| 摘要 |
A mobile communication terminal having an RTC(Real Time Clock) frequency compensation circuit is provided to automatically compensate and output an error of a frequency though the error is generated from the frequency outputted from an RTC circuit, therefore reliability and accuracy of time information can be continuously maintained. A crystal oscillator(X1) generates a low frequency clock signal. A frequency counter(110) counts the low-frequency clock signal by setting an inputted VCTCXO(Voltage Controlled Temperature Compensation Crystal Oscillator) to a reference frequency, and outputs an error value if an error is generated. A frequency controller(120) calculates the error value to output a frequency compensation control signal for compensating the error value. A capacitor array(140) selects and outputs a variable combination value of a capacitor for compensating an error frequency according to the frequency compensation control signal. An RTC circuit(130) compensates and outputs a count value of the low-frequency clock signal according to the variable value of the capacitor.
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