VBat on MKL33?

[arnogir]

Hello,

By the past, I develloped a product with K60 and K70 which have internal RTC. Then the microcontroller have Xtal input (32.768KHz) and then a VBat input allowing maintain RTC when power 3V3 is switched off.

Today, I design board with MKL33z256.

there is an internal RTC and RTC_CLKIN (32.768Khz).

But I not find any power input to keep the RTC alive when power is switched Off.

Is something I have not seed? How maintain the RTC over the 3V3 off?

Regards

[PabloAvalos]

Hi @arnogir 

Thank you so much for using our community. i truly appreciate your patience.

Regarding your concern, you should take a look to this thread from our community that it was solved in the past https://community.nxp.com/t5/Kinetis-Microcontrollers/RTC-issue/m-p/724850

Actually, you will need to follow the steps as similar to KL26 board, so hope it helps.

Please let me know if you have more questions.

Thank you again.
Sincerely,
Pablo Avalos.