 SDK

[pixbroker]

Hello,

I'm new to nRF51 and would like to understand if it is possible to output 5 independent PWM signals to 5 GPIO pins simultaneously on a nRF51?

Thank you.

[Øyvind Karlsen]

Hi,

For the nRF51 you can have a maximum of 4 PWM channels, this is because we have 4 GPIOTE channels.

In theory we could have 8 due to the timers having 4 compare events, however you typically will need one of those compare events to do a reset, so we end up with a theoretical max of 6.

This means that you will have trouble using more than four channels without a GPIO expander on the nRF51.

If you decide to use the nRF52 instead that has three PWM modules which can provide up to 12 PWM channels. This is a hardware PWM, as opposed to the bitbang implementation on the nRF51, this means that it will in most cases perform better.

Best regards,

Øyvind