Minimal Vbat voltage to keep RTC time on MK64/66 MCUs?

[Anonymous]

Hi, there is MK64 datasheet table "VBAT power operating requirements" which seems to imply the answer to my question but the meaning of the variable shown there is not obvious and there is no description of that spec. What is "VPOR_VBAT -> Falling VBAT supply POR detect voltage" ? How does it relate to the table's title "VBAT power operating requirements" ?

Will RTC clock be maintained when powering down the main power Vdd and keeping a button battery voltage ~1.5 V on Vbat?

[jorge_a_vazquez · Accepted solution]

Hi Vladimir Blanshey''

No, Actually this specification describes the voltages when the modules under VBAT domain will detect reset state. this is, below 1.5V, RTC and VBAT Register File will lose its registers values.

VBAT_POR will assert if VBAT is below 1.50V, but if you want to assure the correct function of the RTC, you have to keep VBAT in the range specified in the "Voltage and current operating requirements"

Hope this helps

Best regards