PURPOSE: To attain continuity of stable oscillation even when a NAND circuit and a NOR circuit are used by connecting an oscillation compensation resistor in series with a power supply line.

CONSTITUTION: Input terminals T1, T2 are connected to a NAND gate of an oscillation circuit 1, the gate acts like an inverting circuit and a signal component of a specific frequency of a crystal resonator X in the oscillated output is fed back to the terminal T1(T2) to continue the oscillation. When the phase of a signal feed back to the terminal T1 is deviated and the oscillation output is reduced and the oscillation output level 1 is going to be stopped at a midpoint level, current consumption of the NAND gate is increased. Thus, a voltage drop of an oscillation compensation resistor RC is increased and a voltage applied from a power supply to a power supply terminal VDD is decreased and a threshold level of the T1, T2 is reduced resulting in fluctuating an output signal level. Then the output voltage level is moved forcibly from a midpoint potential to progress the oscillation thereby reducing the current consumption of the NAND gate.