| 摘要 |
PURPOSE:To obtain a delay circuit in which a maximum variable delay time is set optionally by providing a waveform shaping circuit having an output stage of open emitter and a comparator circuit comparing the output of waveform shaping circuit with a reference voltage in response to a desired delay time and obtaining an output pulse giving a desired delay time to the front edge or the rear edge to decrease the control voltage. CONSTITUTION:An IC1 is a comparator (or line receiver) whose output stage is open emitter and a constant current circuit CG and a capacitor C are connected to the output terminal. An IC2 is a comparator (or line receiver) with a high input impedance, an output of the comparator IC1 is connected to one input terminal E and a DC reference voltage Vref is applied to the other input terminal F. The constant current circuit CG can be a circuit comprising an operatonal amplifier IC, a transistor Q and a resistor R, the maximum variable delay time is set optionally and the delay time of the front edge and rear edge of an input pulse waveform is set independently. |
