topic Re: Inquiries about the use of MCIMX6L3EVN10AB / RTC module in MCX Microcontrollers

Inquiries about the use of MCIMX6L3EVN10AB / RTC module

chung810 — Wed, 12 Feb 2025 11:00:32 GMT

Hello, I'm Chung.
I use MCIMX6L3EVN10AB now.

For save the current consumption, we don't use external crystals(32.768khz)
I want to use "RTC Module" (32.768Khz) through I2C.

How should I handle RTC_XTALI, RTC_XTALO PIN at this time?
GND? Or floating? NC?

Please check. Thank you.

Re: Inquiries about the use of MCIMX6L3EVN10AB / RTC module

JorgeCas — Wed, 12 Feb 2025 18:32:20 GMT

Hello,

RTC_XTALI should be connected to ground.

RTC_XTALO should be left floating.

Best regards.

Re: Inquiries about the use of MCIMX6L3EVN10AB / RTC module

chung810 — Thu, 13 Feb 2025 01:46:46 GMT

Thank you for your reply

I have one more question.
The data sheet says that if It don't use an external crystal as shown below, use a ring oscillator.

"If no external crystal is present, then the ring oscillator is utilized"

As you said, if I set up RTC_XTALI, XTALO PIN, could it crash with the RTC module (36.768Khz) due to ring oscillator operation, causing boot problems or other problems? Or would it have no impact at all?

Re: Inquiries about the use of MCIMX6L3EVN10AB / RTC module

JorgeCas — Thu, 13 Feb 2025 15:57:11 GMT

Hello,

It will not impact the design.

Best regards.