Patent ID: 7554415

Claim:
A microcomputer comprising: an oscillator for generating a clock signal having a frequency by using a CR circuit; a multiplier for outputting the clock signal having a multiplied frequency relative to the frequency generated by the oscillator based on data from an external source; a temperature detection unit for detecting temperature at a proximity of the CR circuit; a storage unit for storing data that enables the multiplied frequency of the clock signal in an output from the multiplier to have a constant value based on a temperature-dependent oscillation characteristic of the oscillator; and a control unit for setting a multiplication value for generating the multiplied frequency of the clock signal to the multiplier based on the data in the storage unit that is correlated to the temperature detected by the temperature detection unit, wherein the data in the storage unit is an approximation of an output of the temperature-dependent oscillation characteristic of the oscillator represented by a quadratic curve.