| 摘要 |
PURPOSE:To control easily the time width of a 1-shot circuit for detection of phase difference and also to switch the 1-shot time width through a simple circuit in response to several types of modes, by using an oscillator to a phase difference comparator and also using a frequency dividing circuit. CONSTITUTION:A 1-shot oscillator 6 continues oscillations with a control signal 13. The oscillation cycle of the oscillator 6 is increased by a frequency dividing circuit 7, and a detection circuit 9 measures the oscillation frequency of the oscillator 6. The result of this measurement is supplied to a control circuit 10. The frequency of the oscillator 6 is controlled by a control signal 14. When an input signal 11 is supplied to a reading circuit 4, the oscillator 6 starts its oscillations by an output signal 15 of a voltage controlled oscillator 3 and then stops the oscillations by an output signal 16 of the circuit 7. The various modes are switched by a mode control signal 12, and a mode control circuit 5 controls the circuit 4 and the circuit 7. |
