3 Replies Latest reply on May 25, 2020 1:47 PM by LePo_1062026

    Low power use of 4200L to generate output frequency


      I have a project where one of the IC need 31.25kHz oscillation to operate.


      Until now I used a crystal on that device and used 4200 micro as my host controller. For low power I put the controller to deep sleep and it was woken up by interrupt from the other device.


      Because the crystal is getting harder to source I wanted to generate the 31.25kHz from the controller. Because 4200 I was using only had 2% accuracy due to RC operation, I changed model to 4200 L and connected 24MHz crystal.


      Using a PWM output to pin, the 31.25Khz signal is generated and the circuit works. However, I need to put the micro into a deep sleep mode to increase battery run time.


      How can I keep the 31.25kHz running while 4200L is deep sleep and also, how can I get it ti wake periodically (every 1 second) to perform some non-interrupt functions that need to be done?