To furthermore reduce the power consumption of a semiconductor integrated circuit for a real-time clock and to make a generated clock signal available even in peripheral circuits.
The semiconductor integrated circuit includes:a constant voltage circuit which generates a first power supply voltage and a second power supply voltage on the basis of a power supply voltage supplied from the outside; an oscillation circuit to which the second power supply voltage is supplied to generate an original oscillation clock signal by oscillating operation; a frequency division circuit to which the second power supply voltage is supplied to generate a plurality of kinds of frequency-divided clock signals by frequency division of the original oscillation clock signal; a logic circuit to which the first power supply voltage is supplied to manage time count information on the basis of at least one kind of frequency-divided clock signals generated by the frequency division circuit; a selector circuit which selects one of the original oscillation clock signal and the prescribed number of frequency divided clock signals; and an output circuit which supplies the selected clock signal to an output terminal.
KOBAYASHI TAKESHI
Osamu Suzawa
Kazuhiko Miyasaka