JPS615669A - Constant current feeding circuit of subscriber circuit - Google Patents
Constant current feeding circuit of subscriber circuitInfo
- Publication number
- JPS615669A JPS615669A JP59120666A JP12066684A JPS615669A JP S615669 A JPS615669 A JP S615669A JP 59120666 A JP59120666 A JP 59120666A JP 12066684 A JP12066684 A JP 12066684A JP S615669 A JPS615669 A JP S615669A
- Authority
- JP
- Japan
- Prior art keywords
- voltage
- amplifier
- inverting input
- constant current
- hook
- 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
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M19/00—Current supply arrangements for telephone systems
- H04M19/001—Current supply source at the exchanger providing current to substations
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
- Y02D30/00—Reducing energy consumption in communication networks
- Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks
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- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Devices For Supply Of Signal Current (AREA)
Abstract
Description
【発明の詳細な説明】
発明の技術分野
本発明はディジタル交換機の加入者回路の定電流給電回
路に関するものであシ、さらに詳しく言えば、オンフッ
ク時の電力消費を低減させ得る定電流給電回路に関する
。TECHNICAL FIELD OF THE INVENTION The present invention relates to a constant current power supply circuit for a subscriber circuit of a digital exchange, and more particularly, to a constant current power supply circuit capable of reducing power consumption during on-hook. .
技術の背景
局から加入者電話機までの距離に依存せず一定の電流を
供給し得るようにした加入者回路の定電流給電回路はす
でに知られている。このような定電流給電回路は加入者
電話機毎に設けられているが、常時作動しておシ、電話
機を使用していないいわゆるオンフック時もオフフック
時と同等の電力消費が生ずるようになっておシ、オンフ
ック時の節電が要望されている。・
従来技術と問題点
第１図に従来の定電流給電回路を示す。第１図回路にお
いて、通話路Ｂと地気（接地）Ｇとの間、通話路ムと電
源ｖ０との間に設けら扛た回路は対称的に接続さｎてい
る。通話路ＡとＢとの間の抵抗器Ｒ１ｇとＲ１によシ、
今Ｒ，，−Ｒ１とじて、通話路ＡＢＯ線間電圧の中点電
圧が検出される。この電圧を増幅器Ａａを介した電圧を
ｖＡとする。一方電源ｖＩＩＢと地気０間の電圧ＶＢは
抵抗器Ｒ工、。BACKGROUND OF THE INVENTION Constant current supply circuits for subscriber circuits are already known which are capable of supplying a constant current independent of the distance from the station to the subscriber telephone. Although such a constant current power supply circuit is provided for each subscriber telephone, it is always in operation, and even when the telephone is not in use, so-called on-hook, it consumes the same amount of power as when it is off-hook. There is a demand for power saving when on-hook.・Prior art and problems Figure 1 shows a conventional constant current power supply circuit. In the circuit of FIG. 1, the circuits provided between the communication path B and the earth (ground) G and between the communication path M and the power source v0 are connected symmetrically. Due to the resistors R1g and R1 between communication paths A and B,
Now, the midpoint voltage of the line voltage of the communication path ABO is detected from R, , -R1. This voltage is expressed as vA through the amplifier Aa. On the other hand, the voltage VB between the power supply vIIB and the ground zero is resistor R.
Ｒ１，、Ｒ１，ｔ Ｒ，、によ多分割され、増幅器Ａ１
の非反転入力の電圧ｖ８、増幅器Ａ３の非反転入力の電
圧Ｖ、が得られる。R1,, R1,t R, , is divided into multiple parts, and the amplifier A1
The voltage v8 at the non-inverting input of the amplifier A3 and the voltage V at the non-inverting input of the amplifier A3 are obtained.
従ってトランジスタＴ ｒ ｇ Ｔｒｙのコレクタ電流
をＩ、、 Ｉ、とすると下記の如くなる。Therefore, if the collector current of the transistor T r g Try is I,, I, it becomes as follows.
加入者電話機を利用している場合、すなわちオフフック
時は、上記電流Ｉ’、、、Ｉ、が図示の向きで流ｎ１且
つ監視電圧Ｖ、に依存して定電流にされる。When the subscriber telephone is in use, i.e. when off-hook, the currents I', .
しかしながら、オンフックとなシ、通話路ＢとＡとは開
放さｎ１上記電流Ｉ、、ＩＡは流れなくなる。However, when on-hook, communication paths B and A are opened, and the currents I, , IA no longer flow.
ところが、増幅器Ａ１の非反転入力端子には上記同様の
電圧ｖ１が印加され、反転入力端子は抵抗”１３ Ｒｔ
１を介して接地されているから、増幅器Ａｌには図示
の如（Ｉ、が流れる。同様に増幅器Ａ、にも図示の如く
Ｉ８′が流れる。これらの電流ｌ８１１、Ｉは増幅器Ａ
、、Ａ、の飽和電流、或いは、前述の！１■、と等しい
値である。However, the same voltage v1 as above is applied to the non-inverting input terminal of the amplifier A1, and the inverting input terminal is connected to the resistor "13 Rt.
1, so that (I) flows through the amplifier Al as shown in the figure.Similarly, I8' flows through the amplifier A as shown in the figure.These currents l811 and I flow through the amplifier A.
, ,A, or the saturation current of ! The value is equal to 1■.
すなわち、第１図に図示の従来の定電流給電回路によれ
ば、オン７．り又はオフフックのいずれの場合もほぼ同
等の電力消費とカシ、オンフック時にも電力が浪費きれ
ているととＫなる。時間的にみれば、一般にオフフック
時に比しオン７．り時が非常に長いから、この電力は本
来必要とされるものに比し相尚浪費されていることにな
る。That is, according to the conventional constant current power supply circuit shown in FIG. The power consumption is almost the same in either case of on-hook or off-hook, and the power is not wasted even when on-hook. In terms of time, in general, the on-hook period is 7. This power is wasted compared to what is actually needed, since the waiting time is very long.
発明の目的
本発明の目的は、加入者電話機がオアフ、り時において
は従来通シ定電流給電を可能とすると共に、オンフック
時は無効な電流が流れないようにし消費電力の節約を図
ることができるディジタル交換機の加入者回路の定電流
給電回路を提供することにある。OBJECTS OF THE INVENTION An object of the present invention is to enable constant current power supply when a subscriber's telephone is off-hook, and to save power consumption by preventing invalid current from flowing when on-hook. An object of the present invention is to provide a constant current power supply circuit for a subscriber circuit of a digital exchange.
発明の構成
本発明においては、通話路線間電圧の中点電圧を監視す
る手段、通話路線のそれぞれ対称的に設けられ上記監視
手段の監視電圧を負帰還電圧として印加され該負帰還電
圧に応答して通話路線に流れる電流を一定に維持するよ
りにした第１及び第２の制御手段を有するディジタル交
換機の加入者回路の定電流給電回路において、前記第１
及び第２の制御手段のそれぞれの前記負帰還電圧印加部
に、前記通話路が開放の場合、前記負帰還電圧を基準電
圧とほぼ等しくする第１及び第２の補償手段を設けたこ
とを特徴とする、定電流給電回路が提供される。Structure of the Invention In the present invention, a means for monitoring the midpoint voltage of the voltage between communication lines is provided symmetrically with each of the communication lines, and the monitoring voltage of the monitoring means is applied as a negative feedback voltage, and the monitoring means responds to the negative feedback voltage. In a constant current power supply circuit for a subscriber circuit of a digital exchange, the first and second control means are configured to maintain a constant current flowing through a communication line.
and a first and second compensating means for making the negative feedback voltage substantially equal to a reference voltage when the communication path is open are provided in each of the negative feedback voltage application sections of the second control means. A constant current power supply circuit is provided.
発明の実施例
、 以下本発明の一実施例について、第２図を参照し
て述べる。Embodiment of the Invention An embodiment of the invention will be described below with reference to FIG.
本発明の定電流給電回路には、加入者電話機（図示せず
）に接続される通話路Ａ、Ｂの線、間に線間電圧の中点
電圧を監視する手段として抵抗器Ｒ□５．Ｒ□、演算増
幅器Ａ３から成る回路が設けられている。通話路Ｂと地
気（接地）０間には、通話路に一定電流を流す第１の制
御手段として抵抗器Ｒ３□、トランジスタＴｒ、 、演
算増幅器Ａ１′からなる回路が設けられている。また通
話路Ａと電源ｖ！１ｍ１１例えば−４８Ｖとの間に上記
第１の制御手段と対称的に、通話路に一定電流を流す第
２の制御手段として抵抗器Ｒ２□、トランジスタＴｒ、
、演算増幅器Ａ、から成る回路が設けられている。The constant current power supply circuit of the present invention includes a resistor R□5. as means for monitoring the midpoint voltage of the line voltage between the lines of communication paths A and B connected to a subscriber telephone (not shown). A circuit consisting of R□ and operational amplifier A3 is provided. A circuit consisting of a resistor R3□, a transistor Tr, and an operational amplifier A1' is provided between the communication path B and the earth (ground) 0 as a first control means for causing a constant current to flow through the communication path. Also, communication path A and power supply V! 1m11 For example, in contrast to the first control means, a resistor R2□, a transistor Tr,
, operational amplifier A, is provided.
また演算増幅話人、の出力電圧、すなわち通話路線の中
点電圧Ｖ、は抵抗器Ｒ１４１Ｒ１４を介して、負帰還信
号として、それぞれ演算増幅器Ａ１及びＡ、の非反転入
力端子に接続されている。Further, the output voltage of the operational amplifier talker, ie, the midpoint voltage V of the communication line, is connected to the non-inverting input terminals of operational amplifiers A1 and A, respectively, as a negative feedback signal via resistors R141R14.
増幅器Ａ８の非反転入力端子はさらに抵抗器Ｒ１，を介
して地気Ｇに接続されておシ、基準入力印加端子として
の反転入力・端子は抵抗器Ｒ１□を介して地気Ｇに接地
されると共にトランジスタＴｒ□のエミッタに接続され
ている。増幅器Ａ１の出力はトランジスタＴｒｌのペー
スに接続されている。The non-inverting input terminal of the amplifier A8 is further connected to the earth G through a resistor R1, and the inverting input terminal serving as a reference input application terminal is grounded to the earth G through a resistor R1□. and is connected to the emitter of the transistor Tr□. The output of amplifier A1 is connected to the pace of transistor Trl.
増幅器Ａ、の非反転入力端子にもさらに抵抗器Ｒ１ｔを
介して電源ｖｍｍｌに接続されておシ、基準入力印加端
子としての反転入力端子は抵抗器Ｒｘｔを介して電源■
、に接続されている。増幅器Ａ、の出力はトランジスタ
Ｔｒ２のベースに接続されている。The non-inverting input terminal of the amplifier A is also connected to the power supply vmml via a resistor R1t, and the inverting input terminal as a reference input application terminal is connected to the power supply Vmml via a resistor Rxt.
,It is connected to the. The output of amplifier A is connected to the base of transistor Tr2.
通話路Ｂ、Ａ間のオフフックを検出するため一次側に直
流分カット用キャノ９シタＣが設けられている変圧器Ｔ
が接続されている。A transformer T is equipped with a DC cutoff canopy C on the primary side to detect off-hook between communication paths B and A.
is connected.
当該定電流給電回路が設けられている局と加入者電話機
との距離が近い場合には、図中破線で示した抵抗器Ｒｔ
ｓ ＊ Ｒ！ ｓが設けられる場合がある。If the distance between the station where the constant current feeding circuit is installed and the subscriber telephone is close, the resistor Rt shown by the broken line in the figure
s*R! s may be provided.
上述の回路構成は、従来の定電流給電回路として図示し
たものと同様である。しかしながら第２図の回路におい
ては更に下記のものが設けられている。The circuit configuration described above is similar to that illustrated as a conventional constant current power supply circuit. However, the circuit of FIG. 2 further includes the following:
抵抗器Ｒ１ｍ ｌ Ｒ１４と演算増幅器Ａ１の非反転入
力端子の結合点にカソードが接続されたダイオードＤ１
、該ダイオードのアノードに出力端子が接続された演算
増幅器Ａ、が設けられている。Diode D1 whose cathode is connected to the connection point between resistor R1m l R14 and the non-inverting input terminal of operational amplifier A1.
, an operational amplifier A whose output terminal is connected to the anode of the diode is provided.
また抵抗器Ｒ２，、Ｒ２２と演算増幅器Ａ２の非反転入
力端子の結合点にアノードが接続さ扛たダイオードＤ２
、該ダイオードのカソードに出力端子が接続された演算
増幅器Ａ、が設けられている。In addition, a diode D2 whose anode is connected to the connection point between the resistors R2, R22 and the non-inverting input terminal of the operational amplifier A2
, an operational amplifier A whose output terminal is connected to the cathode of the diode.
さらに電源ｖＢＢと地気Ｇとの間に抵抗器Ｒ１，。Furthermore, a resistor R1 is connected between the power supply vBB and the earth G.
Ｒ１＃Ｒ２６の直列回路が並列に設けられ、抵抗器Ｒ１
６とＲ□の接合点は演算増幅器Ａ４の反転入力端子に接
続され、抵抗器Ｒ１とｌＲｇａの結合点は演算増幅器Ａ
、の反転入力端子に接続されている。A series circuit of R1#R26 is provided in parallel, and the resistor R1
The junction between 6 and R□ is connected to the inverting input terminal of operational amplifier A4, and the junction between resistors R1 and lRga is connected to operational amplifier A.
, is connected to the inverting input terminal of .
演算増幅器、Ａ４の非反転入力端子は通話路Ｂに接続さ
れ、また演算増幅器Ａ、の非反転入力端子は通話路Ａに
接続されている。The non-inverting input terminal of operational amplifier A4 is connected to communication path B, and the non-inverting input terminal of operational amplifier A is connected to communication path A.
ここで、演算増幅器Ａ４は線路Ｂ上の電圧ｖｘを監視す
る作用を持ち、反転入力端子に印加される電圧ＶＴＨＢ
は、オンフック時ｖｘ＞ｖ、ＨＢ、オフフック時ｖｘ＜
ｖＴＨｌｌ となるように回路を設計しておく。また演
算増幅器Ａ、は線路Ａ上の電圧ｖ１を監視する働きを持
ち、反転入力端子に印加される電圧は、オンフック時η
＜■ＴＨＡＴオンフック時η〉■□、となるように回路
を設計しておく。Here, the operational amplifier A4 has the function of monitoring the voltage vx on the line B, and the voltage VTHB applied to the inverting input terminal.
is vx>v when on-hook, HB, vx< when off-hook
The circuit is designed so that vTHll. In addition, operational amplifier A has the function of monitoring voltage v1 on line A, and the voltage applied to the inverting input terminal is η when on-hook.
The circuit is designed so that <■THAT on-hook η>■□.
以下第２図回路の動作について説明する。The operation of the circuit shown in FIG. 2 will be explained below.
まずオフフックの場合について述べる。この場合通話路
Ｂ、Ａが閉路される。従って従来の定電流給電回路の場
合と同様に電流ＩＢ、 Ｉ、が図示の向きで流れる。First, let us discuss the off-hook case. In this case, communication paths B and A are closed. Therefore, the currents IB and I flow in the directions shown in the figure, as in the case of the conventional constant current power supply circuit.
ここで、増幅器Ａ４の非反転入力端子には通話路Ｂ上の
電圧ｖｘが印加され、反転入力端子にはｖＴ□〉ｖｘな
るしきい値電圧ｖＴＨＩＩが印加される。Here, the voltage vx on the communication path B is applied to the non-inverting input terminal of the amplifier A4, and the threshold voltage vTHII of vT□>vx is applied to the inverting input terminal.
従って増幅器Ａ４の出力は＝（ｖＴＩＩＢ−ｖｘ）の負
電位となるが、図示の向きで逆阻止用ダイオードＤ１が
設けられているので、増幅器Ａ、の出力は増幅器Ａ、の
非反転入力端子には印加さｆず、上記（３）式の如き電
流■３が制御される。Therefore, the output of amplifier A4 becomes a negative potential of = (vTIIB-vx), but since the reverse blocking diode D1 is provided in the direction shown, the output of amplifier A is connected to the non-inverting input terminal of amplifier A. is not applied, and the current (3) as shown in equation (3) above is controlled.
同様に、増幅器Ａ、の非反転入力端子には通路Ａ上の電
圧ｖＹが印加され、反転入力端子にはｖＴＨＡ＜ｖＹ表
るしきい値電圧■ＴＨＡが印加される。Similarly, the voltage vY on the path A is applied to the non-inverting input terminal of the amplifier A, and the threshold voltage .OMEGA.THA, where vTHA<vY, is applied to the inverting input terminal.
従って増幅器Ａ、の出力は（ｖＹ−ｖＴＩ（Ａ）の正電
位と々るが、図示の向きで逆阻止用ダイオードＤ。Therefore, the output of the amplifier A reaches a positive potential of (vY-vTI(A)), but the reverse blocking diode D is connected in the direction shown.
が設けられているので増幅器Ａ、の非反転入力端子は増
幅器Ａ２の出力電圧の影＊Ｖ受けず、上記（４）式の如
き電流ＩＡが制御される。is provided, the non-inverting input terminal of amplifier A is not affected by the output voltage *V of amplifier A2, and the current IA is controlled as shown in equation (4) above.
以上述べたように、オフフック時は、増幅器Ａ４．Ａ、
の出力電圧は定電流制御回路に何ら影響を及ぼさないか
ら、従来同様定電流を供給することができる。As mentioned above, when off-hook, amplifier A4. A,
Since the output voltage has no effect on the constant current control circuit, a constant current can be supplied as in the conventional case.
次にオンフ、り時について述べる。この場合、通話路Ｂ
、Ａは開放状態となっている。従ってｉ、＝Ｑ、ｉ、＝
Ｑである。増幅器Ａ４＃Ａ５がない場合の増幅器ＡＩ
ｌＡｌの非反転入力端子にはそれぞれ、上記（１）
Ｌ （２）式で示された電圧が印加されるが、増幅器Ａ
４．Ａ１によシ、増幅器Ａｌ＋ＡＩの非反転入力端子の
電圧ｖ、’、ｖ、’はそれぞれ次のようになる。Next, let's talk about on-off and on-off times. In this case, call path B
, A are in an open state. Therefore, i,=Q,i,=
It is Q. Amplifier AI when there is no amplifier A4#A5
The above (1) is applied to the non-inverting input terminal of lAl.
L The voltage shown in equation (2) is applied, but the amplifier A
4. For A1, the voltages v,', v,' at the non-inverting input terminal of the amplifier Al+AI are as follows.
増幅器Ａ４の反転入力端子の電圧ｖＴ□はｖＴ□＜ｖｘ
であるから、増幅４人４の出力レベルが地気に対して高
となシ、ダイオードＤ１の順方向に、電流が流れ、電圧
ｖ１′をほぼ地気レベルにする。これによシ増幅器Ａ、
の両入力端子は同レベルとなシ、従来のような電流Ｉ、
（第（３）式参照）は流れない。The voltage vT□ at the inverting input terminal of amplifier A4 is vT□<vx
Therefore, when the output level of the four amplifiers 4 is high relative to the earth's level, a current flows in the forward direction of the diode D1, making the voltage v1' almost at the earth's level. With this, amplifier A,
Both input terminals are at the same level, so the current I,
(see equation (3)) does not flow.
また増幅器Ａ、の反転入力端子の電圧ｖＴＨＡは■Ｙ＞
ｖＴＨＡであるから、ダイオードＤｓＯ順方向に電流が
流れ、電圧ｙ、 ／を電源Ｖ□とはｔ！同じレベルにす
る・これによ〕増幅器Ａ！の両入力端子は同レベルとな
シ従来のような電流Ｉｓ′（第（４）式参照）は流れな
い。Also, the voltage vTHA at the inverting input terminal of amplifier A is ■Y>
Since vTHA, current flows in the forward direction of the diode DsO, and the voltage y, / is t! Make it the same level with this] Amplifier A! Since both input terminals are at the same level, the current Is' (see equation (4)) as in the conventional case does not flow.
以上述べたように、オン７．り時において、ダイオード
ＤＩ 、増幅４人４によシ増幅器ＡＨの非反転入力端子
の印加電圧ｖ１′を地気レベル、ダイオードＤｌｘ増幅
器Ａ、によ）増幅器Ａ、の非反転入力端子の印加電圧ｙ
、 ／を電源レベルとすることによシ、定電流制御回路
を実質的に不動作状態にする。As mentioned above, on 7. At this time, diode DI and amplifier AH set the applied voltage v1' at the non-inverting input terminal to the ground level, and diode Dlx amplifier A set the applied voltage at the non-inverting input terminal of amplifier A to the ground level. y
, / are set to the power supply level, thereby rendering the constant current control circuit substantially inactive.
発明の効果
以上に述べたように本発明によれば比較的簡単な回路構
成によシ、オフトラック時のみ定電流を供給することが
でき、時間的には大部分がオントラック状態である時に
費やされていた電力を大幅に節約することができる。Effects of the Invention As described above, according to the present invention, a constant current can be supplied only when off-track, using a relatively simple circuit configuration, and when most of the time is on-track. The amount of electricity that would otherwise have been consumed can be significantly saved.
第１図は従来の定電流給電回路図、第２図は本発明の一
実施例としての定電流給電回路図、である。
（符号の説明）
Ｒ１＃Ｒ１１〜ａＳＳ・・・抵抗器、Ａ１％ＡＩ・・・
演算増幅器、Ｔｒｉ＋Ｔｒ鵞・・・トランジスタ、Ｄｌ
、Ｄ。
・・・ダイオード、Ｔ・・・変圧器、Ｃ・・・キャノ４
シタ。FIG. 1 is a conventional constant current feeding circuit diagram, and FIG. 2 is a constant current feeding circuit diagram as an embodiment of the present invention. (Explanation of symbols) R1#R11~aSS...Resistor, A1%AI...
Operational amplifier, Tri+Tr...transistor, Dl
,D. ...Diode, T...Transformer, C...Cano 4
Sita.
Claims (1)
線のそれぞれに対称的に設けられ上記監視手段の監視電
圧を負帰還電圧として印加され該負帰還電圧に応答して
通話路線に流れる電流を一定に維持するようにした第１
及び第２の制御手段を有するディジタル交換機の加入者
回路の定電流給電回路において、前記第１及び第２の制
御手段のそれぞれの前記負帰還電圧印加部に、前記通話
路が開放の場合、前記負帰還電圧を基準電圧とほぼ等し
くする第１及び第２の補償手段を設けたことを特徴とす
る、定電流給電回路。1. Means for monitoring the midpoint voltage of the voltage between communication lines, which is provided symmetrically on each of the communication lines, and the monitoring voltage of the monitoring means is applied as a negative feedback voltage, and the voltage flows to the communication line in response to the negative feedback voltage. The first method is to maintain a constant current.
and a constant current feeding circuit of a subscriber circuit of a digital exchange having a second control means, when the communication path is open to the negative feedback voltage application section of each of the first and second control means, the A constant current power supply circuit comprising first and second compensation means for making a negative feedback voltage substantially equal to a reference voltage.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59120666A JPS615669A (en) | 1984-06-14 | 1984-06-14 | Constant current feeding circuit of subscriber circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59120666A JPS615669A (en) | 1984-06-14 | 1984-06-14 | Constant current feeding circuit of subscriber circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS615669A true JPS615669A (en) | 1986-01-11 |
Family
ID=14791901
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP59120666A Pending JPS615669A (en) | 1984-06-14 | 1984-06-14 | Constant current feeding circuit of subscriber circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS615669A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63503269A (en) * | 1986-05-06 | 1988-11-24 | テレフオンアクチーボラゲツト エル エム エリクソン | Telephone power supply equipment used within telecommunications systems |
| JPH08242A (en) * | 1994-06-21 | 1996-01-09 | Sato Noki Kk | Vegetable washing machine |
| CN1058119C (en) * | 1996-11-15 | 2000-11-01 | 刘海先 | Constant-current and constant-voltage feeder apparatus |
-
1984
- 1984-06-14 JP JP59120666A patent/JPS615669A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63503269A (en) * | 1986-05-06 | 1988-11-24 | テレフオンアクチーボラゲツト エル エム エリクソン | Telephone power supply equipment used within telecommunications systems |
| JPH08242A (en) * | 1994-06-21 | 1996-01-09 | Sato Noki Kk | Vegetable washing machine |
| CN1058119C (en) * | 1996-11-15 | 2000-11-01 | 刘海先 | Constant-current and constant-voltage feeder apparatus |
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