JP2576463B2 - Driving circuit - Google Patents
Driving circuitInfo
- Publication number
- JP2576463B2 JP2576463B2 JP20564085A JP20564085A JP2576463B2 JP 2576463 B2 JP2576463 B2 JP 2576463B2 JP 20564085 A JP20564085 A JP 20564085A JP 20564085 A JP20564085 A JP 20564085A JP 2576463 B2 JP2576463 B2 JP 2576463B2
- Authority
- JP
- Japan
- Prior art keywords
- voltage
- resistor
- terminal
- power supply
- output
- 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
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
- H05B45/30—Driver circuits
- H05B45/395—Linear regulators
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
- H05B45/50—Circuit arrangements for operating light-emitting diodes [LED] responsive to malfunctions or undesirable behaviour of LEDs; responsive to LED life; Protective circuits
- H05B45/56—Circuit arrangements for operating light-emitting diodes [LED] responsive to malfunctions or undesirable behaviour of LEDs; responsive to LED life; Protective circuits involving measures to prevent abnormal temperature of the LEDs
-
- 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
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
- Y02B20/30—Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]
Landscapes
- Dot-Matrix Printers And Others (AREA)
- Led Devices (AREA)
- Electronic Switches (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、LEDプリンタの発光ダイオードアレイ(以
下、LEDアレイという)駆動用ICの出力電流制御に関す
る。Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to output current control of an IC for driving a light emitting diode array (hereinafter, referred to as an LED array) of an LED printer.
本発明は、LEDプリンタのLEDアレイ駆動用ICにおい
て、電源間に抵抗を接続してその任意の中間点を外部に
取り出せる構成にし、その中間点の電圧をオン状態での
出力のPチヤネル型オープンドレイン出力MOSトランジ
スタのゲート入力電圧にするとともに、上記の中間点と
電源間に外付け抵抗を設けることにより、LEDアレイを
駆動する出力電流の制御を、容易にかつ低コストで実現
したものである。The present invention relates to an LED array driving IC of an LED printer, in which a resistor is connected between power supplies so that an arbitrary intermediate point can be taken out to the outside, and a voltage at the intermediate point is output in a P-channel open state in an ON state. By controlling the output current to drive the LED array easily and at low cost, by providing the gate input voltage of the drain output MOS transistor and providing an external resistor between the intermediate point and the power supply. .
LEDプリンタは、LEDをアレイ状または千鳥状に並べ発
光させて、その光をセルフオツクレンズアレイを介して
ドラム上に集光して露光する方式である。LEDアレイ駆
動用ICは、このプリンタ用光源であるLEDアレイの両側
に同時に実装してあり通算64個で1チツプを形成してい
る。The LED printer is a system in which LEDs are arranged in an array or in a staggered manner to emit light, and the light is condensed on a drum via a self-occurring lens array and exposed. The LED array driving ICs are simultaneously mounted on both sides of the LED array, which is a light source for the printer, and a total of 64 ICs form one chip.
従つて、一般に8ドツト/mmならA4判では27個のLEDアレ
イとそれに対応した駆動用ICが必要となる。実際の量産
時における製造上のバラツキに関しては、LEDの輝度の
バラツキは±15%以内であり、同一チツプ内では比較的
バラツキは小さいが、チツプ間のバラツキは大きく、プ
リンタ用光源として均一化をはかるためには、LEDアレ
イと1対1に対応した駆動用IC単位で、LEDアレイを駆
動する電流を制御する必要があつた。Therefore, in general, if the size is 8 dots / mm, an A4 size requires 27 LED arrays and a corresponding driving IC. Regarding the manufacturing variation during actual mass production, the variation in LED brightness is within ± 15%. In order to measure the current, it was necessary to control the current for driving the LED array on a drive IC unit corresponding to the LED array on a one-to-one basis.
前述のLEDアレイを駆動する電流の駆動用IC単位で補
正する方法としては、LEDアレイにあう駆動用ICを選別
する方法が考えられるが、コストアツプにつながり量産
時には実現困難であるという欠点を有していた。As a method of correcting the current for driving the LED array in units of driving ICs, a method of selecting a driving IC that matches the LED array can be considered, but it has a disadvantage that it increases cost and is difficult to realize in mass production. I was
本発明はこのような問題点を解決するもので、その目
的とするところは、LEDアレイを駆動する電流の駆動用I
C単位での電流制御がし易く、かつ、回路を構成する素
子数を少なくして、低コストでバラツキを少なくし、更
に、LEDアレイの温度特性の補正をIC内部で容易に実現
できる回路を提供することにある。The present invention solves such a problem, and an object of the present invention is to provide a current driving IC for driving an LED array.
A circuit that facilitates current control in C units, reduces the number of elements that make up the circuit, reduces variations at low cost, and easily realizes temperature compensation of the LED array inside the IC To provide.
本発明の駆動用回路は、 第1の電源端子と負荷である発光ダイオードとの間に
接続した出力MOSトランジスタと、前記第1の電源端子
と第2の電源端子との電圧を分圧する分圧抵抗と、前記
分圧抵抗の分圧点に接続された電圧制御端子と、出力制
御信号を入力とし前記出力MOSトランジスタのゲートへ
出力が接続されたCMOSインバータとを具備し、前記CMOS
インバータの電源端子が前記第1の電源端子と前記電圧
制御端子に接続され、前記出力MOSトランジスタの出力
電流に基づいて前記発光ダイオードを駆動してなる駆動
用ICと、 前記電圧制御端子と前記第2の電源端子との間であっ
て前記電圧制御端子の制御電圧の調整を可能とする前記
駆動用ICの外部に接続される外付け抵抗、とを有する駆
動回路において、 前記電圧制御端子は、前記分圧抵抗と該分圧抵抗の温
度特性に比べて小さな温度特性を有する前記外付け抵抗
とにより分圧された電圧を出力し、 前記分圧抵抗は、前記駆動用IC内に形成された低濃度
P型不純物層からなる内蔵抵抗であって、 当該内蔵抵抗の温度特性に基づく前記電圧制御端子の
電圧の変化により前記発光ダイオードの温度特性を補償
してなることを特徴とする。A driving circuit according to the present invention includes an output MOS transistor connected between a first power supply terminal and a light emitting diode as a load, and a voltage divider for dividing a voltage between the first power supply terminal and the second power supply terminal. A resistor, a voltage control terminal connected to a voltage dividing point of the voltage dividing resistor, and a CMOS inverter having an output control signal as input and an output connected to the gate of the output MOS transistor, wherein the CMOS
A power supply terminal of an inverter connected to the first power supply terminal and the voltage control terminal; a driving IC configured to drive the light emitting diode based on an output current of the output MOS transistor; An external resistor connected to the outside of the drive IC between the power supply terminal and the power supply terminal, the voltage control terminal comprising: A voltage divided by the voltage dividing resistor and the external resistor having a temperature characteristic smaller than the temperature characteristic of the voltage dividing resistor is output, and the voltage dividing resistor is formed in the driving IC. A built-in resistor comprising a low-concentration P-type impurity layer, wherein a temperature characteristic of the light emitting diode is compensated by a change in a voltage of the voltage control terminal based on a temperature characteristic of the built-in resistor.
本発明の上記の構成によれば、電源間に接続された抵
抗の任意の中間電位をIC外部に取り出す電圧制御端子
(以下、CTL端子という)と電源間に外付け抵抗を設け
ることにより、CTL端子の電圧、即ち、LEDアレイを駆動
するPチヤネル型MOSトランジスタのオン状態でのゲー
ト電圧をチツプ毎に制御できるので、外付け抵抗値を変
更することにより、LEDアレイの輝度特性に応じて、駆
動電流を制御することができる。また、温度上昇ととも
に0.5%/℃で電流が減少するLEDの温度特性に対して、
電源間に接続された抵抗としてP-抵抗を利用すれば、
0.5%/℃で温度上昇とともに抵抗値が上がるので、外
付け抵抗がP-抵抗に比べ温度特性が小さければLEDアレ
イを駆動するPチヤネル型NOSトランジスタのオン状態
でのノースに対するゲート電圧を上昇させることができ
るので、LEDアレイの温度特性をIC内部で補正すること
ができ、LEDアレイの輝度を補償することができる。According to the above configuration of the present invention, by providing an external resistor between a voltage control terminal (hereinafter, referred to as a CTL terminal) for extracting an arbitrary intermediate potential of a resistor connected between power supplies to the outside of the IC and a power supply, The terminal voltage, that is, the gate voltage in the ON state of the P-channel type MOS transistor driving the LED array can be controlled for each chip, so by changing the external resistance value, it is possible to control the LED array according to the luminance characteristics of the LED array. The drive current can be controlled. In addition, for the temperature characteristics of LED where current decreases by 0.5% / ℃ with temperature rise,
If a P - resistor is used as the resistor connected between the power supplies,
Since the resistance value increases as the temperature rises at 0.5% / ° C., if the external resistor has a lower temperature characteristic than the P − resistor, the gate voltage of the P-channel NOS transistor driving the LED array with respect to the north in the ON state is increased. Therefore, the temperature characteristics of the LED array can be corrected inside the IC, and the luminance of the LED array can be compensated.
第1図に本発明による具体的な一実施例を示す。1,2
は、電源間に接続された抵抗(以下、R1,R2という)
3は、Pチヤネル型MOSトランジスタ4は、R1,R2によ
り分割された中間電位をソース電源とするNチヤネル型
MOSトランジスタ、5はPチヤネル型MOSトランジスタ3
とNチヤネル型MOSトランジスタ4より構成されるCMOS
インバータの出力をゲート入力とするPチヤネル型オー
プンドレイン出力MOSトランジスタ(以下、出力トラン
ジスタという) 6は、プラス電源端子(以下、VDD端
子という) 7は、出力トランジスタのオンオフ状態を
制御する出力制御信号 8は、CTL端子 9は、マイナ
ス電源端子(以下VSS端子という) 10は、出力トラン
ジスタのオープンドレイン出力端子 (以下、DO端子と
いう) 11は、電流制御機能付発光ダイオードアレイ駆
動用IC 12は、CTL端子8とVSS端子9の間に接続された
外付け抵抗(以下、Rという) 13は、DO端子10とVSS
端子9の間に接続された発光ダイオードである。FIG. 1 shows a specific embodiment according to the present invention. 1,2
Is the resistance connected between the power supplies (hereinafter referred to as R 1 and R 2 )
Reference numeral 3 denotes a P-channel type MOS transistor 4 and an N-channel type MOS transistor 4 which uses an intermediate potential divided by R 1 and R 2 as a source power source.
MOS transistor 5 is a P-channel type MOS transistor 3
And CMOS comprising N-channel MOS transistor 4
A P-channel open-drain output MOS transistor (hereinafter referred to as an output transistor) having an output of the inverter as a gate input. 6 is a positive power supply terminal (hereinafter referred to as a VDD terminal). 8 is a CTL terminal 9 is a negative power supply terminal (hereinafter referred to as VSS terminal) 10 is an open drain output terminal of an output transistor (hereinafter referred to as DO terminal) 11 is a light emitting diode array driving IC 12 with a current control function 12 is An external resistor (hereinafter referred to as R) 13 connected between the CTL terminal 8 and the VSS terminal 9 is connected to the DO terminal 10 and the VSS
A light emitting diode connected between the terminals 9.
次に第1図の実施例における動作を説明する。VDD端
子6とVSS端子9の間に、電圧VOが印加されると、CTL端
子8には、R1,R2及びRにより分割された以下の式に示
される電圧(以下、VCTLという)が発生する。Next, the operation in the embodiment of FIG. 1 will be described. When a voltage VO is applied between the VDD terminal 6 and the VSS terminal 9, a voltage (hereinafter, referred to as VCTL) divided by R 1 , R 2 and R and expressed by the following equation is applied to the CTL terminal 8. Occur.
このVCTLは、Nチヤネル型MOSトランジスタ4のソー
ス電源であるため、出力トランジスタ5のオンオフ状態
を制御する出力制御信号7をゲート入力とするPチヤネ
ル型MOSトランジスタ3とNチヤネル型MOSトランジスタ
4より構成されるCMOSインバータを通して出力トランジ
スタ5のオン状態でのゲート電圧を与えることになる。 Since this VCTL is a source power supply of the N-channel MOS transistor 4, it is composed of a P-channel MOS transistor 3 and an N-channel MOS transistor 4 whose gate inputs are an output control signal 7 for controlling the on / off state of the output transistor 5. The gate voltage in the ON state of the output transistor 5 is applied through the CMOS inverter to be performed.
一般にMOSトランジスタは、以下の式で表わされる電圧
−電流特性を示す。Generally, a MOS transistor has a voltage-current characteristic expressed by the following equation.
(i) VD<VG-VTM(不飽和領域)では、 (II) VD>VG-VTM(飽和領域)では、 VD ソースドレイン間電圧 VG ソースゲート間電圧 VTM しきい値電圧 β 電圧電流変換係数 従つて、出力トランジスタ5のオン状態では、VG=VC
TLであるため、外付け抵抗Rの値を変更することによ
り、VGの電圧、即ち、出力電流IDを制御することが可能
となる。第2図に、R1=500Ω R2=1000Ω VO=5V
で、β=1×10-3A/V2 VTM=0.7V VD=3.3Vの場合の
外付け抵抗R−駆動電流ID特性を示す。ゆえに、各LED
アレイに対応したLEDアレイ駆動用ICのチツプ毎の外付
け抵抗Rの値を調整すれば、接続されたLEDアレイの輝
度特性に応じて駆動電流を制御することが可能となる。
また、抵抗R1、R2は、P-抵抗により形成された内蔵
抵抗であるため、発光ダイオードの温度特性は、同一の
温度特性を有するP-抵抗により形成された内蔵抵抗に
よって補償され、発光ダイオードの輝度を安定化するこ
とができる。(I) When VD <VG-VTM (unsaturated region), (II) When VD> VG-VTM (saturation region), VD Source-drain voltage VG Source-gate voltage VTM Threshold voltage β Voltage-to-current conversion coefficient Therefore, when output transistor 5 is on, VG = VC
Since it is TL, the voltage of VG, that is, the output current ID can be controlled by changing the value of the external resistor R. In FIG. 2, R 1 = 500Ω R 2 = 1000Ω VO = 5V
Shows an external resistor R-drive current ID characteristic when β = 1 × 10 −3 A / V 2 VTM = 0.7 V VD = 3.3 V. Therefore, each LED
By adjusting the value of the external resistor R for each chip of the LED array driving IC corresponding to the array, it becomes possible to control the driving current according to the luminance characteristics of the connected LED array.
Further, since the resistors R 1 and R 2 are built-in resistors formed by P − resistors, the temperature characteristics of the light emitting diode are compensated by the built-in resistors formed by the P − resistors having the same temperature characteristics, and light emission is performed. The brightness of the diode can be stabilized.
以上述べたように、本発明によれば、電流値の制御を
ICを選別したり、ICの駆動電圧を変更することなく、電
流を外部に供給するトランジスタのゲート電圧を容易に
制御することによって、負荷に適した供給電流を制御す
ることができるというすぐれた効果を有するものであ
る。また、出力トランジスタのゲート電位を設定する抵
抗をP-抵抗を用いて駆動用ICに内蔵するため、負荷で
ある発光ダイオードの温度特性を補償して輝度を安定化
するという格別の効果を有する。As described above, according to the present invention, the control of the current value
The excellent effect that the supply current suitable for the load can be controlled by easily controlling the gate voltage of the transistor that supplies the current without selecting the IC or changing the drive voltage of the IC. It has. In addition, since the resistor for setting the gate potential of the output transistor is built in the driving IC using the P − resistor, the temperature characteristic of the light emitting diode as a load is compensated to stabilize the luminance.
第1図は、本発明による具体的なLEDアレイ駆動用ICの
回路図。 第2図は、第1図の実施例における外付け抵抗R−駆動
電流IDの特性図 1……電源間に接続された抵抗R1 2……電源間に接続された抵抗R2 3……Pチヤネル型MOSトランジスタ 4……Nチヤネル型MOSトランジスタ 5……出力トランジスタ 6……VDD端子 7……出力制御信号 8……CTL端子 9……VSS端子 10……DO端子 11……LEDアレイ駆動用IC 12……外付け抵抗R 13……発光ダイオード。FIG. 1 is a circuit diagram of a specific LED array driving IC according to the present invention. Figure 2 is connected resistors R 2 3 ...... the connected resistor R 1 2 ...... power between between characteristic diagram 1 ...... the power of the external resistor R- drive current ID in the embodiment of Figure 1 P-channel MOS transistor 4 N-channel MOS transistor 5 Output transistor 6 VDD terminal 7 Output control signal 8 CTL terminal 9 VSS terminal 10 DO terminal 11 LED array drive IC 12: External resistor R13: Light-emitting diode.
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 昭60−107372(JP,A) 特開 昭53−26501(JP,A) 特開 昭52−36069(JP,A) 特開 昭55−162120(JP,A) 実開 昭47−31664(JP,U) 実開 昭56−138305(JP,U) 特公 昭60−36134(JP,B2) 特公 昭58−49885(JP,B2) 特公 昭61−5164(JP,B2) ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-60-107372 (JP, A) JP-A-53-26501 (JP, A) JP-A-52-36069 (JP, A) JP-A 55-260 162120 (JP, A) Japanese Utility Model Showa 47-31664 (JP, U) Japanese Utility Model Showa 56-138305 (JP, U) JP-B 60-36134 (JP, B2) JP-B 58-49885 (JP, B2) Tokiko Sho 61-5164 (JP, B2)
Claims (1)
ドとの間に接続した出力MOSトランジスタと、前記第1
の電源端子と第2の電源端子との電圧を分圧する分圧抵
抗と、前記分圧抵抗の分圧点に接続された電圧制御端子
と、出力制御信号を入力とし前記出力MOSトランジスタ
のゲートへ出力が接続されたCOMSインバータとを具備
し、前記CMOSインバータの電源端子が前記第1の電源端
子と前記電圧制御端子に接続され、前記出力MOSトラン
ジスタの出力電流に基づいて前記発光ダイオードを駆動
してなる駆動用ICと、 前記電圧制御端子と前記第2の電源端子との間であって
前記電圧制御端子の制御電圧の調整を可能とする前記駆
動用ICの外部に接続される外付け抵抗、とを有する駆動
回路において、 前記電圧制御端子は、前記分圧抵抗と該分圧抵抗の温度
特性に比べて小さな温度特性を有する前記外付け抵抗と
により分圧された電圧を出力し、 前記分圧抵抗は、前記駆動用IC内に形成された低濃度P
型不純物層からなる内蔵抵抗であって、 当該内蔵抵抗の温度特性に基づく前記電圧制御端子の電
圧の変化により前記発光ダイオードの温度特性を補償し
てなることを特徴とする駆動用回路。An output MOS transistor connected between a first power supply terminal and a light emitting diode as a load;
A voltage dividing terminal for dividing the voltage between the power supply terminal and the second power supply terminal, a voltage control terminal connected to a voltage dividing point of the voltage dividing resistor, and an output control signal as an input to the gate of the output MOS transistor. A COMS inverter having an output connected thereto, wherein a power supply terminal of the CMOS inverter is connected to the first power supply terminal and the voltage control terminal, and drives the light emitting diode based on an output current of the output MOS transistor. An external resistor connected between the voltage control terminal and the second power supply terminal and connected to the outside of the drive IC for enabling adjustment of a control voltage of the voltage control terminal. Wherein the voltage control terminal outputs a voltage divided by the voltage dividing resistor and the external resistor having a smaller temperature characteristic than a temperature characteristic of the voltage dividing resistor; Partial pressure resistor A low-concentration P formed in the drive in the IC
A driving circuit, comprising: a built-in resistor formed of a type impurity layer, wherein a temperature characteristic of the light emitting diode is compensated by a change in a voltage of the voltage control terminal based on a temperature characteristic of the built-in resistor.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP20564085A JP2576463B2 (en) | 1985-09-18 | 1985-09-18 | Driving circuit |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP20564085A JP2576463B2 (en) | 1985-09-18 | 1985-09-18 | Driving circuit |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS6265486A JPS6265486A (en) | 1987-03-24 |
JP2576463B2 true JP2576463B2 (en) | 1997-01-29 |
Family
ID=16510238
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP20564085A Expired - Lifetime JP2576463B2 (en) | 1985-09-18 | 1985-09-18 | Driving circuit |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP2576463B2 (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3134933B2 (en) * | 1987-04-01 | 2001-02-13 | ネックスプレス・ソリューションズ・エルエルシー | Printer device |
JPH079394Y2 (en) * | 1988-07-21 | 1995-03-06 | ローム株式会社 | Integrated circuit device for driving light emitting element |
IT1292717B1 (en) * | 1997-04-24 | 1999-02-11 | Incerti & Simonini Di Incerti | LOW VOLTAGE LIGHTING DEVICE. |
JP6888954B2 (en) * | 2016-12-28 | 2021-06-18 | 京セラ株式会社 | Light emitting device |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS4731664U (en) * | 1971-04-26 | 1972-12-09 | ||
JPS5236069A (en) * | 1975-09-16 | 1977-03-19 | Nippon Denso Co Ltd | Apparatus for detecting physical quantities |
JPS5326501A (en) * | 1976-08-25 | 1978-03-11 | Hitachi Ltd | Signal level conversion circuit |
JPS56138305U (en) * | 1980-03-19 | 1981-10-20 | ||
JPS5849885A (en) * | 1981-09-19 | 1983-03-24 | 朝田 義雄 | Continuous heating and dehydrating device for cloth, etc. through microwave heating |
JPS6036134A (en) * | 1983-08-08 | 1985-02-25 | Toyoda Danball Kogyo Kk | Manufacture of corrugated cardboard fold-molding material made of thermoplastic resin |
JPS60107372A (en) * | 1983-11-17 | 1985-06-12 | Ricoh Co Ltd | Driving method of led array light source |
-
1985
- 1985-09-18 JP JP20564085A patent/JP2576463B2/en not_active Expired - Lifetime
Also Published As
Publication number | Publication date |
---|---|
JPS6265486A (en) | 1987-03-24 |
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Legal Events
Date | Code | Title | Description |
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EXPY | Cancellation because of completion of term |