JPS624736B2

JPS624736B2 -

Info

Publication number: JPS624736B2
Application number: JP5226878A
Authority: JP
Inventors: Fumikazu Hamaya
Original assignee: Nitsuko Corp
Current assignee: NEC Platforms Ltd
Priority date: 1978-05-02
Filing date: 1978-05-02
Publication date: 1987-01-31
Also published as: JPS54144948A; CA1133053A

Description

【発明の詳細な説明】本発明は、中央装置と一対の導体により接続さ
れる端末装置において、中央装置より電力の供給
を受けながら中央装置から送られる直流電圧に影
響されることなく端末装置内負荷に対して定電圧
電源を提供しかつ中央装置に対して定電流信号を
送り返すことができる回路に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention provides a terminal device that is connected to a central device through a pair of conductors, and that is capable of transmitting power within the terminal device while receiving power from the central device without being affected by the DC voltage sent from the central device. It relates to a circuit that can provide a constant voltage power supply to a load and send a constant current signal back to a central unit.

従来の比較的大きい電流を取り出すあるいは流
し込む定電流回路は、定電流回路を制御するため
に外部電源を必要とするとか、あるいはただ一種
類の定電流は造り出せても同一定電流回路を制御
して電流値を変化させるのには機械的接点を必要
とするとか、定電流回路を制御する制御回路電流
を無視できる程度に押さえるのには回路構成が複
雑高価なものになる等の欠点があつた。それ故本
発明の目的は、中央装置に対して定電流入力を持
ち、この電流値を変えることによつて中央装置に
対して電流信号を送ることを可能とし、端末装置
内においては定電圧出力を持つことを安価な簡単
な回路により可能とするためのものである。 Conventional constant current circuits that take out or inject relatively large currents require an external power source to control the constant current circuit, or even if only one type of constant current can be produced, it is difficult to control the same constant current circuit. There are disadvantages such as the need for mechanical contacts to change the current value, and the complicated and expensive circuit configuration needed to suppress the control circuit current that controls the constant current circuit to a negligible level. Ta. Therefore, it is an object of the present invention to have a constant current input to the central device, to make it possible to send a current signal to the central device by changing this current value, and to have a constant voltage output in the terminal device. This is to make it possible to use a simple and inexpensive circuit.

以下、図示を参照して本発明の実施例にもとづ
いて詳細に説明する。 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

第１図は本発明の総合ブロツク図である。第１
図を参照して、Ａは電流はき出し型の定電流回路
であつて、a₁はＡのプラス電源端子で、a₂はＡの
マイナス電源端子で、a₃は電流はき出し出力端子
で、Ａ１，Ａ２，Ａ３はa₃の出力電流を変えるた
めの電流制御用入力端子である。Ｂは電流吸込み
型定電流回路であつて、b₁はＢのプラス電源端子
であり、b₂はＢのマイナス電源端子であり、b₃は
電流吸込み出力端子である。ZD１，ZD２はツエ
ナーダイオードで、それぞれ並列型の定電圧回路
におきかえても良い。ツエナーダイオードZD１
によつて、負荷Ｌへ定電圧が供給される。 FIG. 1 is a general block diagram of the present invention. 1st
Referring to the figure, A is a current output type constant current circuit, _a1 is the positive power supply terminal of A, _a2 is the negative power supply terminal of A, _a3 is the current output terminal, A1, A2 and A3 are current control input terminals for changing the output current of _a3 . B is a current sink type constant current circuit, b ₁ is a positive power terminal of B, b ₂ is a negative power terminal of B, and b ₃ is a current sink output terminal. ZD1 and ZD2 are Zener diodes, and each may be replaced with a parallel type constant voltage circuit. Zener diode ZD1
As a result, a constant voltage is supplied to the load L.

今、Ｉ１より流入した電流をｉ，a₁へ流入する
電流をi₁、ツエナーダイオードZD１に流れる電流
をi₂、負荷すなわちＯ１に流れ込む電流をi₃，a₂
より流れ出る電流をi₄、ツエナーダイオードZD２
に流れる電流をi₅，b₁に流れ込む電流をi₆，Ａの
はき出し電流をｉ_A，Ｂの吸い込み電流をｉ_Bとす
れば、下記の(1)、(2)、(3)、(4)式が成り立つ。 Now, the current flowing from I1 is i, the current flowing into a ₁ is i ₁ , the current flowing to Zener diode ZD1 is i ₂ , and the current flowing into the load, that is, O1 is i ₃ , a ₂
The current flowing out from i ₄ is Zener diode ZD2.
If the current flowing into b is i ₅ , the current flowing into b ₁ is i ₆ , the output current of A is i _A , and the sink current of B is i _B , the following (1), (2), (3), ( 4) The formula holds true.

ｉ＝i₁＋i₂＋i₃ ………(1) i₁＝ｉ_A＋i₄ ………(2) ｉ_A＝i₅＋i₆ ………(3) ｉ_B＝i₂＋i₃＋i₄ ………(4) (1)式へ(2)式を代入すれば、ｉ＝ｉ_A＋i₂＋i₃＋i₄ ………(5) (5)式が得られ、(5)式へ(4)式を代入すれば、ｉ＝ｉ_A＋ｉ_B ………(6) が求められる。(6)式の意味するところは、電流は
き出し型定電流回路Ａのはき出し電流ｉ_Aと、電
流吸込み型定電流回路Ｂの吸込み電流ｉ_Bとを制
御すれば、I₁より流入する電流ｉを制御できるこ
とである。 i=i ₁ +i ₂ +i ₃ ………(1) i ₁ =i _A +i ₄ ………(2) i _A =i ₅ +i ₆ ………(3) i _B =i ₂ +i ₃ +i ₄ … ...(4) By substituting equation (2) into equation (1), i=i _A +i ₂ +i ₃ +i ₄ ......(5) Equation (5) is obtained, and equation (5) is replaced by (4) ), we can obtain i=i _A + i _B (6). Equation (6) means that if the output current i A of the current source type constant current circuit _A and the sink current i B of the current sink type constant current circuit _B are controlled, the current i flowing from I ₁ can be controlled. It's something you can control.

一方、電流はき出し型定電流回路Ａの動作制御
電流はa₂へ流れ、また電流吸込型定電流回路Ｂの
動作制御電流はb₁から入力する。従つて、それぞ
れの動作制御電流はi₄，i₆へ含まれるが、上記(3)
および(4)式から明らかなように、i₄はｉ_Bの一部
であり、i₆はｉ_Aの一部である。従つて、ＢはＡ
に、またＡはＢによつて制御されることになる
が、ｉ_A＞i₆、ｉ_B＞i₄の範囲内では、Ｉ１に流れ
込む電流ｉはＡ，Ｂの制御電流には影響されない
ことになる。 On the other hand, the operation control current of the current source type constant current circuit A flows to _a2 , and the operation control current of the current sink type constant current circuit B is inputted from _b1 . Therefore, the respective operation control currents are included in i ₄ and i ₆ , but the above (3)
As is clear from equation (4), i ₄ is part of i _B and i ₆ is part of i _A. Therefore, B is A
In addition, A will be controlled by B, but within the range of i _A > i ₆ and i _B > i ₄ , the current i flowing into I1 will not be affected by the control currents of A and B. become.

第２図は、第１図におけるＡの具体例を示した
回路である。Ｙ_Aは差動増幅器であつて、このＹ_A
とトランジスタＱ１とによりボルテイジフオロア
を形成しており、非反転入力５には、a₁に対し
て、a₁とa₂との間の電位差を抵抗Ｒ２と抵抗（Ｒ
３＋Ｒ４＋Ｒ５＋Ｒ６）とで分割した電位が与え
られているので、その電位と等しい電位がa₁とＱ
１のエミツタとの間に生ずる。よつてその電位を
抵抗Ｒ１で割つたものがＱ１のコレクタ電流ｉ_A
となる。故にＡ１，Ａ２，Ａ３の任意の一つ、あ
るいは二つ以上をa₂に接続すればｉ_Aの値を変え
ることができる。 FIG. 2 is a circuit showing a specific example of A in FIG. Y _A is a differential amplifier, and this Y _A
and transistor Q1 form a voltage follower, and non-inverting _input 5 is connected _to resistor _R2 and resistor (R
3+R4+R5+R6), so the potential equal to that potential is _a1 and Q
It occurs between the 1. Therefore, the voltage divided by the resistance R1 is the collector current i _A of Q1.
becomes. Therefore, by connecting any one or more of A1, A2, and A3 to _a2 , the value of i _A can be changed.

また第３図は、第１図におけるＢの具体例を示
したものである。Ｙ_Bは差動増幅器であつてこの
Ｙ_BとトランジスタＱ２とによつてボルテイジフ
オロアを形成しており、非反転入力９は、b₂に対
して、b₁とb₂との間の電位差を抵抗Ｒ９とＲ１０
とで分割した電位が与えられているので、その電
位と等しい電位がb₂とＱ２のエミツタ間に生ず
る。よつて、その電位をＲ７で割つたものがＱ２
のコレクタ電流と抵抗Ｒ８に流れる電流との和、
すなわち、b₃より流れ込む電流ｉ_Bとなる。 Further, FIG. 3 shows a specific example of B in FIG. 1. Y _B is a differential amplifier, and this _Y _B and transistor _Q2 form _a voltage follower. The potential difference between resistors R9 and R10
Since a potential divided by Q2 is given, a potential equal to that potential is generated between _b2 and the emitter of Q2. Therefore, the potential divided by R7 is Q2
The sum of the collector current of and the current flowing through resistor R8,
In other words, the current i _B flows from b ₃ .

抵抗Ｒ８が挿入されているのは第１図のＡの制
御電流はＢによつて制御され、第１図のＢの制御
電流はＡによつて制御されているので、抵抗Ｒ８
がなければ、端子I₁とI₂間に、電圧を印加して
も、第２図中の差動増幅器Ｙ_Aおよび第３図中の
差動増幅器Ｙ_Bに電力が供給されないので、第１
図に示される回路は動作しないことになるためで
ある。すなわち、Ｒ８によつてＹ_Aに、まず起動
のための電流を与え、その結果a₃より電流が流れ
出し、Ｙ_Bに電力が与えられることになり、Ｙ_Bが
動作をはじめることになる。その結果Ｙ_Aにさら
に大きな電力が供給される。Ｙ_AとＹ_Bにはこのよ
うにして、a₃より流れる電流およびb₃より流れ込
む電流を十分制御できる電力が与えられ、第１図
に示す定電流回路が動作することになる。 The reason why the resistor R8 is inserted is because the control current of A in FIG. 1 is controlled by B, and the control current of B in FIG. 1 is controlled by A.
Without it, even if a voltage is applied between terminals _I1 and _I2 , power will not be supplied to differential amplifier _YA in FIG. 2 and differential amplifier _YB in FIG.
This is because the circuit shown in the figure will not operate. That is, a current for starting is first applied to YA through _R8 , and as a result, current flows from _a3 , power is applied to _YB , and _YB starts operating. As a result, even more power is supplied to _YA . In this way, Y _A and Y _B are given power that can sufficiently control the current flowing from a ₃ and the current flowing from b ₃ , and the constant current circuit shown in FIG. 1 operates.

また端子Ｉ１，Ｉ２間に与えられる電圧が変動
したとしても、その変動分は、トランジスタＱ１
およびＱ２のエミツタ、コレクタ間に分配される
ので、端末装置への供給電圧の変動によつて定電
流回路が影響を受け中央装置へ送出する電流量が
変化することはない。 Furthermore, even if the voltage applied between terminals I1 and I2 fluctuates, the amount of the fluctuation is
Since the current is distributed between the emitter and collector of Q2, the constant current circuit is not affected by fluctuations in the voltage supplied to the terminal equipment, and the amount of current sent to the central equipment does not change.

以上本発明の一実施例に関して詳細に説明した
が、本発明を種々に変形することは可能である。
たとえば、第１図のI₁，I₂の極性を全く逆にす
る、第２図中の抵抗Ｒ３，Ｒ４，Ｒ５，Ｒ６の代
りに可変抵抗器に置き換え制御電流を連続に変え
ることを可能にする。第３図中の抵抗Ｒ８を取り
除き第２図中のトランジスタＱ１のエミツタ、コ
レクタ間に抵抗を追加する等は可能である。 Although one embodiment of the present invention has been described in detail above, it is possible to modify the present invention in various ways.
For example, the polarity of I ₁ and I ₂ in Figure 1 can be completely reversed, or the resistors R3, R4, R5, and R6 in Figure 2 can be replaced with variable resistors, making it possible to continuously change the control current. do. It is possible to remove the resistor R8 in FIG. 3 and add a resistor between the emitter and collector of the transistor Q1 in FIG. 2.

[Brief explanation of the drawing]

第１図は、本発明の一実施例を示すブロツク
図、第２図は、第１図中のＡの一具体例を示す回
路図、第３図は第１図中のＢの一具体例を示す回
路図である。Ｉ１，Ｉ２……電力受取り用端子、Ｏ１，Ｏ２
……負荷接続用端子、Ａ１，Ａ２，Ａ３……電流
制御用端子、Ａ……電流はき出し型定電流回路、
Ｂ……電流吸込型定電流回路、ZD１，ZD２……
ツエナーダイオード、Ｙ_A，Ｙ_B……差動増幅器。 FIG. 1 is a block diagram showing one embodiment of the present invention, FIG. 2 is a circuit diagram showing a specific example of A in FIG. 1, and FIG. 3 is a specific example of B in FIG. FIG. I1, I2...Power receiving terminal, O1, O2
...Load connection terminals, A1, A2, A3...Current control terminals, A...Current output type constant current circuit,
B...Current sink type constant current circuit, ZD1, ZD2...
Zener diode, Y _A , Y _B ... Differential amplifier.

Claims

[Claims]

1. First and second terminals I ₁ and I ₂ for power reception, first and second terminals O ₁ and O ₂ for load connection, n current control terminals A ₁ , A ₂ ...... , A _o
In the terminal device, the positive power terminal is connected to the first power receiving terminal _I1 and the first
A current output type constant current circuit is connected in common to the terminal _O1 of the circuit, the negative power supply terminal is connected to the second terminal for connecting the load, and the input terminal for current control is connected to the terminal for current control, respectively, and the positive The power supply terminal is connected to the current output terminal of the current output type constant current circuit, the negative power terminal is connected to the second terminal _I2 for receiving power, and the current sink terminal is connected to the negative power supply terminal of the current output type constant current circuit. and the first and second terminals O ₁ and O ₂ for connecting the load.
and a second constant voltage circuit connected between the current output terminal of the current output type constant current circuit and the second terminal for receiving power, The above current control terminal A ₁ ,...
..., when a predetermined control voltage based on the plus and minus power terminals of the current drawing type constant current circuit is applied to a predetermined terminal of A _o , the power is supplied from the first and second terminals for receiving power. The current flowing in from the first terminal _I1 for receiving power and the current flowing out from the second terminal _I2 can be controlled according to the applied control voltage without being affected by fluctuations in the applied voltage, On the other hand, the first
and a constant current circuit configured to provide a constant voltage between the second terminal.