JPS60119127A - Driving circuit of field effect transistor - Google Patents

Driving circuit of field effect transistor

Info

Publication number
JPS60119127A
JPS60119127A JP58228088A JP22808883A JPS60119127A JP S60119127 A JPS60119127 A JP S60119127A JP 58228088 A JP58228088 A JP 58228088A JP 22808883 A JP22808883 A JP 22808883A JP S60119127 A JPS60119127 A JP S60119127A
Authority
JP
Japan
Prior art keywords
transistor
diode
base
output
capacitor
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.)
Pending
Application number
JP58228088A
Other languages
Japanese (ja)
Inventor
Shuichiro Yamaguchi
周一郎 山口
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Panasonic Electric Works Co Ltd
Original Assignee
Matsushita Electric Works Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Matsushita Electric Works Ltd filed Critical Matsushita Electric Works Ltd
Priority to JP58228088A priority Critical patent/JPS60119127A/en
Publication of JPS60119127A publication Critical patent/JPS60119127A/en
Pending legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H03ELECTRONIC CIRCUITRY
    • H03KPULSE TECHNIQUE
    • H03K17/00Electronic switching or gating, i.e. not by contact-making and –breaking
    • H03K17/04Modifications for accelerating switching
    • HELECTRICITY
    • H03ELECTRONIC CIRCUITRY
    • H03KPULSE TECHNIQUE
    • H03K17/00Electronic switching or gating, i.e. not by contact-making and –breaking
    • H03K17/51Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used
    • H03K17/56Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices
    • H03K17/687Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices the devices being field-effect transistors
    • H03K17/6877Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices the devices being field-effect transistors the control circuit comprising active elements different from those used in the output circuit
    • HELECTRICITY
    • H03ELECTRONIC CIRCUITRY
    • H03KPULSE TECHNIQUE
    • H03K17/00Electronic switching or gating, i.e. not by contact-making and –breaking
    • H03K17/51Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used
    • H03K17/78Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used using opto-electronic devices, i.e. light-emitting and photoelectric devices electrically- or optically-coupled
    • H03K17/785Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used using opto-electronic devices, i.e. light-emitting and photoelectric devices electrically- or optically-coupled controlling field-effect transistor switches

Landscapes

  • Electronic Switches (AREA)

Abstract

PURPOSE:To shorten the OFF time of an output TR by discharging charge applied at the ON of the output TR through an FET connected between the source and draion of the output TR in parallel. CONSTITUTION:A photovoltatic element 1 and a bipolar type TR4 are arranged in parallel between the gate and source of the FET type output TR2, a photovoltatic element 5 is arranged between the cathode of the element 1 and the base of the TR4 and a capacitor 6 is connected to the base of the TR4. The charged capacity of a diode 7, the TR4 and the capacitor 6 is lower than that of the TR2 and their thresholds are lower than that of the TR2. When light is interrupted, the TR2 starts to be discharged and its discharged/charged current flows into the diode 1, but the current flow is interrupted by the element 5, so that the capacitor 5 is discharged and positive voltage is applied to the base of the TR4. Consequently, the charge of the TR2 is discharged through the TR4. The time from the start of the discharge of the TR2 to the ON of the TR4 is shortened on the basis of the relation of said thresholds to the capacity and the charge of the TR2 is immediately discharged mainly through the TR4 in addition to the diode 1.

Description

【発明の詳細な説明】 〔技術分野〕 本発明は光信号金ダイオード・フォトトランジスタ、等
の光起電力素子で電力信号に変換し、その電力信号によ
って電界効果型トランジスタを駆動する電子回路に関す
るものである。
[Detailed Description of the Invention] [Technical Field] The present invention relates to an electronic circuit that converts an optical signal into a power signal using a photovoltaic element such as a gold diode phototransistor, and drives a field effect transistor using the power signal. It is.

〔背景技術〕[Background technology]

光起電力素子を用いた゛1界効果型トランジスタの駆動
回路の一例を第1図に示す。この回路において、光起電
力素子(1)であるダイオード(1)に光が照射される
とダイオード(1)の両端に起電圧が発生し、回路を通
じてMO8型トランジスタ(2)のゲート端子(3)間
の電位差を引きおこす。エンハンスメント型のMOS型
のトランジスタであれば、ゲートに一定以上の電圧がか
かるとこの時出力端子(3)間は導通の状態となる。次
に、光が照射されなくなれば、ダイオード(1)の光起
電力は発生しなくなり、ゲート端子(3)間に蓄積され
ていた電荷はダイオード(1)導通じて放電される。放
電によってゲート電圧が一定以下になると出力端子(3
)間はしゃ断状態となる。
FIG. 1 shows an example of a drive circuit for a field effect transistor using a photovoltaic element. In this circuit, when a diode (1), which is a photovoltaic element (1), is irradiated with light, an electromotive voltage is generated across the diode (1), which passes through the circuit to the gate terminal (3) of an MO8 type transistor (2). ) causes a potential difference between In the case of an enhancement-type MOS transistor, when a voltage above a certain level is applied to the gate, the output terminal (3) becomes conductive. Next, when light is no longer irradiated, the photovoltaic force of the diode (1) is no longer generated, and the charge accumulated between the gate terminals (3) is discharged through the conduction of the diode (1). When the gate voltage drops below a certain level due to discharge, the output terminal (3
) is cut off.

しゃ断状態のとき、光を照射してから導通状態iCなる
までの時間をオン時間と呼び、導電状態から光を消して
しゃ断状態に至るまでの時間をオフ時間と呼ぶ。
In the cutoff state, the time from irradiation with light to the conduction state iC is called the on time, and the time from the conduction state to the turn off of the light to the cutoff state is called the off time.

オン時間はダイオード(1)t−流れる光電流、ゲート
の容量及び第1図には示してないが必要に応じて組込ま
れる回路の抵抗成分等が要因となってきめられる。
The on-time is determined by factors such as the photocurrent flowing through the diode (1), the capacitance of the gate, and the resistance component of a circuit that is incorporated as necessary (not shown in FIG. 1).

オフ時間1寸ゲート端子(3)間の′電圧と、ダイオー
ド(1)の抵抗、その他抵抗成分等が要因となっている
。ところで、良く知られているように、ダイオード(1
)は指数関係的な電流・電圧特性を示(−1一定の電圧
(一般的には0.5〜0.7V)以下では、それ以上の
部分と比べて著しく高抵抗となる。ゲートに蓄積されf
c電荷がダイオード(1)r通じて放電されるとき、ダ
イオード(1)ld前述の高抵抗部分の特性となる。単
純な抵抗コンデンサー回路(RCM路)からも知られて
いるように、抵抗Rが大きいほど時定数が犬きくなり、
オフ時間は長くなる。したがってこの回路では、オフ時
間がオン時間に比べて著しく長いという点が実用上の問
題となっている。
The off time is caused by the voltage across the gate terminal (3), the resistance of the diode (1), and other resistance components. By the way, as is well known, the diode (1
) shows an exponential current-voltage characteristic (-1 Below a certain voltage (generally 0.5 to 0.7 V), the resistance becomes significantly higher than that above it. Accumulation at the gate be f
When the charge c is discharged through the diode (1)r, the diode (1)ld has the characteristics of the high resistance portion described above. As is known from the simple resistance capacitor circuit (RCM circuit), the larger the resistance R, the sharper the time constant.
Off time will be longer. Therefore, this circuit has a practical problem in that the off time is significantly longer than the on time.

オフ時間を短かくするためには第2図のように回路にダ
イオード(1)と並列に抵抗(4)ヲ入れる方法かある
。オフの際は、ダイオード(1)と抵抗(4)の並列抵
抗で放電がおこなわれるため、第1図の回路の場合より
オフ時間が短くなることが期待される。
In order to shorten the off time, there is a method of inserting a resistor (4) in parallel with the diode (1) in the circuit as shown in Figure 2. When the circuit is off, discharge occurs through the parallel resistance of the diode (1) and the resistor (4), so it is expected that the off time will be shorter than in the case of the circuit shown in FIG.

ところがこの回路では、オンのときもこの抵抗(4)を
通じて電流が流れるため、オン時間は長くなる。
However, in this circuit, current flows through this resistor (4) even when the circuit is on, so the on time becomes long.

その上、MO8型トランジスタ(2)のゲートにががる
電圧は、ダイオードの開放電圧よりは低い、抵抵(4)
の両端の電圧となるという欠点がある。
Moreover, the voltage applied to the gate of the MO8 type transistor (2) is lower than the open voltage of the diode, and the voltage applied to the gate of the resistor (4)
The disadvantage is that the voltage is across both ends.

〔発明の目的〕[Purpose of the invention]

そこで、本発明は、光起電力素子を用いた電界効果型の
トランジスタの駆動回路において、オフ時間を短縮する
電界効果型トランジスタの駆動回路全提供すること全目
的とする。
Therefore, an object of the present invention is to provide an entire field-effect transistor drive circuit that shortens the off time in a field-effect transistor drive circuit using a photovoltaic element.

〔発明の開示〕[Disclosure of the invention]

上記目的を達成するために、本発明にかかる電界効果型
のトランジスタの駆動回路は、電界効果型の出力トラン
ジスタ(2)のゲート、ソース間に光起電力素子1) 
’iアノードをゲートに対応させて配置すると1f、に
ベースのしきいち電圧が出力トランジスタ(2)のそn
より低いバイポーラ型のトランジスタ(4)全並列に配
し、光起電力素子(1)のカソードと該トランジスタ(
4)のベース間に光起電力素子(5)を配し、該光起電
力素子(5)とトランジスタ(4)のベース間にコンデ
ンサー(6) e配し、該トランジスタ(4)のベース
とエミッタ間にダイオード(7)ヲカソードをベースに
向けて配して成ることを特徴とする電界効果をのトラン
ジスタの駆動回路である。
In order to achieve the above object, a field effect transistor drive circuit according to the present invention includes a photovoltaic element 1) between the gate and source of a field effect output transistor (2).
'i When the anode is arranged corresponding to the gate, the threshold voltage of the base at 1f is that of the output transistor (2).
A lower bipolar transistor (4) is arranged in parallel, and the cathode of the photovoltaic element (1) and the transistor (4) are arranged in parallel.
A photovoltaic element (5) is arranged between the bases of the transistor (4), and a capacitor (6) is arranged between the photovoltaic element (5) and the base of the transistor (4). This is a field effect transistor drive circuit characterized by having a diode (7) placed between the emitters and a cathode facing the base.

以Fこの発明による電界効果型のトランジスタの駆動回
路ケ第3図及び第4図に示す一実施例に基づ(八て説明
する。
Hereinafter, a driving circuit for a field effect transistor according to the present invention will be explained based on an embodiment shown in FIGS. 3 and 4.

この実施例にお、いてはトランジスタ(4)としてバイ
ポーラ型のトランジスタを用いている。光起電力素子(
1)及びt5)と巳でケまダイオードを使用している。
In this embodiment, a bipolar transistor is used as the transistor (4). Photovoltaic element (
1) and t5) and t5) use diodes.

トランジスタ(4)及びコンデンサ(6)ハ充電さtす
る′電荷のd量が出力トランジスタ(2)のそれに比し
て十分小さいものであると共にそのゲートのしきいチ゛
電圧が出力トランジスタ(2)よりイ氏いものである。
The amount of charge d charged by the transistor (4) and the capacitor (6) is sufficiently smaller than that of the output transistor (2), and the threshold voltage of the gate thereof is lower than that of the output transistor (2). Mr. Lee is ugly.

次にこの電界効果型のトランジスタの駆動回路の動作状
態を説明する。
Next, the operating state of the drive circuit for this field effect transistor will be explained.

ff出力トランジスタ(2)がオンとなる場合を説明す
る。この場合トランジスタ(4)はこの場合の第3図の
等価回路として第4図に示す如くコンデンサー(4g)
、(4h)として働く。
The case where the ff output transistor (2) is turned on will be explained. In this case, the transistor (4) is a capacitor (4g) as shown in Figure 4 as an equivalent circuit of Figure 3 in this case.
, (4h).

光が光起電力素子(1)と(5)に同時に照射されると
こnに光起電力が生じ、出力トランジスタ(2)に正電
圧が加わり該出力トランジスタ(2)はオンする。
When the photovoltaic elements (1) and (5) are simultaneously irradiated with light, a photovoltaic force is generated, a positive voltage is applied to the output transistor (2), and the output transistor (2) is turned on.

一方トランジスタ(4)のベースには光起電力素子(5
)に発生した光起電力により負電圧しか加わらないので
コレクタとエミッタ間はしゃ断されている。
On the other hand, a photovoltaic element (5) is attached to the base of the transistor (4).
) Since only a negative voltage is applied due to the photovoltaic force generated at ), the collector and emitter are cut off.

而してトランジスタ(4)は寄生のコンデンサー(4a
)及び(4b)として働くので光起電力素子(4)の起
電力にエリ出力トランジスタ(2)及びコンデンサー(
4a)はすみやかに充電される。このときコンデンサー
(411)の容量は出力トランジスタ(2)の容量に比
して十分小さくなっていて充電完了速度が早いので、出
力トランジスタ(2)の充電時間はトランジスタ(4)
がない場合とほとんどかわらず、トランジスタ(4)を
用いたためオンとなる動作時間がおそくなることはない
。小容置のコンデンサー(4b)はダイオード(7)と
並列であるので充電されない。
Therefore, the transistor (4) is connected to the parasitic capacitor (4a
) and (4b), so the electromotive force of the photovoltaic element (4) is combined with the output transistor (2) and the capacitor (
4a) is quickly charged. At this time, the capacitance of the capacitor (411) is sufficiently smaller than that of the output transistor (2) and the charging completion speed is fast, so the charging time of the output transistor (2) is shorter than that of the transistor (4).
Since the transistor (4) is used, the turn-on operation time is not slowed down, which is almost the same as when there is no transistor. Since the small capacitor (4b) is connected in parallel with the diode (7), it is not charged.

従って光起電力素子(5)に電流が流れることにより生
ずる電荷はコンデンサー(6) [のみ充電される。
Therefore, the electric charge generated when current flows through the photovoltaic element (5) charges only the capacitor (6).

次に出力トランジスタ(2)がオフとなる場合を説明す
る。この場合出力トランジスタ(2)のみがコンデンサ
ーとして働く。
Next, a case where the output transistor (2) is turned off will be explained. In this case only the output transistor (2) acts as a capacitor.

光をしゃ断するとトランジスタ(2)に貯えられた容量
の放電が始まる。
When the light is cut off, the capacitance stored in the transistor (2) begins to discharge.

トランジスタ(2)の放光電電流はダイオード(1) 
f通じても流れるが、光起電力素子(5)による電流の
流れが止まるので、コンデンサー(6)はただちに放電
し、その放電′亀流はトランジスタ(4)のベースに正
電圧を加える。これによってトランジスタ(4)は導電
状幅となりコンデンサーとしで働く出力トランジスタ(
2)の充電されている電荷はトランジスタ(4)を通じ
て放電でれる。
The discharge current of transistor (2) is the same as that of diode (1).
However, since the current flow through the photovoltaic element (5) is stopped, the capacitor (6) is immediately discharged, and the discharge current applies a positive voltage to the base of the transistor (4). This makes the transistor (4) conductive and the output transistor (4) acts as a capacitor.
The charged charges in 2) are discharged through the transistor (4).

トランジスタ(4)のL4い1直畦圧は出力トランジス
タ(2)のそれより低いので出力トランジスタ(2)が
放電し始めてからトランジスタ(4)がオン状態になる
までの時間はきわめてすみやかであり、この結果出力ト
ランジスタ(2)がオフとなるまでの時間は、出力トラ
ンジスタ(2)に充電されていた電荷がダイオード(1
)のみでなく主としてトランジスタ(4)全通じてすみ
やかに放電されることよりそれだけ短縮されるのである
Since the L4-1 direct voltage of the transistor (4) is lower than that of the output transistor (2), the time from when the output transistor (2) starts discharging until the transistor (4) turns on is extremely quick. As a result, the time it takes for the output transistor (2) to turn off is such that the electric charge stored in the output transistor (2) is transferred to the diode (1).
), but mainly the entire transistor (4) is quickly discharged, which shortens the time by that much.

〔発明の効果〕〔Effect of the invention〕

以上のようにこの発明による電界効果型のトランジスタ
の駆動回路によれば、出力トランジスタをオンさせると
きに充電させる電荷をこの出力トランジスタのソース、
ドレイン間に並列に接続する電界効果型のトランジスタ
を使用して放電することができるので従来の如く光起電
力素子としてのダイオードのみより放電する場合にくら
べてはるかに早く放電させることができ、出力トランジ
スタをオフさせるのが迅速なのである。
As described above, according to the field effect transistor drive circuit according to the present invention, the charge charged when turning on the output transistor is transferred to the source of the output transistor.
Since it is possible to discharge using a field effect transistor connected in parallel between the drains, it is possible to discharge much faster than when discharging only from a diode as a photovoltaic element, as in the past, and the output It is quick to turn off the transistor.

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

第1図及び第2図は各々背景技術を説明する電気回路、
第3図及び第4図はこの発明の一実施例を示す電気回路
である。 特許出願人 松下電工株式会社 代理人弁理士 竹 元 敏 丸 (ほか2名) 第1図 第3図
FIG. 1 and FIG. 2 are electrical circuits explaining the background technology, respectively;
FIGS. 3 and 4 are electrical circuits showing one embodiment of the present invention. Patent applicant Matsushita Electric Works Co., Ltd. Patent attorney Toshimaru Takemoto (and 2 others) Figure 1 Figure 3

Claims (1)

【特許請求の範囲】[Claims] (1)電界効果型の出力トランジスタ(2)のゲート、
ソース間に光起電力素子(1)をアノードをゲートに対
応させて配置すると埃にベースのしきいち電圧が出力ト
ランジスタ(2)のそれより1氏いノくイボーラ型のト
ランジスタ(4)全並列に配し、光起電力素子(1)の
カソードと該トランジスタ(4)のベース間に光起電力
素子(5)を配し、該光起電力素子(5)とトランジス
タ(4)のベース間にコンデンサー(6)ヲ配し、該ト
ランジスタ(4)のベースとエミッタ間にダイオード(
7)ヲカソードをベースに向けて配して成ることを特徴
とする電界効果型のトランジスタの駆動回路。
(1) Gate of field-effect output transistor (2);
If a photovoltaic element (1) is placed between the sources with the anode corresponding to the gate, the threshold voltage of the base will be one degree higher than that of the output transistor (2), and the Ibora type transistor (4) will be fully parallel. A photovoltaic element (5) is arranged between the cathode of the photovoltaic element (1) and the base of the transistor (4), and a photovoltaic element (5) is arranged between the cathode of the photovoltaic element (1) and the base of the transistor (4). A capacitor (6) is placed between the base and emitter of the transistor (4), and a diode (
7) A field-effect transistor drive circuit characterized by having a cathode facing the base.
JP58228088A 1983-11-30 1983-11-30 Driving circuit of field effect transistor Pending JPS60119127A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP58228088A JPS60119127A (en) 1983-11-30 1983-11-30 Driving circuit of field effect transistor

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP58228088A JPS60119127A (en) 1983-11-30 1983-11-30 Driving circuit of field effect transistor

Publications (1)

Publication Number Publication Date
JPS60119127A true JPS60119127A (en) 1985-06-26

Family

ID=16870997

Family Applications (1)

Application Number Title Priority Date Filing Date
JP58228088A Pending JPS60119127A (en) 1983-11-30 1983-11-30 Driving circuit of field effect transistor

Country Status (1)

Country Link
JP (1) JPS60119127A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH01181621A (en) * 1988-01-14 1989-07-19 Mitsubishi Heavy Ind Ltd Clamp mechanism
EP0602708A2 (en) * 1992-12-14 1994-06-22 Koninklijke Philips Electronics N.V. Control electrode disable circuit for power transistor

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH01181621A (en) * 1988-01-14 1989-07-19 Mitsubishi Heavy Ind Ltd Clamp mechanism
EP0602708A2 (en) * 1992-12-14 1994-06-22 Koninklijke Philips Electronics N.V. Control electrode disable circuit for power transistor
EP0602708A3 (en) * 1992-12-14 1995-02-08 Koninkl Philips Electronics Nv Control electrode disable circuit for power transistor.

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