OSCILLATION CONTROL CIRCUIT

PROBLEM TO BE SOLVED: To provide an oscillation control circuit improving a frequency and the starting of the oscillation circuit of a low power voltage operation. SOLUTION: When the oscillation potential of an oscillation signal is between the inversion potential (1.2 volt) of a CMOS inverter IV1 and the inversion potential (1.8 volt) of a CMOS inverter IV2, the logic output value of a CMOS Schmitt inverter SI1 becomes '1'. The output of the CMOS inverter constituted of MOS transistors T32 and T33 is short-circuited through a MOS transistor T34 and the logic output value is kept to be '1'. When the input voltage of the CMOS Schmitt inverter SI1 exceeds the inversion potential of the CMOS inverter IV1 or the inversion potential of the CMOS inverter IV2, becomes higher than the inversion potential (1.8 volt) and the logic output value becomes '0', the CMOS inverter constituted of the MOS transistors T12 and T13 becomes an operation state for the first time. The oscillation signal is inverted and a post stage circuit LA becomes an operation state.