RTC timing system and method

The invention discloses an RTC timing system and method. The system comprises a phase discrimination module used for determining a phase deviation between a low-frequency reference clock and a frequency division clock to be calibrated; the adjusting module is used for adjusting the output clock frequency of the frequency division clock to be calibrated according to the phase deviation to obtain a frequency calibration clock; the frequency division module is used for carrying out frequency division on the frequency calibration clock to obtain a current frequency division calibration clock and feeding back the current frequency division calibration clock to the phase discrimination module to form a closed-loop negative feedback adjustment loop, so that the phase discrimination module carries out frequency division on the low-frequency reference clock according to an error between the current frequency division calibration clock and the low-frequency reference clock; outputting a first target frequency division