High current problem for app_pwm SDK13.0

[George Leung]

Hi,

I am working on nRF52832 with SDK13.0 + GCC Eclipse.

I have used 2 app_pwm instances for driving a 3 color led. Once I init the pwm and set the duty cycle, the current increase from 3uA (sleep state) to 6.5mA. This 6.5mA current is just for the MCU as I have a separate power supply for the LED, the MCU is sinking current from the LED. When I call app_pwm_disable and app_pwm_uninit, the current still keep at 6.5mA.

Further more, if I just init the pwm but not set the duty cycle, it would be just 1mA and able to go back to 3uA sleep when I disable the pwm.

I have searched for some post about the pwm which mention about the pan73_workaround fix but I already found that in app_pwm_disable.

I have 2 questions: Is 6.5mA normal for using app_pwm? How to remove that 6.5mA when I disable the pwm?

Regards, George

[George Leung]

Hi Sigurd,

I have try that but seem cannot solve the problem. I have try the same code on the nRF52 DK board and I got the same result so I think it is a MCU peripheral problem and not a hardware problem.

Today I have done more test on it. The start and stop of the PWM is function correctly, so I think it is not a while loop problem for polling NRF_ERROR_BUSY. One observation which I think is important, once I call the app_pwm_channel_duty_ticks_set, the current rise to 6.5mA, which is higher than normal MCU full running current (~4.5mA). If I am not calling the app_pwm_channel_duty_ticks_set, all the stuff works fine. Is that some hints which can help?