Device and Method for Measuring a Duty Cycle of a Clock Signal

A duty cycle measurement (DCM) device comprising:

• a clock select circuit configured to provide a first clock signal that has predetermined duty cycle;
• a charge pump circuit configured to receive the first clock signal and to generate a capacitor voltage based on a duty cycle of the first clock signal;
• and
• a clocked comparator circuit configured to receive the capacitor voltage and a reference voltage and to generate a digital output code based on the capacitor voltage and the reference voltage, wherein the digital output code is indicative of the duty cycle of the first clock signal, wherein the charge pump circuit is further configured to receive the digital output code.

A method of determining a duty cycle of a clock signal, the method comprising:

• operating in a calibration mode;
• receiving a first clock signal that has a predetermined duty cycle;
• generating a first capacitor voltage based on the duty cycle of the first clock signal;
• comparing the first capacitor voltage with a reference voltage;
• generating a first digital output code based on the result of the comparison;
• and
• receiving the first digital output code.