Direct current to direct current converting type power source device

Abstract

Abstract PURPOSE:To enable the use of elements, which need not have allowance to a rated value, by a method wherein an overcurrent detecting circuit is formed which compares voltage corresponding to currents at the primary side of a transformer and a DC voltage level being proportional to output voltage. CONSTITUTION:Output from an oscillation circuit OSC controls a main switching element ST through a pulse width control circuit I and a driver circuit II, an output voltage is generated at the secondary side of the transformer TR while the pulse width control circuit I is controlled by output from an output voltage detecting circuit IV, and output voltage is stabilized. Output from the output voltage detecting circuit IV and currents at the primary side of the transformer TR are provided to a comparator COM2 of the overcurrent detecting circuit III to control the driver circuit II. Thus, since currents can instantaneously be reduced when the output from the OSC becomes to overload and the currents exceed a rated value, the elements having no allowance are used, and reliability can be maintained.

Inventors

• 👤 Yoichi Ueki
• 👤 Toshifumi Washio

Bibliographic Details