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For more information about PMIC RTC functionality, please refer to the [https://www.nxp.com/docs/en/data-sheet/MMPF0100.pdf MMPF0100] datasheet.
 
===Powering===
 
Real-time clock is integrated in iMX6 processor. As such, it belongs to SNVS power domain. This domain, in turn, is powered by PMIC, via PMIC_VSNSV rail (see also [[AXEL Lite SOM/AXEL Lite Hardware/Power and Reset/Power Supply Unit (PSU) and recommended power-up sequence|this page]]). PMIC integrates a sort of switch. When 3V3VIN voltage is applied, this is used to power SNVS domain. Otherwise energy is drawn from coin cell battery - if any - connected to PMIC_LICELL (for more details please refer to <ref name="MMPF0100">NXP, ''MMPF0100 - PF0100 Data sheet: Advance Information''</ref>).
 
 
[[File:Axellite-rtc.png|thumb|center|600px|Simplified block diagram of AXEL Lite RTC powering scheme]]
 
 
It is worth remembering that 3.0V lithium batteries are supported and that PMIC_VSNSV voltage range is 2.4 - 3.6V. When [[FAQs_(Axel)#Q:_How_to_enter_RTC_mode.3F|AXEL Lite enters RTC mode]] and 3V3VIN voltage is removed, typical current absorption from PMIC_LICELL pin is about 135uA. This value is '''relatively high''' with respect to the typical lithium coin cell battery capacity (10 - 50mAh). It is recommended that system integrator verify that expected battery lifetime satisfies system requirement. If not, the use of an external low-power RTC device should be considered.
===Pin mapping===
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