Title:
SWITCHING POWER SUPPLY
Document Type and Number:
Japanese Patent JPS57150012
Kind Code:
A
Abstract:
PURPOSE:To avoid power loss and the generation of heat to ensure an assured starting action, by switching a means that supplies the power supply voltage of a switching control means at the starting time and the steady time after starting. CONSTITUTION:A smoothing capacitor 4 is connected to the output side of a rectifying circuit 3, and a transistor TR5 which is turned on in the starting time is provided at the output side of the capacitor 4. The base of the TR5 is connected to the plus of the output side of the circuit 3 via a resistor 6. At the same time, a collector is connected to the plus of the output side of the circuit 3 with the emitter connected to the collector of a TR8 that forms a differential amplifier along with a TR7. The base of the TR8 is connected to a joint P via a resistor 14 and at the same time to the minus of the output side of the circuit 3 via a constant voltage element, e.g., a Zener diode 15.
Inventors:
KOIZUMI AKIO
SHIRAKAWA MASAMI
SHIRAKAWA MASAMI
Application Number:
JP3433581A
Publication Date:
September 16, 1982
Filing Date:
March 10, 1981
Export Citation:
Assignee:
SONY CORP
International Classes:
H02M3/28; H02M3/335; (IPC1-7): G05F1/64