Patent ID: 7282977
Filing Date: 2007-10-16
Classification: H03K,H03L

Abstract:
1. A duty cycle correction device comprising: a mixer receiving a first clock signal and a second clock signal and mixing phases of the first and second clock signals, thereby outputting a first signal; a phase splitter receiving the first signal and outputting a third clock signal by delaying the first signal for a predetermined period of time and a fourth clock signal by delaying and inverting the first signal for a predetermined period of time; a duty detection unit receiving the third and fourth clock signals and detecting a difference between duty cycles of the third and fourth clock signals; a combination unit for outputting a second signal by combining an output signal of the duty detection unit and previously-stored output signals; a shift register for outputting a first control signal to adjust a mixing ratio of the first and second clock signals, applied to the mixer in response to the second signal; and a phase detection unit receiving the first and second clock signals and outputting a second control signal representing a difference between duty cycles of the first and second clock signals, wherein the mixer adjusts a mixing ratio by using the first and second control signals.