Semiconductor device with delay locked loop

摘要

A semiconductor device capable of easily adjusting an internal delay time is provided with a phase adjusting circuit, wherein the phase adjusting circuit comprises an internal delay reproduction circuit that reproduces the sum of a delay time required for an input signal to be input to the phase adjusting circuit and a delay time required for an output signal to be output from the phase adjusting circuit. A delay adjusting circuit connected with the internal delay reproduction circuit upstream or downstream relative thereto, generates a given delay time for adjusting the internal delay time reproduced by the internal delay reproduction circuit. A delay time control section is connected with the delay adjusting circuit and controls the delay time generated by the delay adjusting circuit. A phase comparator compares a phase of a signal passed through the delay time adjusting circuit with a signal inputted to the phase adjusting circuit. A delay selection circuit generates a given delay time for allowing a phase of the signal passed through the delay adjusting circuit to coincide with a phase of the signal inputted to the phase adjusting circuit, based on an output of the phase comparator.