Resistor-capacitor calibration method and resistor-capacitor calibration circuit

A resistor-capacitor (RC) calibration method, applicable to a to-be-calibrated resistor and a to-be-calibrated capacitor, and the RC calibration method comprising:

• providing an RC calibration circuit including:
• a first current source electrically coupled to the to-be-calibrated resistor through a first node;
• a second current source electrically coupled to the to-be-calibrated capacitor through a second node;
• a comparator circuit configured to compare a first voltage of the first node with a second voltage of the second node, and to generate a comparison signal according to a comparison result;
• and
• a processing circuit configured to receive an input clock signal and the comparison signal;
• configuring the processing circuit to perform a calibration process according to a ratio of an input period of the input clock signal to an initial period, wherein the calibration process includes:
• adjusting one or more of a first current of the first current source, a second current of the second current source, and an adjustment magnification of the input period according to the ratio to satisfy an equation for a specified resistance-capacitance product, or adjusting one or more of a resistance and a capacitance in the specified resistance-capacitance product according to the ratio, wherein the initial period is associated with the specified resistance-capacitance product;
• configuring the processing circuit to control the second current source to charge the to-be-calibrated capacitor;
• and
• configuring the processing circuit to determine whether or not the comparison signal indicates that the first voltage and the second voltage meet a calibration completion condition, and if not, adjusting one or more of the to-be-calibrated resistor and the to-be-calibrated capacitor according to the comparison signal, and repeatedly controlling the second current source to charge the to-be-calibrated capacitor until the comparison signal indicates that the first voltage and the second voltage meet the calibration completion condition.