JPH08766Y2 - LED temperature correction circuit - Google Patents
LED temperature correction circuitInfo
- Publication number
- JPH08766Y2 JPH08766Y2 JP1989138204U JP13820489U JPH08766Y2 JP H08766 Y2 JPH08766 Y2 JP H08766Y2 JP 1989138204 U JP1989138204 U JP 1989138204U JP 13820489 U JP13820489 U JP 13820489U JP H08766 Y2 JPH08766 Y2 JP H08766Y2
- Authority
- JP
- Japan
- Prior art keywords
- led
- resistor
- output
- cds
- signal generator
- 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
Description
【考案の詳細な説明】 ［産業上の利用分野］ この考案は、光通信などに用いるLED光源モジュール
の温度補正回路についてのものである。[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a temperature correction circuit of an LED light source module used for optical communication and the like.
［従来の技術］ 次に、LEDの光出力特性を第３図により説明する。[Prior Art] Next, the light output characteristics of the LED will be described with reference to FIG.
第３図の縦軸は光出力、横軸は設定信号のレベルであ
る。In FIG. 3, the vertical axis represents the optical output and the horizontal axis represents the level of the setting signal.
第３図から明かなように、温度が高く成るにつれて、
光出力は低くなる。As is clear from FIG. 3, as the temperature increases,
Light output is low.
LEDは半導体素子なので、温度により光出力が変化す
る。Since the LED is a semiconductor element, the light output changes with temperature.
そこで、LED駆動回路には、サーミスタなどの感温素
子を用い、温度補正をする。Therefore, a temperature sensitive element such as a thermistor is used in the LED drive circuit to correct the temperature.
次に、従来技術によるLEDの温度補正回路を第４図に
より説明する。Next, a conventional LED temperature correction circuit will be described with reference to FIG.
第４図の１は光出力設定信号を発生する信号発生器、
２はLED、３はサーミスタ、７はLED駆動回路、7Aと7Bは
増幅器である。1 in FIG. 4 is a signal generator for generating an optical output setting signal,
2 is an LED, 3 is a thermistor, 7 is an LED drive circuit, and 7A and 7B are amplifiers.
増幅器7A・7BでLED駆動回路７を構成する。 The LED drive circuit 7 is composed of the amplifiers 7A and 7B.
第４図では、温度の変化に応じて、サーミスタ３の抵
抗値が変わり、LED2の駆動レベルが変わるので、光出力
を補正することができる。In FIG. 4, since the resistance value of the thermistor 3 changes and the drive level of the LED 2 changes according to the change in temperature, the light output can be corrected.
［考案が解決しようとする課題］ 第４図の方法では、第３図の線Ｐ2で補正係数を合わ
せると、線Ｐ3では補正が不足し、線Ｐ1では補正がかか
り過ぎになり、複数の出力点を補正することはできない
という問題がある。[Problems to be Solved by the Invention] In the method of FIG. 4, if the correction coefficients are matched on the line P 2 of FIG. 3 , the line P 3 is insufficiently corrected, and the line P 1 is overcorrected. There is a problem that a plurality of output points cannot be corrected.
この考案は、第４図の回路を発光出力に応じて補正で
きるようにし、光出力のレベルに依存することなく、安
定な出力特性をもつLED駆動回路の提供を目的とする。The purpose of this invention is to provide an LED drive circuit which can correct the circuit of FIG. 4 according to the light emission output and has a stable output characteristic without depending on the level of the light output.
［課題を解決するための手段］ この目的を達成するため、この考案では、光出力設定
信号を発生する信号発生器１と、信号発生器１の出力を
第１の入力端子4Aに接続し、基準電源4Cの電圧を第２の
入力端子4Bに接続する差動増幅回路４と、第１のLED5A
とCdS-Se抵抗器5Bを内蔵し、第１のLED5Aの光出力でCdS
-Se抵抗器5Bの抵抗値が変化するフォトカプラ５と、信
号発生器１の出力を入力に接続し、フォトカプラ５内の
第１のLED5Aを駆動する第１のLED駆動回路６と、差動増
幅回路４の出力に接続され、フォトカプラ５内のCdS-Se
抵抗器5Bと並列に接続されるサーミスタ３と、CdS-Se抵
抗器5Bとサーミスタ３の並列回路を入力に接続し、第２
のLED2を駆動する第２のLED駆動回路７とを備え、第２
のLED2の温度補正をする。[Means for Solving the Problem] In order to achieve this object, in the present invention, a signal generator 1 for generating an optical output setting signal and an output of the signal generator 1 are connected to a first input terminal 4A, The differential amplifier circuit 4 for connecting the voltage of the reference power source 4C to the second input terminal 4B and the first LED 5A
And CdS-Se resistor 5B are built-in, and the optical output of the first LED 5A is CdS.
-The difference between the photocoupler 5 in which the resistance value of the Se resistor 5B changes and the first LED drive circuit 6 which connects the output of the signal generator 1 to the input and drives the first LED 5A in the photocoupler 5, CdS-Se in the photocoupler 5 connected to the output of the dynamic amplifier circuit 4.
The thermistor 3 connected in parallel with the resistor 5B and the parallel circuit of the CdS-Se resistor 5B and the thermistor 3 are connected to the input, and the second
And a second LED drive circuit 7 for driving the LED 2 of
Correct the temperature of LED2.
次に、この考案によるLEDの温度補正回路の構成を第
１図により説明する。Next, the configuration of the LED temperature correction circuit according to the present invention will be described with reference to FIG.
第１図の４は差動増幅器、4C基準電源、5AはLED、5B
はCdS-Se抵抗器、５はフォトカプラ、６はLED駆動回
路、6Aと6Bは増幅器、8A〜8Cは抵抗であり、その他は第
４図と同じである。In Fig. 1, 4 is a differential amplifier, 4C reference power source, 5A is LED, 5B
Is a CdS-Se resistor, 5 is a photocoupler, 6 is an LED drive circuit, 6A and 6B are amplifiers, 8A to 8C are resistors, and others are the same as in FIG.
増幅器6A・6BでLED駆動回路６を構成する。 The LED drive circuit 6 is composed of the amplifiers 6A and 6B.
差動増幅器４の入力端子4Aには信号発生器１からの光
出力設定信号を加え、入力端子4Bには基準電源4Cの電圧
を加える。The optical output setting signal from the signal generator 1 is applied to the input terminal 4A of the differential amplifier 4, and the voltage of the reference power source 4C is applied to the input terminal 4B.
差動増幅器４は基準電源4Cの電圧と信号発生器１の出
力との差の電圧を出す。The differential amplifier 4 outputs a voltage difference between the voltage of the reference power source 4C and the output of the signal generator 1.
LED5AとCdS-Se抵抗器5Bでフォトカプラ５を形成す
る。The LED 5A and the CdS-Se resistor 5B form the photocoupler 5.
LED駆動回路６は、信号発生器１の出力が加えられ、
フォトカプラ５内のLED5Aを駆動する。The output of the signal generator 1 is added to the LED drive circuit 6,
The LED 5A in the photo coupler 5 is driven.
フォトカプラ５内のCdS-Se抵抗器5B、サーミスタ３お
よび抵抗8Bは並列に接続される。The CdS-Se resistor 5B, the thermistor 3 and the resistor 8B in the photocoupler 5 are connected in parallel.
CdS-Se抵抗器5B・サーミスタ３・抵抗器8Bの並列回路
は、差動増幅器４とLED駆動回路７の増幅器7A間に接続
される。The parallel circuit of the CdS-Se resistor 5B, the thermistor 3, and the resistor 8B is connected between the differential amplifier 4 and the amplifier 7A of the LED drive circuit 7.
フォトカプラ５内のCdS-Se抵抗器5Bは、その抵抗値が
LED5Aの発光出力で変化する。The resistance value of the CdS-Se resistor 5B in the photocoupler 5 is
It changes according to the light emission output of LED5A.
次に、LED5AとCdS-Se抵抗器5Bの特性を第２図により
説明する。Next, the characteristics of the LED 5A and the CdS-Se resistor 5B will be described with reference to FIG.
第２図の縦軸はCdS-Se抵抗器5Bの抵抗値、横軸はLED5
Aの順電流である。The vertical axis of Fig. 2 is the resistance value of CdS-Se resistor 5B, and the horizontal axis is LED5.
It is the forward current of A.
第２図から、LED5Aの光出力でCdS-Se抵抗器5Bの抵抗
値が変化するので、LED5Aの光出力に応じて、LED駆動回
路６の駆動レベルを補正することができる。From FIG. 2, since the resistance value of the CdS-Se resistor 5B changes with the light output of the LED 5A, the drive level of the LED drive circuit 6 can be corrected according to the light output of the LED 5A.
［作用］ 次に、第１図の作用を説明する。[Operation] Next, the operation of FIG. 1 will be described.
信号発生器１の出力は−5V〜0Vである。 The output of the signal generator 1 is -5V to 0V.
基準電源4Cの電圧を−5Vとし、信号発生器１の出力を
0Vに設定したとき、差動増幅器４の出力ＶINは−5Vにな
る。Set the voltage of the reference power supply 4C to -5V, and set the output of the signal generator 1 to
When set to 0V, the output V IN of the differential amplifier 4 becomes -5V.
信号発生器１の出力が0Vとすると、抵抗8Aの両端の電
位差は0Vになるので、フォトカプラ５内のLED5Aには電
流が流れない。したがって、CdS-Se抵抗器5Bの抵抗値は
第２図から∞になる。If the output of the signal generator 1 is 0V, the potential difference across the resistor 8A becomes 0V, so that no current flows through the LED 5A in the photocoupler 5. Therefore, the resistance value of the CdS-Se resistor 5B becomes ∞ from FIG.
抵抗8Bの抵抗値Ｒ8Bを3kΩ、抵抗8Dの抵抗値Ｒ8Bを0.
03kΩ、抵抗8Eの抵抗値Ｒ8Eを3.3kΩとすると、LED駆動
回路７の入力電圧ＶCは、 ＶC＝ＶIN×Ｒ8E／（ＲT＋Ｒ8D＋Ｒ8E） ＝−5V×3.3kΩ／（ＲT＋0.03kΩ＋3.3kΩ） ……
（１） ここで、 ＲT＝Ｒ8B×ＲL×ＲTH／（ＲTH×ＲL ＋ＲL×Ｒ8B＋Ｒ8B×ＲTH） ＝3kΩ×ＲL×ＲTH／（ＲTH×ＲL ＋3kΩ×ＲL＋3kΩ×ＲTH） ＝3kΩ×ＲTH／（3kΩ＋ＲTH） であり、ＲTHはサーミスタ３の抵抗値、ＲLはCdS-Se抵
抗器5Bの抵抗値である。The resistance value R 8B resistor 8B 3 k [Omega, the resistance value R 8B resistor 8D 0.
Assuming that the resistance value R 8E of the resistor 8E is 03 kΩ and 3.3 kΩ, the input voltage V C of the LED drive circuit 7 is: V C = V IN × R 8E / (R T + R 8D + R 8E ) =-5 V × 3.3 kΩ / ( RT + 0.03kΩ + 3.3kΩ)
(1) where R T = R 8B × R L × R TH / (R TH × R L + R L × R 8B + R 8B × R TH ) = 3 kΩ × R L × R TH / (R TH × R L +3 kΩ × RL +3 kΩ × R TH ) = 3 kΩ × R TH / (3 kΩ + R TH ), where R TH is the resistance value of the thermistor 3 and RL is the resistance value of the CdS-Se resistor 5B.
サーミスタ３のＢ定数を3950K,25℃のとき、抵抗値Ｒ
Oを50KΩとすると、サーミスタ３の温度に対する抵抗値
ＲTHは次の式（２）になる。When the B constant of the thermistor 3 is 3950K and 25 ° C, the resistance value R
When O is 50 KΩ, the resistance value R TH with respect to the temperature of the thermistor 3 is given by the following equation (2).
ＲTH＝ＲO exp B（1/T−1/T0） ＝50kΩ exp 3950（1/T−1/298） ……（２） 式（１）と式（２）から、25℃、−10℃および50℃の
ときの入力電圧ＶCはそれぞれ次のようになる。 R TH = R O exp B ( 1 / T-1 / T 0) = 50kΩ exp 3950 (1 / T-1/298) ...... (2) equation (1) from equation (2), 25 ℃, - The input voltages V C at 10 ° C. and 50 ° C. are as follows, respectively.
25℃のとき、ＶC1＝−2.679V −10℃のとき、ＶC2＝−2.619V 50℃のとき、ＶC3＝−2.797V したがって、25℃に対する−10℃の補正量は、 （ＶC2−ＶC1）/VC1×100＝−2.24％ になる。At 25 ° C., V C1 = −2.679V −10 ° C., V C2 = −2.619V At 50 ° C., V C3 = −2.797V Therefore, the correction amount of −10 ° C. for 25 ° C. is (V C2 −V C1 ) / V C1 × 100 = −2.24%.
また、25℃に対する50℃のときの補正量は、 （ＶC3−ＶC1）/VC1×100＝−4.40％ になる。Further, the correction amount at 50 ° C. with respect to 25 ° C. is (V C3 −V C1 ) / V C1 × 100 = −4.40%.
このとき、抵抗8Cの抵抗値Ｒ8C＝91kΩとすれば、LED
2には、 ＶC1/R12＝−2.679V/91kΩ＝−28mA の電流が流れ、LED2の光出力は約0.2μＷとなる。At this time, if the resistance value of the resistor 8C is R 8C = 91kΩ, the LED
A current of V C1 / R 12 = −2.679V / 91kΩ = −28mA flows through 2, and the light output of LED2 is about 0.2 μW.
次に、信号発生器１の出力を−2.5Vに設定すると、差
動増幅器３の出力ＶINは−2.5Vとなる。また、抵抗8Aの
抵抗値Ｒ8Aを68kΩとすると、抵抗8Aの両端の電位差が
2.5Vになるので、LED5Aに流れる電流は、 2.5V/R8A＝2.5V/68kΩ＝36.8μＡ となり、CdS-Se抵抗器5Bの抵抗値は、90kΩになる。Next, when the output of the signal generator 1 is set to -2.5V, the output V IN of the differential amplifier 3 becomes -2.5V. If the resistance value R 8A of the resistor 8A is set to 68 kΩ, the potential difference across the resistor 8A becomes
Since it becomes 2.5V, the current flowing to LED5A becomes 2.5V / R 8A = 2.5V / 68kΩ = 36.8μA, and the resistance value of CdS-Se resistor 5B becomes 90kΩ.
LED2の光出力が0.2μＷのときと同じように、25℃、
−10℃および50℃のときの入力電圧ＶCはそれぞれ次の
ようになる。Same as when the light output of LED2 is 0.2μW, 25 ℃,
Input voltages V C at −10 ° C. and 50 ° C. are as follows, respectively.
25℃のとき、ＶC1＝−1.358V −10℃のとき、ＶC2＝−1.330V 50℃のとき、ＶC3＝−1.415V したがって、25℃に対する補正量は、−10℃のときが
−2.06％、50℃のときが−4.20％になる。At 25 ° C., V C1 = −1.358V −10 ° C., V C2 = −1.330V, at 50 ° C. V C3 = −1.415V Therefore, the correction amount for 25 ° C. is −10 ° C. 2.06%, −50% at −4.20%.
このとき、LED2に流れる電流は、 ＶC1/R12＝1.358V/91＝15mA となり、LED2の光出力は約0.1μＷである。At this time, the current flowing through LED2 is V C1 / R 12 = 1.358V / 91 = 15mA, and the light output of LED2 is about 0.1 μW.
25℃に対する補正量は、LED2の出力が0.1μＷのとき
より0.2μＷのときのほうが大きくなる。The correction amount for 25 ° C. is larger when the output of LED2 is 0.2 μW than when it is 0.1 μW.
つまり、第１図ではLED2の光出力によって温度変化に
対する補正量が違う。That is, in FIG. 1, the correction amount for the temperature change differs depending on the light output of LED2.
［考案の効果］ この考案によれば、第１のLEDとCdS-Se抵抗器を内蔵
し、第１のLEDの光出力でCdS-Se抵抗器の抵抗値を変え
るフォトカプラをサーミスタに並列に接続しているの
で、第２のLEDの温度特性が安定したLED光源を提供する
ことができる。[Effect of the Invention] According to the present invention, a photocoupler that incorporates the first LED and the CdS-Se resistor and changes the resistance value of the CdS-Se resistor by the optical output of the first LED is connected in parallel to the thermistor. Since they are connected, it is possible to provide an LED light source with stable temperature characteristics of the second LED.
第１図はこの考案によるLEDの温度補正回路の構成図、
第２図はLED5AとCdS-Se抵抗器4Bの特性曲線図、第３図
はLEDの光出力特性図、第４図は従来技術によるLEDの温
度補正回路である。 １……信号発生器、２……LED、３……サーミスタ、４
……差動増幅器、4C……基準電源、５……フォトカプ
ラ、5A……LED、5B……CdS-Se抵抗器、６……LED駆動増
幅器、6A・6B……増幅器、７……LED駆動増幅器、7A・7
B……増幅器、8A〜8E……抵抗器。FIG. 1 is a block diagram of an LED temperature correction circuit according to the present invention,
FIG. 2 is a characteristic curve diagram of the LED 5A and the CdS-Se resistor 4B, FIG. 3 is a light output characteristic diagram of the LED, and FIG. 4 is a temperature correction circuit of the LED according to the prior art. 1 ... Signal generator, 2 ... LED, 3 ... Thermistor, 4
...... Differential amplifier, 4C …… Reference power supply, 5 …… Photo coupler, 5A …… LED, 5B …… CdS-Se resistor, 6 …… LED drive amplifier, 6A ・ 6B …… Amplifier, 7 …… LED Drive amplifier, 7A ・ 7
B ... Amplifier, 8A-8E ... Resistor.
Claims (1)
（１）と、 信号発生器（１）の出力を第１の入力端子（4A）に接続
し、基準電源（4C）の電圧を第２の入力端子（4B）に接
続する差動増幅回路（４）と、 第１のLED（5A）とCdS-Se抵抗器（5B）を内蔵し、第１
のLED（5A）の光出力でCdS-Se抵抗器（5B）の抵抗値が
変化するフォトカプラ（５）と、 信号発生器（１）の出力を入力に接続し、フォトカプラ
（５）内の第１のLED（5A）を駆動する第１のLED駆動回
路（６）と、 差動増幅回路（４）の出力に接続され、フォトカプラ
（５）内のCdS-Se抵抗器（5B）と並列に接続されるサー
ミスタ（３）と、 CdS-Se抵抗器（5B）とサーミスタ（３）の並列回路を入
力に接続し、第２のLED（２）を駆動する第２のLED駆動
回路（７）とを備え、 第２のLED（２）の温度補正をすることを特徴とするLED
の温度補正回路。1. A signal generator (1) for generating an optical output setting signal, the output of the signal generator (1) is connected to a first input terminal (4A), and the voltage of a reference power source (4C) Built-in differential amplifier circuit (4) connected to the second input terminal (4B), first LED (5A) and CdS-Se resistor (5B),
In the photocoupler (5), connect the photocoupler (5) whose resistance value of the CdS-Se resistor (5B) changes with the optical output of the LED (5A) and the output of the signal generator (1) to the input. CdS-Se resistor (5B) in the photocoupler (5), which is connected to the first LED drive circuit (6) that drives the first LED (5A) and the output of the differential amplifier circuit (4) The second LED drive circuit that drives the second LED (2) by connecting the thermistor (3) connected in parallel with the CdS-Se resistor (5B) and the thermistor (3) in parallel to the input. (7) and LED which is characterized in that the temperature of the second LED (2) is corrected.
Temperature correction circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1989138204U JPH08766Y2 (en) | 1989-11-29 | 1989-11-29 | LED temperature correction circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1989138204U JPH08766Y2 (en) | 1989-11-29 | 1989-11-29 | LED temperature correction circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0377465U JPH0377465U (en) | 1991-08-05 |
| JPH08766Y2 true JPH08766Y2 (en) | 1996-01-10 |
Family
ID=31685319
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1989138204U Expired - Lifetime JPH08766Y2 (en) | 1989-11-29 | 1989-11-29 | LED temperature correction circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH08766Y2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR102692312B1 (en) * | 2021-10-12 | 2024-08-05 | 강성일 | Waterproof device of pump container |
-
1989
- 1989-11-29 JP JP1989138204U patent/JPH08766Y2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0377465U (en) | 1991-08-05 |
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