Patent ID: 6985026

Claim:
A semiconductor integrated circuit device having a power voltage generation circuit for generating a power voltage, and an internal circuit having an operating speed to which the power voltage is fed from the power voltage generation circuit and which performs specified processing, the semiconductor integrated circuit device further comprising: a first power voltage control circuit which outputs a first control signal for controlling the power voltage of the power voltage generation circuit to maintain the operating speed of the internal circuit within a range, the first power control circuit comprising: a delay evaluation circuit for evaluating a delay amount of the internal circuit; and a first control signal output circuit which, based on an evaluation result of the delay evaluation circuit outputs the first control signal for controlling the power voltage of the power voltage generation circuit so that the power voltage generated by the power voltage generation circuit is raised when the delay amount of the internal circuit becomes larger than an upper-limit value, and the power voltage generated by the power voltage generation circuit is lowered when the delay amount of the internal circuit becomes smaller than a lower-limit value; and a second power voltage control circuit which outputs a second control signal for controlling the power voltage of the power voltage generation circuit so that the power voltage generated by the power voltage generation circuit does not become equal to or higher than a specified voltage.