Patent ID: 7317341

Claim:
A duty correction device, comprising: a duty correction unit having a plurality of duty correction cells for selectively activating the duty correction cells according to a count signal to thereby adjust a pulse width of an input clock and output an output clock; a phase splitter for generating a rising clock and a falling clock having an opposite phase by splitting a phase of the output clock; a duty cycle corrector (DCC) pumping unit for generating a rising and a falling duty ratio correction signals by performing a pumping operation to the rising and the falling clocks according to a reset signal; a voltage comparing unit for generating a counting increase signal and a counting decrease signal according to a result of comparing the rising and the falling duty ratio correction signals in response to a comparison control signal; a comparison control unit for outputting the comparison control signal to the voltage comparing unit in synchronization with the output clock and for outputting the reset signal to the DCC pumping unit when a duty ratio matching of the input clock and the output clock is completed; and a counter for increasing/decreasing a value of the count signal according to the counting increase and decrease signals, wherein the duty correction cell outputs the output clock by logically combining the input clock and a delayed clock delayed by a RC delay.