Why does PWM consume so much power?

[Martijn]

According to the nrf52 product specifications, the PWM peripheral consumes 200 uA running at 16MHz. But a TIMER in combination with PPI an GPIOTE consumes 30.1uA max. Why the big difference?

[Ole Bauck]

The PWM peripheral have more features than using TIMER, PPI and GPIOTE. One of these features is DMA to automatically update the PWM. Therefore the PWM will consume more current. In addition, the Product Specification is an objective Product Specification and the current draw may not be the same as real measured values.

For both peripherals, the high frequency clock (HFCLK) will also be running, so there will be some additional current draw.

[Martijn]

ok, I will wait for the final Product Specification. Is there a way to disable the DMA feature and just use a fixed duty cycle? I know the HFCK is running, but that is for both solutions.

[Ole Bauck]

No, not that I know of. The current PWM driver in the SDK does not use the PWM peripheral, but TIMER+GPIOTE+PPI, so you may save some power using that one.