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Real time clock (RTC) calculator

What is the real time clock RTC? What is the meaning of the RTC real-time clock?

In embedded systems, RTC provides reliable system time and requires normal operation in the case of system shutdown. The peripheral does not require too many auxiliary circuits. Typically, only a high precision 32.768KHz crystal and resistors and capacitors are required.

error(PPM) Seconds/Day Minute/Year
The frequency error (PPM) produced by the crystal temperature characteristics can be calculated using the formula: -0.042* (25-operating temperature)2Calculation.
  Operating temperature   Crystal frequency error(PPM)   Error (seconds/day)    


The calculator converts the clock precision parts per million (PPM) into real-time accuracy expressed in seconds per day or minutes per year.

Input parameters: PPM, seconds/day or minute/year, click the “Calculate” button to get other calculated values.

The calculator determines the crystal frequency error (PPM) caused by the crystal temperature characteristics; in addition, the equivalent error value in seconds per day is given.