Patent attributes
A calibration circuit includes: a differential input circuit, configured to receive first and second oscillation signals, the first and second oscillation signals having the same frequency and opposite phases, duty cycle of the first oscillation signal and duty cycle of the second oscillation signal being in a first preset range, and the differential input circuit being configured to output first and internal signals; a comparison unit, connected to an output end of the differential input circuit and configured to compare duty cycle of the first internal signal and/or duty cycle of the second internal signal; and a logical unit, connected to the comparison unit and the differential input circuit, and configured to control the differential input circuit according to an output result of the comparison unit, such that the duty cycle of the first internal signal and/or the duty cycle of the second internal signal reaches a second preset range.