Patent ID: 7149644

Claim:
A semiconductor integrated circuit comprising: a temperature detector setting a level of a temperature detecting signal to a level indicating a high temperature state when detecting that a chip temperature shifts from low to high and is higher than a first boundary temperature, setting the level of the temperature detecting signal to a level indicating a low temperature state when detecting that the chip temperature shifts from high to low and is lower than a second boundary temperature that is lower compared to the first boundary temperature, and maintains the level of the temperature detecting signal while the chip temperature is between the first boundary temperature and the second boundary temperature; and a control circuit changing its own operating state according to the level of the temperature detecting signal, wherein said temperature detector includes: a temperature detecting unit generating a detection voltage corresponding to the chip temperature; a first differential amplifier comparing a first reference voltage corresponding to the first boundary temperature with the detection voltage; a second differential amplifier comparing a second reference voltage corresponding to the second boundary temperature with the detection voltage; and a flipflop generating the level of the temperature detecting signal according to results of the comparisons from said first and second differential amplifiers.