| 摘要 |
PURPOSE:To improve an oscillation start characteristic by adding a second feedback gate to a first feedback gate of the CMOS inverter oscillation circuit so as to complement the driving ability of the first feedback gate until the oscillation start controlled by an oscillation detecting circuit and to stop the complement after the oscillation start is detected. CONSTITUTION:An oscillation detecting circuit 101 is provided to detect the stable oscillation of the CMOS inverter oscillation circuit, and a second feedback gate 2 is provided while being connected parallelly with a first feedback gate 1 so as to be operated until the stable oscillation is detected by the oscillation detecting circuit 101 and to stop the operation after the stable oscillation is detected. Since the oscillation start characteristic of the CMOS inverter is correspondent to the driving ability, the CMOS inverter oscillation circuit A is speedily close to the stable oscillating state. When the oscillation detecting circuit 101 detects the stable oscillation, the second feedback gate 2 stops the operation and therefore, the oscillation is continued by the first feedback gate 1 and a feedback resistor Rf afterwards. Thus, since the driving ability is high until the oscillation start, the oscillation start characteristic can be improved. |
