JPH03101180U - - Google Patents
Info
- Publication number
- JPH03101180U JPH03101180U JP856890U JP856890U JPH03101180U JP H03101180 U JPH03101180 U JP H03101180U JP 856890 U JP856890 U JP 856890U JP 856890 U JP856890 U JP 856890U JP H03101180 U JPH03101180 U JP H03101180U
- Authority
- JP
- Japan
- Prior art keywords
- main switch
- transistor
- resistor
- overcurrent protection
- protection circuit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000003990 capacitor Substances 0.000 claims description 3
- 238000001514 detection method Methods 0.000 claims description 3
- 238000006243 chemical reaction Methods 0.000 claims description 2
- 238000004804 winding Methods 0.000 claims 2
- 238000010586 diagram Methods 0.000 description 4
Description
第１図、第２図は従来回路図及びその出力特性
図、第３図、第４図は本考案の一実施例回路図及
びその出力特性図である。図中Ｖ１……入力電源
、Ｖ０……出力電圧、Ｑ１……主スイツチ、Ｔ…
…電圧変換トランス、１……電流検出抵抗、２，
７……トランジスタ、３，４，６……抵抗、５…
…コンデンサである。
1 and 2 are conventional circuit diagrams and their output characteristic diagrams, and FIGS. 3 and 4 are circuit diagrams of an embodiment of the present invention and their output characteristic diagrams. In the figure, V 1 ... input power supply, V 0 ... output voltage, Q 1 ... main switch, T ...
...Voltage conversion transformer, 1...Current detection resistor, 2,
7...Transistor, 3,4,6...Resistor, 5...
...It's a capacitor.
Claims (1)
イツチと、前記トランスの２次巻線側に整流ダイ
オードを介して接続された負荷と、前記主スイツ
チを流れる電流を検出して前記主スイツチを制御
する過電流保護回路を備えたスイツチング電源の
過電流保護回路において、前記過電流保護回路は
主スイツチと直列に接続された電流検出抵抗と、
前記電流検出抵抗の両端に抵抗（第１）を介して
ベース、エミツタが接続されたトランジスタ（第
１）と、前記トランジスタ（第１）のコレクタと
補助電源間に接続された抵抗（第２）とコンデン
サの直列回路と、前記コンデンサの両端にエミツ
タ、ベースが接続されコレクタが抵抗（第３）を
介して前記第１トランジスタのベースに接続され
た第２のトランジスタを備え、前記第１トランジ
スタのコレクタ電位を利用して主スイツチを制御
するようにしたことを特徴とするスイツチング電
源の過電流保護回路。 A main switch connected to the primary winding of a voltage conversion transformer, a load connected to the secondary winding of the transformer via a rectifier diode, and a current flowing through the main switch are detected to activate the main switch. In the overcurrent protection circuit for a switching power supply equipped with an overcurrent protection circuit to control, the overcurrent protection circuit includes a current detection resistor connected in series with the main switch;
A transistor (first) whose base and emitter are connected to both ends of the current detection resistor via a resistor (first), and a resistor (second) connected between the collector of the transistor (first) and an auxiliary power supply. a series circuit of a capacitor and a second transistor having an emitter and a base connected to both ends of the capacitor and a collector connected to the base of the first transistor via a resistor (third); An overcurrent protection circuit for a switching power supply, characterized in that a main switch is controlled using collector potential.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP856890U JP2515394Y2 (en) | 1990-01-31 | 1990-01-31 | Overcurrent protection circuit for switching power supply |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP856890U JP2515394Y2 (en) | 1990-01-31 | 1990-01-31 | Overcurrent protection circuit for switching power supply |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH03101180U true JPH03101180U (en) | 1991-10-22 |
| JP2515394Y2 JP2515394Y2 (en) | 1996-10-30 |
Family
ID=31512194
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP856890U Expired - Fee Related JP2515394Y2 (en) | 1990-01-31 | 1990-01-31 | Overcurrent protection circuit for switching power supply |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2515394Y2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011174712A (en) * | 2010-02-23 | 2011-09-08 | On Semiconductor Trading Ltd | Current detection circuit and semiconductor integrated circuit |
-
1990
- 1990-01-31 JP JP856890U patent/JP2515394Y2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011174712A (en) * | 2010-02-23 | 2011-09-08 | On Semiconductor Trading Ltd | Current detection circuit and semiconductor integrated circuit |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2515394Y2 (en) | 1996-10-30 |
Similar Documents
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |