| 摘要 |
A delay locked loop (DLL) for use in a synchronous memory device includes: a first shift controller for generating a first shift-right signal in response to a first comparison signal; a first shift register for performing only a shift-right operation in response to the first shift-right signal; a first delay line unit for controlling each delay amount of internal signals in response to an output of the first shift register, wherein the first delay line unit includes a plurality of delay lines, each delay line having a first unit delay; a second shift controller for generating a second shift-right signal and a shift-left signal in response to a second comparison signal; a second shift register for performing a shift-right operation and a shift-left operation in response to the second shift-right signal and the shift-left signal, respectively; and a second delay line unit for controlling each delay amount of output signals of the first delay line means, wherein the second delay line unit includes a plurality of delay lines, each delay line having a second unit delay smaller than the first unit delay.
|
