RV-3049 datasheet(41/65 Pages) MICROCRYSTAL

41 / 65 page

Micro Crystal

DTCXO Temperature Compensated Real Time Clock / Calendar Module

RV-3049

41/65

5.3. METHOD OF COMPENSATING THE FREQUENCY DEVIATION

The Frequency Compensation Unit (FCU) calculates every 32 seconds the compensation factor needed to obtain

accurate time information. The compensation is made by adding or subtracting correction clocks to the 32.768 kHz

reference frequency at the first stage of the frequency divider chain, thereby changing the period of a single

second.

Extra clocks are added for to speed-up the timing, subtracting clocks to slow-down the timing.

If 32.768 kHz Clock too fast: then 32.768kHz clocks are suppressed to obtain a compensated and

accurate RTC timing.

If 32.768 kHz Clock too slow: then extra correction clocks are added to obtain a compensated and

accurate RTC time.

Each compensation period takes 32 seconds. Correction clocks are periodically applied during one complete

compensation period. Within a compensation period of 32 seconds, one correction clock will compensate the time

information by ±1 ppm.

Time compensation cycle 32 seconds: within a time compensation cycle of 32 seconds, the required

numbers of 32.768kHz clocks are periodically suppressed (or added) to compensate the anticipated

deviation of 32.768kHz reference clock.

RV-3049 데이터시트(PDF) 41 Page - MICORO CRYSTAL SWITZERLAND