Patent attributes
A DLL for reducing jitter during a high frequency operation by separately controlling a coarse delay and a fine delay. The DLL includes a multiplexing unit for selectively outputting one of the rising clock and the falling clock; a first delay line for generating a first internal clock and a second internal clock; a second delay line for generating a first clock and a second clock; a delay line control unit for controlling the second delay line; a phase control unit for generating a first DLL clock and a second DLL clock by mixing the first clock and the second clock; and a phase comparing unit for comparing the first DLL clock and the second DLL clock with the rising clock to generate a lock signal for controlling an operation timing of the first delay line and the second delay line.