| 摘要 |
PROBLEM TO BE SOLVED: To improve the accuracy of phase adjustment of a DLL(delay locked loop) circuit and to prevent the generation of jitters by preventing the influence of power source noise generated by the operation of an internal circuit from being transmitted to the DLL circuit. SOLUTION: An external power source to be supplied to this integrated circuit device is divided into first external power sources Vcc1 and Vss1 for the DLL circuit 1 and second external power sources Vcc2 and Vss2 for a circuit other than the DLL circuit. More preferably, the first external power source is utilized for the delay unit part of the variable delay circuit of the DLL circuit and the power source noise generated in the second external power source is prevented from being transmitted to the variable delay circuit. Also, more preferably, the first power source is utilized for a phase matching detection part inside the phase comparator circuit of the DLL circuit (or simply a comparison part) and the power source noise generated in the second external power source is prevented from being transmitted to the phase matching detection part. Also, a first external ground power source is supplied to the variable delay circuit and the phase matching detection part and the influence of the power source noise from a second external ground power source based on the operation of the other circuit is suppressed. |
