JPH0795247B2 - DC power supply - Google Patents
DC power supplyInfo
- Publication number
- JPH0795247B2 JPH0795247B2 JP61221865A JP22186586A JPH0795247B2 JP H0795247 B2 JPH0795247 B2 JP H0795247B2 JP 61221865 A JP61221865 A JP 61221865A JP 22186586 A JP22186586 A JP 22186586A JP H0795247 B2 JPH0795247 B2 JP H0795247B2
- Authority
- JP
- Japan
- Prior art keywords
- overcurrent protection
- characteristic
- voltage
- constant current
- 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.)
- Expired - Lifetime
Links
Landscapes
- Continuous-Control Power Sources That Use Transistors (AREA)
- Dc-Dc Converters (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は過電流保護回路を有する直流電源装置に係り、
特に自身の直流電源装置のみならずその負荷回路の保護
にも好適な過電流保護回路を有する直流電源装置に関す
る。The present invention relates to a DC power supply device having an overcurrent protection circuit,
In particular, the present invention relates to a DC power supply device having an overcurrent protection circuit suitable for protecting not only its own DC power supply device but also its load circuit.
〔従来の技術〕 従来の過電流保護回路を有する直流電源装置として、第
４図・第５図のような定電流垂下特性の過電流保護回路
を有する直流電源装置と、第６図・第７図のようなフの
字形特性の過電流保護回路を有する直流電源装置があ
る。[Prior Art] As a DC power supply device having a conventional overcurrent protection circuit, a DC power supply device having an overcurrent protection circuit having a constant current drooping characteristic as shown in FIGS. 4 and 5, and FIG. 6 and FIG. There is a DC power supply device having an overcurrent protection circuit having a fold-back characteristic as shown in the figure.
以下、これらについて説明するが、各図を通じて同一符
号または記号は同一または相当部分を示すものとする。These will be described below, but the same reference numerals or symbols throughout the drawings indicate the same or corresponding portions.
第４図の定電流垂下特性形のものにおいて、１は直流電
源装置の入力電源、２は電源スイッチ、３は制御回路、
４は負荷、５は電流検出用抵抗、６は基準電圧源、７は
誤差増幅器である。制御回路３はシリーズレギュレータ
またはスイッチングレギュレータなどからなり、そのVs
端子は出力電圧検出用端子、Isは過電流信号入力端子で
ある。In the constant current drooping characteristic type of FIG. 4, 1 is an input power source of the DC power supply device, 2 is a power switch, 3 is a control circuit,
Reference numeral 4 is a load, 5 is a current detection resistor, 6 is a reference voltage source, and 7 is an error amplifier. The control circuit 3 is composed of a series regulator or a switching regulator, and its Vs
The terminal is an output voltage detection terminal, and Is is an overcurrent signal input terminal.
第５図は第４図の負荷４両端からみた出力電圧−出力電
流特性図である。第４図の負荷４が過電流状態となり、
電流検出用抵抗５の電圧降下が基準電圧源６の基準電圧
よりも大きくなると、誤差増幅器７により増幅された過
電流信号が過電流信号入力端子Isに入力する。すると制
御回路３が動作して、出力電圧検出端子Vsより検出され
る出力電圧を低下させる。その出力電流値は基準電圧源
６の基準電圧が一定であるために変化せず、第５図のよ
うに定電流垂下特性となる。FIG. 5 is an output voltage-output current characteristic view seen from both ends of the load 4 in FIG. The load 4 in Fig. 4 is in the overcurrent state,
When the voltage drop of the current detection resistor 5 becomes larger than the reference voltage of the reference voltage source 6, the overcurrent signal amplified by the error amplifier 7 is input to the overcurrent signal input terminal Is. Then, the control circuit 3 operates to reduce the output voltage detected by the output voltage detection terminal Vs. The output current value does not change because the reference voltage of the reference voltage source 6 is constant, and has a constant current drooping characteristic as shown in FIG.
第６図のフの字形特性のものにおいて、８・９は分圧用
抵抗である。第７図は第６図の負荷４両端からみた出力
電圧−出力電流特性である。第６図の負荷４が過電流状
態になり、電流検出用抵抗５の電圧降下が出力電圧の分
圧用抵抗８・９による分圧点の電圧よりも大きくなる
と、誤差増幅器７により増幅された過電流信号が過電流
信号入力端子Isに入力する。すると制御回路３が動作し
て、出力電圧検出端子Vsより演出した出力電圧を低下さ
せ、過電流保護機能が働く。出力電圧が低下すると誤差
増幅器７に入力する出力電圧の分圧用抵抗８・９による
分圧電圧も低下する。したがって、電流検出用抵抗５の
電圧降下がより小さな低いレベルの出力電流値で保護さ
れ、第７図のようにフの字形特性となる。In the F-shaped characteristic shown in FIG. 6, 8 and 9 are resistors for voltage division. FIG. 7 is an output voltage-output current characteristic seen from both ends of the load 4 in FIG. When the load 4 in FIG. 6 is in the overcurrent state and the voltage drop of the current detection resistor 5 becomes larger than the voltage at the voltage dividing point of the output voltage dividing resistors 8 and 9, the error amplifier 7 amplifies the excess voltage. The current signal is input to the overcurrent signal input terminal Is. Then, the control circuit 3 operates to lower the output voltage produced from the output voltage detection terminal Vs, and the overcurrent protection function operates. When the output voltage decreases, the divided voltage of the output voltage input to the error amplifier 7 by the voltage dividing resistors 8 and 9 also decreases. Therefore, the voltage drop of the current detection resistor 5 is protected by a smaller and lower level output current value, resulting in a fold-back characteristic as shown in FIG.
第４図・第５図の定電流垂下特性の過電流保護回路を有
する直流電源装置の場合は、電源スイッチ２による電源
投入時にサージ電流が流れる負荷４や容量性をもつ負荷
４、さらには定電流特性をもつ負荷４であっても起動ミ
スが発生しない利点をもつ。しかし、制御回路３の主制
御素子であるパワートランジスタの発熱増大、特にシリ
ーズレギュレータである場合のその発熱増大ならびに増
大した過電流による負荷４およびその配線系統の発熱が
問題となる。In the case of the DC power supply device having the overcurrent protection circuit of the constant current drooping characteristic shown in FIGS. 4 and 5, a load 4 through which a surge current flows when the power is turned on by the power switch 2, a load 4 having a capacitive property, and Even if the load 4 has a current characteristic, it has an advantage that a start error does not occur. However, the heat generation of the power transistor, which is the main control element of the control circuit 3, and the heat generation of the load regulator and its wiring system due to the increased overcurrent, especially in the case of a series regulator, become a problem.
第６図・第７図のフの字形特性のの過電流保護回路を有
する直流電源装置の場合は制御回路３の発熱や負荷４の
発熱の問題はない。しかし、サージ電流が流れる負荷４
や容量性をもつ負荷４、さらには定電流特性をもつ負荷
４であると、同一出力電流値に対して２つの出力電圧を
もつ二値特性のために、起動ミスを発生することがあ
る。In the case of the DC power supply device having the fold-back characteristic overcurrent protection circuit of FIGS. 6 and 7, there is no problem of heat generation of the control circuit 3 or heat generation of the load 4. However, the load 4 through which the surge current flows
In the case of the load 4 having a capacitance, the load 4 having a constant current characteristic, and the load 4 having a constant current characteristic, a start-up error may occur due to the binary characteristic having two output voltages for the same output current value.
本発明の目的は、相反する得失をもつ定電流垂下特性の
過電流保護回路と、フの字形特性の過電流保護回路の各
長所を生かし、以上の各問題点を装置を提供することで
ある。An object of the present invention is to provide a device that solves the above problems by making the best use of the advantages of the constant current drooping characteristic overcurrent protection circuit and the foldback characteristic overcurrent protection circuit. .
本発明装置は定電流垂下特性をもつ過電流保護回路と、
フの字形特性をもつ過電流保護回路を備える。さらに、
電源スイッチ投入にともなう起動時には定電流垂下特性
をもつ過電流保護回路の方が働き起動後にはフの字形特
性をもつ過電流保護回路の方が働くように、両過電流保
護回路を切り換える切換回路を備える。The device of the present invention is an overcurrent protection circuit having a constant current drooping characteristic,
An overcurrent protection circuit having a foldback characteristic is provided. further,
A switching circuit that switches both overcurrent protection circuits so that the overcurrent protection circuit with the constant current drooping characteristic works when the power switch is turned on, and the overcurrent protection circuit with the fold-back characteristic works after the startup. Equipped with.
〔作用〕 本発明においては、電源スイッチ投入時には起動ミスの
ない定電流垂直特性の過電流保護回路が働く。また、起
動時にはフの字形特性の過電流保護回路が働き、制御回
路や負荷等の発熱を抑制する。[Operation] In the present invention, the constant current vertical characteristic overcurrent protection circuit that does not start up when the power switch is turned on operates. Further, at the time of start-up, an overcurrent protection circuit having a fold-back characteristic operates to suppress heat generation of the control circuit and load.
本発明に係る直流電源装置を第１図・第２図を使って説
明する。なお、前記第４図〜第７図の部品符号を適宜に
転用し、重複する説明の一部を割愛する。図中の１は直
流電源装置の入力電源、２は電源スイッチ、３は制御回
路、４は負荷、５は電流検出用抵抗、６は基準電圧源、
７は誤差増幅器、８・９は分圧用抵抗、10は切換回路で
ある。制御回路３はシリーズレギュレータまたはスイッ
チングレギュレータであり、出力電圧検出端子Vsおよび
過電流信号入力端子Isを備える。A DC power supply device according to the present invention will be described with reference to FIGS. Incidentally, the part numbers in FIGS. 4 to 7 are appropriately diverted, and a part of the overlapping description will be omitted. In the figure, 1 is an input power source of the DC power supply device, 2 is a power switch, 3 is a control circuit, 4 is a load, 5 is a resistor for current detection, 6 is a reference voltage source,
7 is an error amplifier, 8 and 9 are resistors for voltage division, and 10 is a switching circuit. The control circuit 3 is a series regulator or a switching regulator, and has an output voltage detection terminal Vs and an overcurrent signal input terminal Is.
第１図および第２図の基準電圧源６は定電流垂下特性の
過電流保護回路の構成要素となる。分圧用抵抗８・９は
フの字形特性の過電流保護回路の構成要素となる。基準
電圧源６の基準電圧、分圧用抵抗８・９の分圧電圧のい
ずれを使うかによって、定電流垂下特性・フの字形特性
のいずれの特性となるかが決まる。The reference voltage source 6 shown in FIGS. 1 and 2 is a component of an overcurrent protection circuit having a constant current drooping characteristic. The voltage dividing resistors 8 and 9 are components of the fold-back type overcurrent protection circuit. Depending on which of the reference voltage of the reference voltage source 6 and the divided voltage of the voltage dividing resistors 8 and 9 is used, which of the constant current drooping characteristic and the fold-back characteristic is obtained is determined.
切換回路10は、電源スイッチ２投入にともなう起動時に
は定電流垂下特性をもつ過電流保護回路が働き、起動後
にフの字形特性をもつ過電流保護回路が働くように、両
過電流保護回路を切り換える。具体的には、基準電圧源
６のと分圧用抵抗８・９の出力回路を切り換える。The switching circuit 10 switches both overcurrent protection circuits so that an overcurrent protection circuit having a constant current drooping characteristic works at the time of starting when the power switch 2 is turned on, and an overcurrent protection circuit having a fold-back characteristic works after starting. . Specifically, the output circuits of the reference voltage source 6 and the voltage dividing resistors 8 and 9 are switched.
第１図の電源スイッチ２を投入してから出力電圧が確立
するまでの起動時には、切換回路10は基準電圧源６の基
準電圧を出力する。基準電圧６は誤差増幅器７に印加さ
れる。この状態で制御回路３が動作して、出力電圧検出
端子Vsより検出される出力電圧は定電流垂下特性で立ち
上る。The switching circuit 10 outputs the reference voltage of the reference voltage source 6 at the time of activation from when the power switch 2 of FIG. 1 is turned on to when the output voltage is established. The reference voltage 6 is applied to the error amplifier 7. In this state, the control circuit 3 operates and the output voltage detected from the output voltage detection terminal Vs rises with a constant current drooping characteristic.
起動所要時間が経過すると、負荷４両端の出力電圧は所
定値以上となる。この段階で、切換回路10は基準電圧源
６の出力を止め分圧抵抗８・９の分圧電圧を出力するよ
うに作動する。その後は分圧用抵抗８・９による分圧電
圧が誤差増幅器７に印加する。この状況下で、負荷４が
過電流状態となり、電流検出用抵抗５の電圧降下が分圧
用抵抗８・９による分圧電圧よりも大きくなると、誤差
増幅器７により増幅れた過電流信号が過電流信号入力端
子Isに入力する。すると制御回路３が動作して、出力電
圧検出端子Vsより検出される出力電圧を低下させフの字
形特性の過電流保護機能が発現する。出力電圧が低下す
ると誤差増幅器７に印加する分圧用抵抗８・９の分圧電
圧も低小さな低い出力電流の値で保護され、第７図のよ
うなフの字形特性となる。When the required start-up time has elapsed, the output voltage across the load 4 becomes a predetermined value or higher. At this stage, the switching circuit 10 operates so as to stop the output of the reference voltage source 6 and output the divided voltage of the voltage dividing resistors 8 and 9. After that, the divided voltage by the voltage dividing resistors 8 and 9 is applied to the error amplifier 7. In this situation, when the load 4 becomes an overcurrent state and the voltage drop of the current detection resistor 5 becomes larger than the divided voltage by the voltage dividing resistors 8 and 9, the overcurrent signal amplified by the error amplifier 7 becomes an overcurrent signal. Input to the signal input terminal Is. Then, the control circuit 3 operates to lower the output voltage detected from the output voltage detection terminal Vs, and the overcurrent protection function having the fold-back characteristic appears. When the output voltage decreases, the divided voltage of the voltage dividing resistors 8 and 9 applied to the error amplifier 7 is also protected by the value of the small, low output current, and the fold-back characteristic shown in FIG. 7 is obtained.
このような動作により、電源スイッチ２の投入時には定
電流垂下特性の過電流保護機能が働いて、起動ミスなく
起動され、出力電圧の安定後はフの字形の過電流保護機
能が働いて直流電源装置自身および負荷４を守る。By such an operation, when the power switch 2 is turned on, the overcurrent protection function of the constant current drooping characteristic works, and it is started without a start-up error, and after the output voltage stabilizes, the foldback overcurrent protection function works and the DC power supply operates. Protect the device itself and load 4.
第２図の細部の構成について補足する。図中の11〜15は
それぞれトランジスタ、16はサイリスタ、17はツエナー
ダイオードであり、これら全体で切換回路10を構成す
る。第１図の電源スイッチ２が投入され、制御回路３が
働き始めると、切換回路10に属するトランジスタ11が当
初はオンしていて、誤差増幅器７の過電流信号入力端子
Isに基準電圧源６の基準電圧が印加される。よって、出
力電圧検出端子Vsで監視される出力電圧は定電流垂下特
性で立ち上る。A supplementary explanation will be given on the detailed structure of FIG. In the figure, 11 to 15 are transistors, 16 is a thyristor, and 17 is a zener diode, which together constitute the switching circuit 10. When the power switch 2 of FIG. 1 is turned on and the control circuit 3 starts to work, the transistor 11 belonging to the switching circuit 10 is initially turned on and the overcurrent signal input terminal of the error amplifier 7 is turned on.
The reference voltage of the reference voltage source 6 is applied to Is. Therefore, the output voltage monitored at the output voltage detection terminal Vs rises with a constant current drooping characteristic.
起動後に第２図のツエナーダイオード17のツエナー電圧
に相当する所定値になると、ツエナーダイオード17がオ
ンし、サイリスタ16がオンし、トランジスタ14・15・12
がオンし、トランジスタ13・11がアフする。このため、
誤差増幅器７の過電流信号入力端子Isに分圧用抵抗８・
９による分圧電圧が印加される。これ以降はフの字形特
性の過電流保護が働く。When the predetermined value corresponding to the zener voltage of the zener diode 17 in FIG. 2 is reached after the start-up, the zener diode 17 turns on and the thyristor 16 turns on, and the transistors 14, 15, 12
Turns on, and the transistors 13 and 11 turn off. For this reason,
The voltage dividing resistor 8 is connected to the overcurrent signal input terminal Is of the error amplifier 7.
The divided voltage by 9 is applied. After that, the fold-back type overcurrent protection works.
以上のような切り換え動作により、起動時には定電流垂
下特性の過電流保護機能が働いて立ち上がり、その後は
切換回路10が作動いてフの字形特性の過電流保護機能が
働く。By the switching operation as described above, the constant current drooping characteristic overcurrent protection function is activated at the time of start-up, and thereafter the switching circuit 10 is activated to operate the foldback characteristic overcurrent protection function.
第３図は他の実施例である。第３図の直流電源装置にお
いて、18は抵抗、19はコンデンサである。これらも、切
換回路10の構成部品となる。起動時には、第２図同様に
定電流垂下特性の過電流保護機能が働く状況下で立ち上
るが、電源スイッチ投入にともなう過渡現象によって抵
抗17とコンデンサ18の時定数でサイリスタ16のゲート電
圧が上昇し、所定時間後にそれが所定値以上になると、
サイリスタ16がオンする。このため、過電流保護機能の
特性がこれを境に定電流垂下特性からフの字形特性にに
切り換わる。FIG. 3 shows another embodiment. In the DC power supply device of FIG. 3, 18 is a resistor and 19 is a capacitor. These are also components of the switching circuit 10. At startup, it starts up under the condition that the overcurrent protection function of the constant current drooping characteristic works as in Fig. 2, but the gate voltage of the thyristor 16 rises due to the time constant of the resistor 17 and the capacitor 18 due to the transient phenomenon caused by turning on the power switch. , If it becomes more than a predetermined value after a predetermined time,
The thyristor 16 turns on. Therefore, the characteristic of the overcurrent protection function switches from the constant current drooping characteristic to the fold-back characteristic at this point.
以上のようにして、電源スイッチ投入から所定時間経過
後にフの字形特性の過電流保護機能に無条件で切り換わ
る。第２図の場合は負荷短絡に近い状態で電源スイッチ
が投入されると、定電流垂下特性のままで推移し、いつ
までたってもフの字形特性に切り換わらないことがある
が、第３図によれば無条件で切り換わるので、負荷短絡
が予想される場合は有利である。As described above, after a lapse of a predetermined time after the power switch is turned on, the overcurrent protection function having the foldback characteristic is unconditionally switched. In the case of Fig. 2, when the power switch is turned on in the state close to the load short circuit, the constant current drooping characteristic is maintained, and it may not switch to the fold-back characteristic forever. Since it switches unconditionally, it is advantageous when a load short circuit is expected.
なお、第２図および第３図のサイリスタ16は定電流垂下
特性からフの字形特性に切り換わった後の状態を電源ス
イッチを再び開放するまで保持する機能を持つ。The thyristor 16 shown in FIGS. 2 and 3 has a function of holding the state after switching from the constant current drooping characteristic to the fold-back characteristic until the power switch is opened again.
本発明においては、当初は定電流垂下特性の過電流保護
機能を働かせた状態で立ち上げ、起動後にフの字形特性
の過電流保護機能に切り換えるので、両特性の長所のみ
があらわれる。このため、起動が確実で、しかも信頼性
および安全性の高い過電流保護機能つきの直流電源装置
が得られる。In the present invention, initially, the overcurrent protection function of the constant current drooping characteristic is activated, and after the start-up, it is switched to the overcurrent protection function of the fold-back characteristic, so only the advantages of both characteristics appear. Therefore, it is possible to obtain the DC power supply device with the overcurrent protection function, which is reliable in starting, and has high reliability and safety.
第１図は本発明による直流電源装置の一実施例を示すブ
ロック図、第２図はその要部回路図、第３図は本発明の
実施例を示す要部回路図、第４図は従来の直流電源装置
を示すブロック図、第５図は第４図装置の出力特性図、
第６図は従来の他の直流電源装置を示すブロック図、第
７図は第６図装置の出力特性図である。 １……入力電源、２……電源スイッチ、３……制御回
路、４……負荷、５……電流検出用抵抗、６……基準電
圧源、７……誤差増幅器、８・９……分圧用抵抗、10…
…切換回路FIG. 1 is a block diagram showing an embodiment of a DC power supply device according to the present invention, FIG. 2 is a circuit diagram of an essential part thereof, FIG. 3 is a circuit diagram of an essential part of the present invention, and FIG. Fig. 5 is a block diagram showing the DC power supply device of Fig. 5, Fig. 5 is an output characteristic diagram of the device,
FIG. 6 is a block diagram showing another conventional DC power supply device, and FIG. 7 is an output characteristic diagram of the device of FIG. 1 ... Input power source, 2 ... Power switch, 3 ... Control circuit, 4 ... Load, 5 ... Current detection resistor, 6 ... Reference voltage source, 7 ... Error amplifier, 8.9 ... minutes Pressure resistance, 10 ...
... Switching circuit
Claims (1)
フの字形特性をもつ過電流保護回路を備え、 さらに、電源スイッチ投入にともなう起動時には上記定
電流垂下特性をもつ過電流保護回路が働き起動後に上記
フの字形特性をもつ過電流保護回路が働くように、前記
両過電流保護回路を切り換える切換回路を備えたことを
特徴とする直流電流装置。1. An overcurrent protection circuit having a constant current drooping characteristic,
Equipped with an overcurrent protection circuit with fold-back characteristics.In addition, when the power switch is turned on, the overcurrent protection circuit with the above-mentioned constant current drooping characteristic works at startup, and after startup, the overcurrent protection circuit with the above-mentioned fold-back characteristics works. As described above, the direct current device is provided with a switching circuit for switching the both overcurrent protection circuits.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61221865A JPH0795247B2 (en) | 1986-09-22 | 1986-09-22 | DC power supply |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61221865A JPH0795247B2 (en) | 1986-09-22 | 1986-09-22 | DC power supply |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6378208A JPS6378208A (en) | 1988-04-08 |
| JPH0795247B2 true JPH0795247B2 (en) | 1995-10-11 |
Family
ID=16773395
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61221865A Expired - Lifetime JPH0795247B2 (en) | 1986-09-22 | 1986-09-22 | DC power supply |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0795247B2 (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2534783B2 (en) * | 1989-11-10 | 1996-09-18 | シャープ株式会社 | Stabilized power supply circuit |
| JP4556116B2 (en) | 2004-11-26 | 2010-10-06 | ソニー株式会社 | Constant voltage power circuit |
| JP4806360B2 (en) * | 2007-01-26 | 2011-11-02 | 日立オートモティブシステムズ株式会社 | Load drive device |
| JP6201775B2 (en) * | 2014-01-16 | 2017-09-27 | 富士通株式会社 | Information processing apparatus, power supply control circuit, and AC adapter |
| CN112771745B (en) | 2018-10-01 | 2023-08-25 | 三菱电机株式会社 | DC power distribution system |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6140623A (en) * | 1984-07-31 | 1986-02-26 | Toko Inc | Dc power supply device |
-
1986
- 1986-09-22 JP JP61221865A patent/JPH0795247B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6378208A (en) | 1988-04-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP0602699A2 (en) | Current limited power semiconductor device | |
| KR880013285A (en) | Integrated circuit protection against overload and short circuit current | |
| US20100165529A1 (en) | Protection circuit apparatus | |
| JPS59136019A (en) | Voltage transient protecting circuit | |
| US6429631B2 (en) | Regulated power source circuit including an overcurrent detecting mechanism for eliminating loss in the output control element | |
| US4945444A (en) | Integratable circuit configuration for reverse current reduction in an inversely operated transistor | |
| JPH0795247B2 (en) | DC power supply | |
| JPH0464209B2 (en) | ||
| US4161759A (en) | Protection circuit for a voltage regulator | |
| US5105145A (en) | Voltage control circuit | |
| JP3033565B2 (en) | Power short circuit protection circuit | |
| NO145901B (en) | TOPOL INCLUDING A TRANSISTOR. | |
| US4445160A (en) | Fault-powered low-level voltage clamp circuit | |
| KR930001681Y1 (en) | Tr protective circuit | |
| JP3587056B2 (en) | Overvoltage protection circuit | |
| SU1166084A1 (en) | Power source with full protection | |
| KR860002286Y1 (en) | Overvoltage protective circuit | |
| JPH0412643B2 (en) | ||
| KR900009468Y1 (en) | Overload protective circuit | |
| SU1068915A1 (en) | D.c.voltage stabilizer | |
| SU1425625A1 (en) | Protected stabilized power swpply source | |
| SU744518A1 (en) | Secondary dc supply source | |
| JP3291877B2 (en) | Power holding circuit | |
| JPS6338694Y2 (en) | ||
| SU1748242A1 (en) | Amplifier-limiter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EXPY | Cancellation because of completion of term |