JPS649426U

JPS649426U -

Info

Publication number: JPS649426U
Application number: JP10209487U
Authority: JP
Priority date: 1987-07-02
Filing date: 1987-07-02
Publication date: 1989-01-19
Anticipated expiration: 2002-07-02
Also published as: JPH0534197Y2

Description

[Brief explanation of the drawing]

第１図は本考案による充電回路の一実施例を示
す図、第２図は上記実施例の一連の動作の中での
サイリスタのゲード電流とアノード電流との関係
の変化サイクルを示す図、第３図は上記一変化サ
イクルにおける回路上の各点の電圧及び電流の変
化を示す図、第４図及び第５図は夫々一従来例及
び他の従来例の回路を示す図である。１……主コンデンサ、２……ストロボ管、３…
…トリガ回路、４……交流電源、５……電源スイ
ツチ、７……トランス、８……整流器、９……充
電電流制限抵抗、１０，１１……分圧抵抗、３１
……ＭＯＳＦＥＴ、３２，３３……ダイオード、
３４……プルアツプ抵抗、３５，４０……抵抗、
３６，３８……定電圧ダイオード、３７……サイ
リスタ、３９……コンデンサ、４１……充電電圧
制御回路。 FIG. 1 is a diagram showing an embodiment of the charging circuit according to the present invention, FIG. FIG. 3 is a diagram showing changes in voltage and current at each point on the circuit in one change cycle, and FIGS. 4 and 5 are diagrams showing circuits of one conventional example and another conventional example, respectively. 1... Main capacitor, 2... Strobe tube, 3...
... Trigger circuit, 4 ... AC power supply, 5 ... Power switch, 7 ... Transformer, 8 ... Rectifier, 9 ... Charging current limiting resistor, 10, 11 ... Voltage dividing resistor, 31
...MOSFET, 32,33...diode,
34...Pull-up resistor, 35,40...Resistor,
36, 38... Constant voltage diode, 37... Thyristor, 39... Capacitor, 41... Charging voltage control circuit.

Claims

[Claims for Utility Model Registration] An AC power source, a rectifier circuit that converts the AC power source to DC, a main capacitor charged by the rectifier circuit, and a charging current limiter that limits the value of current flowing into the main capacitor. A charging circuit comprising a resistor and a charging voltage control circuit located between the rectifier circuit and the main capacitor and controlling the charging voltage of the main capacitor, wherein the charging voltage control circuit has a drain terminal connected to the charging current limiting resistor. a MOSFET whose source terminal is connected to the positive output of the rectifier circuit via a pull-up resistor, whose source terminal is connected to the positive electrode of the main capacitor, and whose gate terminal is connected to the positive output of the rectifier circuit via a pull-up resistor; a charging voltage voltage divider circuit connected between both poles of the MOSFET, an anode terminal connected to the gate terminal of the MOSFET, a cathode terminal grounded via a constant voltage diode facing the opposite voltage direction, and a gate terminal connected to the charging voltage It is connected to the voltage dividing point of the voltage dividing circuit, and the anode current at turn-on is the MOSFET.
and a thyristor whose current is limited to a holding current or less by a pull-up resistor of the ET, and when the voltage at the voltage dividing point of the charging piezoelectric voltage divider circuit exceeds the reverse voltage of the constant voltage diode, the thyristor turns on and the When the charging of the main capacitor is stopped by lowering the gate voltage of the MOSFET and putting the MOSFET into a high resistance state, and the voltage at the voltage dividing point of the charging voltage voltage dividing circuit becomes equal to or lower than the reverse voltage of the voltage regulator diode. . A charging circuit characterized in that the main capacitor is charged by turning off the thyristor and increasing the gate voltage of the MOSFET to make the MOSFET conductive.