| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor device with a DVFS technique applied which accurately operates even if a supply voltage is very low.SOLUTION: The semiconductor device includes: a plurality of circuit sections 11A, 11B; a global power supply 25 for supplying a supply voltage VDD; a plurality of power supply circuits for connecting the global power supply to local power supplies 26; and a plurality of local power control circuits for controlling the plurality of power supply circuits such that voltage values of the local power supplies become desired values. Each power supply circuit has a plurality of discrete supply switches 21A-21G. Each local power control circuit has: a voltage monitor circuit 41 having an output whose characteristic value discretely changes with changing voltage value of the local power supply; a storage circuit 42 for storing a target characteristic value of the output of the voltage monitor circuit; a comparator 43 for comparing the characteristic value of the output of the voltage monitor circuit with the target characteristic value; and a switch control circuit 44 for controlling the number of supply switches turned on in accordance with the result of comparison. |
