Title:
POWER SOURCE
Document Type and Number:
Japanese Patent JPS58172975
Kind Code:
A
Abstract:
PURPOSE:To prevent power source circuit from stopping by reenergization by constructing not to operate a protecting circuit even if the reenergization takes place immediately after an AC input power source circuit is interrupted. CONSTITUTION:A series circuit of a constant-voltage diode 41 and a resistor 42 is inserted and connected between the crossing point of a resistor 40 and diodes 2, 4 and the cathode of a constant-voltage diode 19, and a diode 43 is inserted and connected with the terminal side as a cathode. When a power switch is reenergized until charge of a condenser 20 is discharged by interupting the power switch, a voltage higher than 10 times of the normally operating time is generated across the resistor 40. As a result, the diodes 41, 43 are conducted, and the charge of the condenser 20 is discharged. Since the diode 41 is interrupted after the condenser 20 is discharged up, no overcurrent is flowed through an output transistor 10.
Inventors:
TAKESHITA MASAHIRO
Application Number:
JP5503182A
Publication Date:
October 11, 1983
Filing Date:
April 01, 1982
Export Citation:
Assignee:
MATSUSHITA ELECTRIC IND CO LTD
International Classes:
H02M3/28; H02M3/335; (IPC1-7): H02M3/335
Attorney, Agent or Firm:
Shigetaka Awano (1 person outside)
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