Phase calibration device and phase calibration method

An phase calibration device, comprising:

• an oscillator for generating a reference clock;
• a phase lock loop coupled to the oscillator for generating an input clock according to the reference clock;
• a multiphase clock generator coupled to the phase lock loop for generating a plurality of output clocks according to the input clock in which the plurality of output clocks have the same frequency but different phases;
• a selector coupled to the multiphase clock generator for selecting one of the plurality of output clocks as an operation clock;
• an analog-to-digital convertor coupled to the selector for generating a conversion result by performing analog-to-digital conversion to input data according to the operation clock;
• a control circuit coupled to the analog-to-digital convertor and the selector for generating and storing at least one parameter according to the conversion result and controlling the selector to do selection;
• and
• a phase calibration circuit coupled to the oscillator, the phase lock loop, the multiphase clock generator and the control circuit for providing a calibration signal for the multiphase clock generator according to the reference clock and a reset signal from the control circuit after turning off and then turning on the phase lock loop, and for receiving the input clock from the phase lock loop to output the input clock to the multiphase clock generator according to the calibration signal, wherein the multiphase clock generator regenerates the plurality of output clocks in accordance with the calibration signal and the input clock while the control circuit controls the selector in light of the at least one parameter to select one of the output clocks as the operation clock.