M K

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5 years, 8 months ago.

DEEP SLEEP

Hello, I would like to put the NXP FRDM-K64F into DEEP-SLEEP mode. He should wake up after an hour. Power consumption should be as low as possible. How can I do that? Does anyone have a code example?

Thanks in advance

Question relating to:

Last updated: 27 Aug 2020
The Freedom-K64F is an ultra-low-cost development platform for Kinetis K64, K63, and K24 MCUs.

1 Answer

Martin Kojtal
5 years, 8 months ago.

One hour without wake-up ? You might need to use K64F RTC for that. Look at their SDK, it provides RTC driver.

The app would go to deep sleep if it could (deep sleep is not locked - no hungry power objects are in use like anything that runs on high speed freq clocks). It would wake up when there is next RTOS event and if nothing to do would go to regular sleep or deep sleep - idle loop. Wouldn't this be sufficient for your use case?

That would be the solution to my problem. Unfortunately I can't find any code examples. Do you have a code example for me?

posted by M K 01 Aug 2018

Should work out of the box (if there is nothing to do , app goes to sleep (can be deepsleep if you do not have deepsleep locked), please test it and report back the findings.

posted by Martin Kojtal 01 Aug 2018

I use a LowPowerTicker that wakes up every 30 minutes and changes a variable to perform an action every time the number is even. (the ticker is limited to about 30 minutes). Unfortunately, the microcontroller has a current of 0.12 A in ticker mode, which is very high for DeepSleep. Where could this come from?

posted by M K 01 Aug 2018

what version of mbed OS are you using (SHA or version number) ? . 0.12A sounds to be quite high.

posted by Martin Kojtal 02 Aug 2018

How can I find out and update the version if it is an old one?

posted by M K 02 Aug 2018

https://os.mbed.com/docs/latest/tools/version-control.html

posted by Martin Kojtal 02 Aug 2018

Thanks for the answer. I have updated the version now. This brought me a saving of 10mA. But the power consumption is still very high. Do you have any other ideas what might be the cause?

posted by M K 02 Aug 2018

I would check if your app is going to deep sleep (look at Sleep manager API). If it does not go to deep sleep, something is blocking it. If it goes, then how often and for how long? What is still powered? Any clock domain not being switched off? I recall AnalogIn was one of them for some MCU that even in deep sleep, clock domain would be on and drawing power (just an example).

posted by Martin Kojtal 02 Aug 2018