battery back up(RTC) question ???

jkwon · ‎2006-06-05

Posted on June 05, 2006 at 10:50

jkwon · ‎2006-06-04

Posted on June 05, 2006 at 08:53

Dear all~

On the b'rd of STR71x, the power is turned off while the appliation b'rd is working.

And the power of 1.8V from the battery is supplied through V18BK pin(the option is ''STAND-BY Mode Off''). In this case, is it possible to maintain the value of RTC?

I recognized that the RTC Value is maintained based on above condition. Is this result right?

Is there any problem to supply 1.8V Battery Power through V18BK?

I'm looking forward to your sincere advice about my questions.

Thank you~

JK

hichem2 · ‎2006-06-05

Posted on June 05, 2006 at 10:50

Hi,

V18BKP pin is used to provide an external 1.8V supply to the backup block (RTC and Wakeup logic) when bypassing the internal voltage regulator during the STANDBY mode and there is no problem to connect a battery to V18bkp pin.

In other hand,V3.3 should not be removed because the main power supply is mondatory to Keep RTCXTO and RTCXTI pins working properly.

I hope that this can help you,

With best regards,

Hich ;)