To solve a problem wherein it becomes difficult to keep a power voltage within an operation assurance range due to bounce noise associated with changeover of an operation module in an LSI or rapid current variation in changing an operation frequency, and although it is possible to execute changeover of the operation module and frequency of the LSI based on a voltage measurement result outside of the LSI, it becomes difficult due to influence of a package to correctly measure a voltage.

This semiconductor integrated circuit includes: a measurement means (042) integrated in the semiconductor integrated circuit to measure a maximum voltage or a minimum voltage of a power voltage in a specific time; a measurement result holding means (041) to hold the measurement result thereof; and a reading means to read the measurement result from the measurement result holding means (041). By including such a structure, the variation of a power voltage of an LSI can be kept in an operation assurance voltage range in changeover of an operation module in the semiconductor integrated circuit or in change of the operation frequency, and the LSI can be stably operated.