Title:
STABILIZED SWITCHING POWER SOURCE CIRCUIT
Document Type and Number:
Japanese Patent JPS5656173
Kind Code:
A
Abstract:
PURPOSE:To prevent damage of a switching element by an output signal from an input voltage detecting means and a pulse width from a pulse width modulation signal becoming higher than predetermined values. CONSTITUTION:A stable DC output is obtained by a pulse signal outputted from a pulse width modulator circuit 10 having a pulse width responsive to the output voltage at an output terminal 7 at normal time under the control of a switching element 4. A pulse signal from the output terminal 10c of the circuit 10 is controlled, when a malfunction such as short-circuit of a load occurs, by a voltage responsive to the input voltage supplied from input voltage detecting means having a detecting circuit 14, a zener diode 15 and a diode 16 to the modulation signal input terminal 10a of the circuit 10, and the pulse width is limited to operate the element 4 within safety operating range. Thus, since the conducting time of the element 4 is controlled in response to the input voltage, the element 4 cannot be broken.
Inventors:
KONNO AKIRA
Application Number:
JP13274979A
Publication Date:
May 18, 1981
Filing Date:
October 15, 1979
Export Citation:
Assignee:
SONY CORP
International Classes:
H02M3/28; H02M3/335; (IPC1-7): H02M3/335