Semiconductor integrated circuit device

A semiconductor integrated circuit device comprising:

• a logical circuit comprising a first MIS transistor of a first conductivity type and a second MIS transistor of a second conductivity type, said first and second MIS transistors being formed on a semiconductor substrate;
• a control circuit for controlling a threshold voltage of an MIS transistor included in said logical circuit;
• an oscillation output circuit comprising a third MIS transistor of said first conductivity type and a fourth MIS transistor of said second conductivity type formed on said semiconductor substrate, by which a frequency of an oscillation output can be changed;
• a first switching circuit;
• a second switching circuit;
• and
• wherein a clock signal having a predetermined frequency and an oscillation output of said oscillation output circuit are input to said control circuit,
• said control circuit compares said frequency of said oscillation output with said frequency of said clock signal and generates a first control signal and a second control signal,
• said oscillation output circuit is controlled by said first and second control signals such that said frequency of said oscillation output corresponds to said frequency of said clock signal,
• frequency control of said oscillation circuit is performed by controlling a threshold voltage of said third MIS transistor by said first control signal and by controlling a threshold voltage of said fourth MIS transistor by said second control signal,
• said first control signal is input to said first switching circuit and said first switching circuit outputs a third control signal corresponding to said first control signal,
• said first control signal is input to said second switching circuit and said second switching circuit outputs a fourth control signal based on said first control signal, and
• a threshold voltage of said first MIS transistor is controlled by said third control signal and a threshold voltage of said second MIS transistor is controlled by said fourth control signal.