JPS6298486U

JPS6298486U -

Info

Publication number: JPS6298486U
Application number: JP19059685U
Authority: JP
Priority date: 1985-12-11
Filing date: 1985-12-11
Publication date: 1987-06-23

Description

[Brief explanation of the drawing]

第１図は本考案による一実施例を示す回路図で
ある。第２図は本考案による実施例を示す回路図
である。第３図は第１図および第２図の各部波形
をモデル化して示した参考図である。第４図はフ
ライホイール動作にダイオードを使用した従来の
ＤＣ―ＤＣコンバータの例の回路図である。第５
図はフライホイール動作にＭＯＳＦＥＴを使用し
た従来のＤＣ―ＤＣコンバータの例の回路図であ
る。１……スイツチング回路、２……直流電源、３
……スイツチングトランジスタ、４……制御回路
、５……トランス、６……ダイオード、７……フ
ライホイール動作を掌るＭＯＳＦＥＴ、８……平
滑用チヨーク、９……コンデンサ、１０……負荷
、１１，１４……抵抗、１２……パルス発生回路
、１３……ＭＯＳＦＥＴ、１７……フライホイー
ルダイオード。 FIG. 1 is a circuit diagram showing an embodiment of the present invention. FIG. 2 is a circuit diagram showing an embodiment of the present invention. FIG. 3 is a reference diagram showing a modeled waveform of each part of FIGS. 1 and 2. FIG. 4 is a circuit diagram of an example of a conventional DC-DC converter using a diode for flywheel operation. Fifth
The figure is a circuit diagram of an example of a conventional DC-DC converter using MOSFETs for flywheel operation. 1...Switching circuit, 2...DC power supply, 3
... Switching transistor, 4 ... Control circuit, 5 ... Transformer, 6 ... Diode, 7 ... MOSFET that controls flywheel operation, 8 ... Smoothing choke, 9 ... Capacitor, 10 ... Load, 11, 14...Resistor, 12...Pulse generating circuit, 13...MOSFET, 17...Flywheel diode.

Claims

[Scope of Claim for Utility Model Registration] (1) MO that controls the flywheel operation in the rectifying and smoothing circuit of a DC-DC converter in which the DC power input circuit is switched on and off using a switching transistor.
It has an SFET, a secondary winding provided in an output smoothing coil, and a pulse generation circuit that outputs an output in synchronization with the turn-off of the switching transistor, and controls the flywheel operation during the off period of the switching transistor. MOSFET
The control voltage obtained from the secondary winding of the output smoothing coil is applied to the gate of the MOSFE.
A rectifying and smoothing circuit for a DC-DC converter, characterized in that a circuit for turning on T and a circuit for turning off the MOSFET by the output of the pulse generating circuit when the switching transistor is turned on. (2) A pulse generating circuit having an output synchronized with turn-on of the switching transistor is configured to connect a part of the secondary winding corresponding to the primary winding of the transformer driven by switching the DC power supply by the switching transistor. The rectifying and smoothing circuit for a DC-DC converter according to claim 1, which is a circuit that receives a generated voltage as an input and uses its output to short-circuit the gate and source of the MOSFET. (3) A pulse generation circuit having an output synchronized with turn-on of the switching transistor receives a pulse signal obtained from a control circuit that controls the switching operation of the switching transistor, and uses its output to control the gate and source of the MOSFET. The rectifying and smoothing circuit for a DC-DC converter according to claim 1, which is a circuit for short-circuiting between the DC-DC converters.