SELF-EXCITED OSCILLATION TYPE HIGH VOLTAGE POWER SOURCE

摘要

PURPOSE:To effectively protect a power source in a simple circuit configuration by composing the base resistance circuit of an oscillating transitor of a Zener diode and a resistor, and operating a protective transistor by the voltage of the connecting point thereof. CONSTITUTION:The base resistance circuit of an oscillating transistor 3 of a self-excited oscillator is composed of the first resistance circuit in which resistors 8, 9 are connected in series, the second resistance circuit in which a Zener diode 11 and a resistor 12 are connected in series, and the third resistance circuit formed of a resistor 13 connected in parallel, and further a Zener diode 15 and a resistor 14 are connected in series with them. When the high voltage is shortcircuited, the voltages at the connecting point of the resistors 8, 9 increases, a protective transistor 10 becomes ON, and the base current of the transistor 3 is reduced.