| 摘要 |
PURPOSE:To enable duty-cycle variable operation in addition to frequency variable operation by setting up a P channel transistor of an open drain and an N channel transistor as ones for a feedback of an oscillatory circuit. CONSTITUTION:The device is provided with the P channel transistor TR11 of the open drain and the N channel TR12 from output terminals. One end of a slide resistor 16 is connected to the drain terminal of the TR11, and the other end is connected to the drain terminal 15 of the TR12, a slide terminal is connected to a terminal 14, and the terminal 14 is connected to GND through a capacitor 9. The resistance value of the resistor 16 shall be R1 between the terminals 13 and 14 and R2 between the terminals 14 and 15 and the capacitance of the capacitor 9 C0. Consequenly, time T1 until a terminal 7 varies to H from L is changed into a function of R1XC0, and time T2 until the terminal varies to L from H is changed into a function of R2XC2. Accordingly, T1 is delayed on R1>R2, and T2 is delayed on R1<R2. An oscillator, frequency thereof is constant and only a duty cycle thereof is varied, can be constituted through said operation. |
