RTC clock frequency

Ashutosh Nahar

Intellectual 640 points

HI,

I ask doing RTC circuit designing and Wondering why we always have Crystal with 32.768kHz only?

Why we cannot select any other frequency crytal?

Thanks

Ashutosh

over 9 years ago

0 Timothy T over 9 years ago

TI__Mastermind 28590 points

32.768 kHz is the common frequency for RTC applications because a 15 bit divider divides by 32768. (2^15 = 32768). With this divide, a 1 Hz signal is generated for incrementing a "second" counter.

73,
Timothy

Clock & timing

Clock & timing forum

RTC clock frequency