Battery-Backed Time-of-Day clock

davekellogg — Fri, 15 Apr 2011 04:05:48 GMT

Please point me to the schematics that are needed to run the Kinetis when otherwise not powered, as a time-of-day clock. Ie, what parts of the processor need to be powered from a coin battery? Power switching circuits?

Is there an App Note available on implementing a time-of-day clock on Kinetis? If not, it would be a good topic. Hint, Hint. This is going to be a recurring design element for a lot of engineers.

Does MQX have any functionality intended for use with the Real-Time-Clock / Time-of-Day to implement a clock-calendar?

I see that the KwikStik has a 32KHz XTAL. Is that board complete enough to function as a battery-backed time-of-day clock? Is there example code that comes with the board to implement time-of-day functionality?

Thanks!!

Dave.Kellogg

Re: Battery-Backed Time-of-Day clock

UniversalTroope — Fri, 15 Apr 2011 13:13:05 GMT

Go to the Freescale webpage, and do a keyword search for "KQRUG". You will find a Kinetis Peripheral Module Quick Reference. It has an example VBAT circuit diagram. It's really simple, needing just one extra component (plus a battery).

topic Battery-Backed Time-of-Day clock in Kinetis Microcontrollers

Battery-Backed Time-of-Day clock

Re: Battery-Backed Time-of-Day clock