JPS63191885U - - Google Patents

Description

【図面の簡単な説明】[Brief explanation of drawings]

第１図は本考案によるスイツチング電源の過電
流保護回路の第１実施例を示す電気回路図、第２
図は本考案の第２実施例の電気回路図、第３図は
本考案の第３実施例の電気回路図、第４図は各部
の特性図、第５図は従来の電気回路図、第６図は
従来回路の特性図、第７図は垂下特性図、第８図
はＩＣ内の特性図である。 １……主トランス、２……１次巻線、３……主
開閉素子、４……直流電源、５……２次巻線、１
２……検出増幅回路、１４……電源用ＩＣ、１５
……変流器、２３……時比率制御増幅器、２６…
…全波整流器、２７，２８，３１……抵抗、２９
……コンデンサ、３０……ツエナーダイオード。 Fig. 1 is an electrical circuit diagram showing a first embodiment of the overcurrent protection circuit for a switching power supply according to the present invention;
The figure is an electric circuit diagram of the second embodiment of the present invention, Figure 3 is an electric circuit diagram of the third embodiment of the present invention, Figure 4 is a characteristic diagram of each part, Figure 5 is a conventional electric circuit diagram, FIG. 6 is a characteristic diagram of the conventional circuit, FIG. 7 is a drooping characteristic diagram, and FIG. 8 is a characteristic diagram within the IC. 1... Main transformer, 2... Primary winding, 3... Main switching element, 4... DC power supply, 5... Secondary winding, 1
2...Detection amplifier circuit, 14...Power IC, 15
...Current transformer, 23... Duty ratio control amplifier, 26...
...Full wave rectifier, 27, 28, 31...Resistor, 29
... Capacitor, 30 ... Zener diode.

Claims (1)

【実用新案登録請求の範囲】 (1) 主開閉素子を主体とするチヨツパ回路で直
流電源をチヨツピングし、これを平滑化して直流
出力を得、かつこの直流出力を検出増幅して時比
率制御用ＩＣに入力し、このＩＣの出力にて前記
主開閉素子の開閉の時比率を制御するようにした
スイツチング電源回路において、前記チヨツパ回
路にリアクトルの１次巻線を挿入し、このリアク
トルの２次巻線に全波整流器を介して抵抗を並列
に結合し、この抵抗と並列に、抵抗とコンデンサ
の直列回路を結合し、このコンデンサの出力側を
増幅手段を介して前記ＩＣの時比率制御用端子側
に結合してなることを特徴とするスイツチング電
源の過電流保護回路。 (2) チヨツパ回路は主トランスと１個または複
数個の主開閉素子を直列に接続し、前記主開閉素
子のスイツチングにより主トランスの２次側に交
流電圧を出力するようにしたものからなる実用新
案登録請求の範囲第１項記載のスイツチング電源
の過電流保護回路。 (3) チヨツパ回路は直流電源ラインに主開閉素
子を挿入し、この主開閉素子のスイツチングによ
りパルス電圧を出力するようにしたものからなる
実用新案登録請求の範囲第１項記載のスイツチン
グ電源の過電流保護回路。 (4) 全波整流器はブリツジ接続したものからな
る実用新案登録請求の範囲第１項記載のスイツチ
ング電源の過電流保護回路。[Scope of Claim for Utility Model Registration] (1) Chopping a DC power supply using a chopper circuit mainly consisting of a main switching element, smoothing it to obtain a DC output, and detecting and amplifying this DC output for duty ratio control. In a switching power supply circuit in which input is input to an IC and the output of this IC is used to control the opening/closing time ratio of the main switching element, the primary winding of a reactor is inserted into the chopper circuit, and the secondary winding of this reactor is A resistor is connected in parallel to the winding through a full-wave rectifier, a series circuit of a resistor and a capacitor is connected in parallel with the resistor, and the output side of this capacitor is connected through an amplifying means to control the duty ratio of the IC. An overcurrent protection circuit for a switching power supply characterized by being coupled to the terminal side. (2) A chopper circuit is a practical circuit in which a main transformer and one or more main switching elements are connected in series, and AC voltage is output to the secondary side of the main transformer by switching the main switching element. An overcurrent protection circuit for a switching power supply as claimed in claim 1. (3) The chopper circuit includes a main switching element inserted into a DC power supply line, and a pulse voltage is output by switching the main switching element. Current protection circuit. (4) The overcurrent protection circuit for a switching power supply according to claim 1, wherein the full-wave rectifier is bridge-connected.