| 摘要 |
PURPOSE:To reduce the power consumption and to make stable the oscillation, by providing a capacitor of AC coupling between gates of P channel MISFET and N channel MISFET constituting an amplifier circuit. CONSTITUTION:To follow the gate bias of an amplification MISFETQ3 provided at the power supply line A of an oscillating circuit against the variation of the power supply voltage due to the change in the output voltage by a power supply switching circuit 4, a high resistance R4 is provided in parallel with a capacitor C0. When the voltage on the power supply line A is decreased and MISFETQ4 for bias turns off, the resistance R4 forms a discharging path to a coupling capacitor C0. Since the gate voltage of a driving MISFETQ3 follows a voltage change is comparatively short time, it can sufficiently follow the feedback signal fed via the coupling capacitor C0, allowing the oscillation circuit to stably be in oscillation operation. |
