Hi Team,
I`d like to use the RTC function of OMAP-L138, so here need an independent power supply for RTC_VDD pin. the below picture is from a reference design, if following this solution, what is the type of the battery? if using the 1.5V battery, this voltage seems more than the specification, would you please clarify this question? thanks.
Br,
Shawn Li
Hi Team,
I found some of answers for my question in the ticket:L138 LCDK RTC battery - Processors forum - Processors - TI E2E support forums
I still had several question:
1) if using voltage divider circuit, it will consume some capacity of battery. MT616`s capacity is only 1.05mAh.
2) the holder of the coin battery should be connected with RTC_VSS, not board GND, am I right?
3) can the 1.5V battery be connected with RTC_VDD directly ? what is the meaning of the older design?
Look forward to your answer, thanks.
Hi Rajashri,
Thanks for your reply!
If using BAT54C to combine the VCC_1V3D and the coin battery(3V battery), if there has the power sequence risk for this application when the battery is not presented. this diode will cost some time during OMAP-L138 power-on, the datasheet described RTC_VDD is the first one of the power-on sequence, at least RTC_VDD cannot be after CVDD. would you please help me confirm this question? thanks in advance.
Br,
Shawn Li
