Delay control circuit with internal power supply voltage control

A semiconductor device including an internal circuit, said semiconductor device comprising:

• first delay means for delaying an input signal by a first delay time caused by a first delay component on a critical path of said internal circuit by said first delay component with first delay-amount-selecting means included in the first delay means, and, thereby, generating a first delayed signal;
• second delay means for delaying said first delayed signal by a second delay time caused by a second delay component on the critical path of said internal circuit by said second delay component with second delay-amount-selecting means included in the second delay means and, thereby, generating a second delayed signal;
• reference signal generating means, having a delay component identical with delay components of said first delay-amount-selecting means and said second delay-amount-selecting means, for generating a reference signal delayed in phase by one cycle of an internal operating-clock signal in comparison with said input signal;
• phase-difference-detecting means for detecting a phase difference between said reference signal and said second delayed signal;
• and
• power-supply-voltage-adjusting means for adjusting the magnitude of a power-supply voltage supplied to said internal circuit according to said phase difference detected by said phase-difference-detecting means.