Title:
POWER SOURCE
Document Type and Number:
Japanese Patent JPS59139867
Kind Code:
A
Abstract:
PURPOSE:To simply and effectively prevent the damage of a switching transistor upon shortcircuit defect of the output side of a power source by inserting a constant-voltage element to the base current circuit of the switching transistor. CONSTITUTION:A power source has a DC voltage controller 11 of variable output voltage and a feedback unit 12. The controller 11 has input control means 13 and a DC/DC converter 14. A constant-voltage element such as a Zener diode ZD is provided in the base current circuit of a transistor Tr3 of the converter 14. When the output voltage of the means 13 decreases due to the shorcircuit defect of the power source, the drive current to the transistor Tr3 is interrupted by the constant-voltage element such as a Zener diode ZD, and the transistor Tr3 is turned OFF.
Inventors:
TAKAGI YOSHIO
NAKANO KATSUAKI
NAKANO KATSUAKI
Application Number:
JP1224283A
Publication Date:
August 10, 1984
Filing Date:
January 28, 1983
Export Citation:
Assignee:
TOSHIBA ELECTRIC EQUIP
International Classes:
H02M3/338; H02M3/335; (IPC1-7): H02M3/335
Attorney, Agent or Firm:
Kiyoshi Inomata