Title:
CONSTANT VOLTAGE POWER CIRCUIT WITH PROTECTION DEVICE
Document Type and Number:
Japanese Patent JPH04364508
Kind Code:
A
Abstract:
PURPOSE:To offer the constant-voltage power circuit with protection device which can prevent circuit components from breaking when the stabilized power source of dual power source type electronic equipment is used in a wrong power source setting state. CONSTITUTION:The power circuit is equipped with a three-terminal regulator 2 which is applied with a voltage at a point B, divided by resistances R2 and R3 connected to a stabilized output terminal, at an input terminal and compares it with a reference voltage and amplifies their error voltage, a serial control transistor 1 which has its emitter connected to a unstabilized power source side point A and its connector connected to a stabilized output terminal D and also has its base current controlled by the three-terminal regulator 2, and a capacitor C1 for an output terminal, and a Zener diode D1 is connected between the points A and B.
Inventors:
HORIE MITSUO
OSATO KENICHI
HASHIMOTO SHUNICHI
OSATO KENICHI
HASHIMOTO SHUNICHI
Application Number:
JP14001591A
Publication Date:
December 16, 1992
Filing Date:
June 12, 1991
Export Citation:
Assignee:
MATSUSHITA ELECTRIC IND CO LTD
International Classes:
G05F1/56; (IPC1-7): G05F1/56
Attorney, Agent or Firm:
Akira Kobiji (2 outside)