JPS5979322A - Constant current circuit - Google Patents
Constant current circuitInfo
- Publication number
- JPS5979322A JPS5979322A JP19102982A JP19102982A JPS5979322A JP S5979322 A JPS5979322 A JP S5979322A JP 19102982 A JP19102982 A JP 19102982A JP 19102982 A JP19102982 A JP 19102982A JP S5979322 A JPS5979322 A JP S5979322A
- Authority
- JP
- Japan
- Prior art keywords
- constant current
- transistor
- value
- emitter
- resistance
- 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.)
- Granted
Links
Classifications
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05F—SYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES
- G05F3/00—Non-retroactive systems for regulating electric variables by using an uncontrolled element, or an uncontrolled combination of elements, such element or such combination having self-regulating properties
- G05F3/02—Regulating voltage or current
- G05F3/08—Regulating voltage or current wherein the variable is dc
- G05F3/10—Regulating voltage or current wherein the variable is dc using uncontrolled devices with non-linear characteristics
- G05F3/16—Regulating voltage or current wherein the variable is dc using uncontrolled devices with non-linear characteristics being semiconductor devices
- G05F3/20—Regulating voltage or current wherein the variable is dc using uncontrolled devices with non-linear characteristics being semiconductor devices using diode- transistor combinations
- G05F3/30—Regulators using the difference between the base-emitter voltages of two bipolar transistors operating at different current densities
Landscapes
- Engineering & Computer Science (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Physics & Mathematics (AREA)
- Power Engineering (AREA)
- Nonlinear Science (AREA)
- Electromagnetism (AREA)
- General Physics & Mathematics (AREA)
- Radar, Positioning & Navigation (AREA)
- Automation & Control Theory (AREA)
- Control Of Electrical Variables (AREA)
Abstract
Description
【発明の詳細な説明】
（イ）技術分野
本発明は、定電流回路に関するもので、特に定電流回路
の出力定電流が温度変化に応じて変化しない様、回路定
数を所定の値に設定した定電流回路を提供せんとするも
のである。[Detailed description of the invention] (a) Technical field The present invention relates to a constant current circuit, and in particular, the circuit constant is set to a predetermined value so that the output constant current of the constant current circuit does not change in response to temperature changes. The purpose is to provide a constant current circuit.
（ロ）技術の背景
ＩＣ（集積回路）においては、定電流回路ｈ″−−多用
ているが、従来の定電流回路（ま、電源電圧ぬ変動に対
しては安定な出力定電流を得ることカー出来る反面、周
囲温度が変化し、定電流回路を！Ｉ４成する回路素子が
温度変化を起すと、そね、に工Ｓシて出力電流が変化し
、定電流性が保てなくなるという欠点を有していた。(b) Background of the technology In ICs (integrated circuits), constant current circuits (h'') are often used, but conventional constant current circuits (well, to obtain a stable output constant current against fluctuations in the power supply voltage) On the other hand, if the ambient temperature changes and the temperature of the circuit elements that make up the constant current circuit changes, the output current will change accordingly, making it impossible to maintain constant current performance. It had
（ハ）発明の要点
本発明は、上述の点に鑑み成されたもので、抵抗（ＲＩ
）トランジスタのペースエミッタ間電圧（Ｖｌｌア）と
に依存する定電流工、を流すこと力１出来る定電流源と
、ダイオード接続され、かつコレクタに前記定電流源が
接続された第１トランジスタと、エミッタに抵抗が接続
され、前記第１トランジスクと電流ミラー関係に接続さ
れた第２トランジスタとから成り、該第２トランジスタ
のコレクタに得らハる出力定電流■２が温度に依存しな
い様、前記抵抗の値Ｒ２を所定値に設定したものである
。(c) Main points of the invention The present invention has been made in view of the above-mentioned points.
) a constant current source that can flow a constant current that depends on the emitter-to-emitter voltage (Vlla) of the transistor; a first transistor that is diode-connected and whose collector is connected to the constant current source; A resistor is connected to the emitter, and the second transistor is connected to the first transistor in a current mirror relationship, and the output constant current (2) obtained at the collector of the second transistor does not depend on the temperature. The resistance value R2 is set to a predetermined value.
（ロ）実施例
Ｗ７１図は、本発明の一実施例を示すもので、（１）は
定電流■、を流すことが出来る定電流源、（２）はコレ
クタが該定電流源（１１に、エミッタが電源（＋ＶｃＣ
）に、ベースがコレクタと共通にそれぞれ接続された第
１トランジスタ、及び（３）はベースが該第１トランジ
スタ（２）のベースに、エミッタが抵抗（４）を介して
前記電源に、コレクタが負荷（５）Ｋそれぞれ接続され
た第２トランジスタである。(B) Example W71 Figure shows an example of the present invention. (1) is a constant current source that can flow a constant current (2), and (2) is a constant current source (11) in which the collector is connected to the constant current source (11). , the emitter is the power supply (+VcC
), a first transistor whose base is commonly connected to the collector, and (3) whose base is connected to the base of the first transistor (2), whose emitter is connected to the power supply via a resistor (4), and whose collector is Loads (5) K are respectively connected second transistors.
しかして、第１図の定電流回路においては、定電流源＜
１）に定電流■、が流れると、該定電流工、は、第１ト
ランジスタ（２）のエミッタに流れ、前記定電流■、と
所定の関係を有する定電流■２が第２トランジスタ（３
）のコレクタから負荷（５）に流れる様に成されている
。Therefore, in the constant current circuit shown in Fig. 1, the constant current source <
When a constant current (2) flows through the first transistor (2), the constant current (2), which has a predetermined relationship with the constant current (2), flows through the second transistor (3).
) flows to the load (5).
いま、定電流源（１）に流れる電流■１を、１１二ふ
・・・・・・ （１）１
（ただし、ＶＢ８はトランジスタのベース・エミッタ間
電圧、Ｒ，は抵抗値）
とし、第１及び第２トランジスタ（２）及び（３）のベ
ース電流を無視すれば、抵抗（４）の両端電圧ぬ、は、
Ｖ−２＝ ＲｔＩｔ ” Ｖｍ＊＋ ＶＩＥ２
・−・・（２１となる、ところで、前記ｖ、ｆｆｉ
＋及びη８２は、それぞれ、
となるから、第（１）乃至第（４）式より、定電流■、
は、 Ｖ
Ｌ −−ｊ−ｌｎ （十１． ） 叫・・（５
）２
となり、第（５）及び（６）式から、
となる。この第（７）式を整理すると、−・・・・ （
７）
となるから、Ｒ２Ｉ２ ＝ ｎＶＴ とおけば、第（
η式は、となる。この第（８）式において、左辺が零と
なる条件は、
であり、結局ｎが
となれば、出力定電流■２は、周囲温度に依存しないも
のとなることは明らかである。従って、最終となる様に
、抵抗（４）の値Ｒ７を選択すれば、第２トランジスタ
（３）のコレクタに得られる定電流■２が抗（４）の温
度係数である。そして、第１図に示される回路を単一の
ＩＣ内に作成した場合には、前記ｎが定数となるので、
前記抵抗（４）の値を設定することにより、出力定電施
工、の設定を簡単に行（・得＝ ２０００ ｐｐｍ７℃
となるので、ｎ＝３．４２となり、例えば１００μへの
出力定電流Ｉ、を得る為には、第０１）式から０．８９
にΩの抵抗（４）を前記第２トランジスタ（３）のエミ
ッタに接続す射ばよいことになる。Now, the current ■1 flowing through the constant current source (1) is 112 times
...... (1) 1 (where VB8 is the voltage between the base and emitter of the transistor, R is the resistance value), and the base currents of the first and second transistors (2) and (3) are ignored. For example, the voltage across resistor (4) is,
V-2= RtIt ” Vm*+ VIE2
...(21, by the way, the above v, ffi
+ and η82 are as follows, so from equations (1) to (4), constant current ■,
, V L --j-ln (11.) Shout...(5
)2, and from equations (5) and (6), it becomes. If we rearrange this equation (7), −・・・・ (
7) Therefore, if we set R2I2 = nVT, the (
The η formula is as follows. In Equation (8), the condition for the left side to be zero is as follows.If n becomes , it is clear that the output constant current 2 becomes independent of the ambient temperature. Therefore, if the value R7 of the resistor (4) is selected so as to be the final value, the constant current 2 obtained at the collector of the second transistor (3) is the temperature coefficient of the resistor (4). When the circuit shown in FIG. 1 is created in a single IC, n becomes a constant, so
By setting the value of the resistor (4), you can easily set the output constant current (gain = 2000 ppm 7℃)
Therefore, n = 3.42. For example, in order to obtain the output constant current I for 100μ, 0.89 from equation 01)
It is only necessary to connect a resistor (4) of Ω to the emitter of the second transistor (3).
第２図は、第１図における定電流源（１）を具体回連で
示した本発明の別の実施例を示すもので、定電流源（１
）を、ベース・コレクタ間が短絡されてダイオード接続
と成された第３トランジスタ（６）と、該第３トランジ
スタ（６）と電流ミラー関係に接続された第４トランジ
スタ（７）と、第１及び第２分圧抵抗（８）及び（９）
と、該第１及び第２分圧抵抗（８）及び（９）の分圧点
を定電圧とする為の第１及び第２ダイオードＧＯ）及び
（１１）とによって構成したものである。しかして、第
２分圧抵抗（９）の値をＲ１とすれば、該抵抗（９）に
流れる電流Ｉ、は、
■。FIG. 2 shows another embodiment of the present invention in which the constant current source (1) shown in FIG.
), a third transistor (6) whose base and collector are short-circuited to form a diode connection, a fourth transistor (7) connected to the third transistor (6) in a current mirror relationship, and a first and second voltage dividing resistors (8) and (9)
and first and second diodes GO) and (11) for making the voltage dividing points of the first and second voltage dividing resistors (8) and (9) a constant voltage. Therefore, if the value of the second voltage dividing resistor (9) is R1, the current I flowing through the resistor (9) is: (2).
バー＝ Ｒ＋Ｌ ＋ Ｖ−、” Ｌ ＝ ・・・（
１２１−垢一
となり、第３及び第４トランジスタ（６）及び（力は電
流ミラー関係にあるから、前記第４トランジスタ（力の
コレクタ電流もＩ、となり、結局、第１図の定電流源（
１）の条件を満す定電流回路が構成出来る。Bar=R+L+V-,"L=...(
Since the third and fourth transistors (6) and (force are in a current mirror relationship, the collector current of the fourth transistor (force) is also I, and as a result, the constant current source (
A constant current circuit that satisfies the condition 1) can be constructed.
となり、この第ａ■式を図示すると第３図の如くなる。When this equation (a) is illustrated, it becomes as shown in FIG. 3.
しかして、第３図からｎ＝３．４２とすれば、る。また
、ｎ＝３．４２の近傍すなわち、２．５ （ｎく５程度
の範囲でも、出力定電流Ｉ２の温度係数は、±３ｏ ｏ
ｐｐｍ／℃程度と極めて小さく、略温度に依存しない
定電流を発生することが出来る。従って、本発明は、温
度に依存しない定電流を発生するという本発明の主旨に
基き、出力定電流■２の温度係数が零となる抵抗値ばか
りでなく、その近傍の値を選択し得ることは勿論である
。Therefore, if n=3.42 from FIG. In addition, in the vicinity of n=3.42, that is, in the range of about 2.5 (n), the temperature coefficient of the output constant current I2 is ±3o o
It is possible to generate a constant current that is extremely small, on the order of ppm/°C, and is substantially independent of temperature. Therefore, based on the gist of the present invention to generate a constant current that does not depend on temperature, the present invention makes it possible to select not only a resistance value at which the temperature coefficient of output constant current (2) becomes zero, but also a value in the vicinity thereof. Of course.
（ホ）効果
以上述べた如く、本発明に依れば、温度に依存しない定
電流を得ることが出来るので、特に熱的に均一性を保つ
ことの出来るＩＣ内に−おける定電流回路に応用して効
果の高いものである。(e) Effects As mentioned above, according to the present invention, it is possible to obtain a constant current that is independent of temperature, so it is particularly applicable to constant current circuits in ICs that can maintain thermal uniformity. It is highly effective.
第１図は本発明の一実施例を示す回路図、第２図は本発
明の別の実施例を示す回路図、及び第３図は本発明の説
明に供する為の特性図であろう主な図番の説明
（１）・・・定電流源、 （２）・・・第１トランジス
タ、（３）・・・第２トランジスタ、 （４）・・・抵
抗。
第１図
十Ｖｃｃ
第２図 十ＶＣＣFig. 1 is a circuit diagram showing one embodiment of the present invention, Fig. 2 is a circuit diagram showing another embodiment of the invention, and Fig. 3 is a characteristic diagram for explaining the present invention. Explanation of figure numbers: (1) Constant current source, (2) First transistor, (3) Second transistor, (4) Resistor. Fig. 1 10Vcc Fig. 2 10VCC
Claims (1)
に、コレクタが定電流源に接続された第１トランジスタ
と、ベースが該第１トランジスタのベースに、エミッタ
が抵抗を介して前記電源に接続された第２トランジスタ
とを備え、前記定電流前記抵抗の値Ｒ２を定め、前記第
２トランジスタのコレクタに得られる定電流Ｉ２が温度
に依存しない様にしたことを特徴とする定電流回路。（
ただし、ＶＩｌ！＋はトランジスタのペース・エミッタ
間電圧で、α（ＶＢｖ）はその温度係数、Ｒ１は抵抗値
で、α（Ｒ１）はその温度係数、ＶＴ（−一に工；には
、ボルツマン定数、Ｔは絶対温度、ｑは電子の電荷）は
熱電圧で、α（′ｖｒ）はその温度係数、α（Ｒ２）は
抵抗値Ｒ２の抵抗の温度係数である。）(1) A first transistor whose pace and collector are short-circuited, whose emitter is connected to a power source and whose collector is connected to a constant current source, whose base is connected to the base of the first transistor and whose emitter is connected to the power source via a resistor. 2. A constant current circuit, characterized in that the constant current I2 is determined to be a value R2 of the resistor so that the constant current I2 obtained at the collector of the second transistor does not depend on temperature. (
However, VIl! + is the voltage between the transistor's pace and emitter, α (VBv) is its temperature coefficient, R1 is the resistance value, α (R1) is its temperature coefficient, VT (-1) is the Boltzmann constant, and T is the Absolute temperature, q is the electron charge) is the thermal voltage, α('vr) is its temperature coefficient, and α(R2) is the temperature coefficient of resistance of resistance value R2. )
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19102982A JPS5979322A (en) | 1982-10-29 | 1982-10-29 | Constant current circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19102982A JPS5979322A (en) | 1982-10-29 | 1982-10-29 | Constant current circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5979322A true JPS5979322A (en) | 1984-05-08 |
| JPH0551926B2 JPH0551926B2 (en) | 1993-08-04 |
Family
ID=16267706
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP19102982A Granted JPS5979322A (en) | 1982-10-29 | 1982-10-29 | Constant current circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5979322A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010152566A (en) * | 2008-12-24 | 2010-07-08 | Fujitsu Semiconductor Ltd | Current producing circuit, current producing method and electronic device |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5320554A (en) * | 1976-08-11 | 1978-02-24 | Hitachi Ltd | Constant current circuit |
-
1982
- 1982-10-29 JP JP19102982A patent/JPS5979322A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5320554A (en) * | 1976-08-11 | 1978-02-24 | Hitachi Ltd | Constant current circuit |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010152566A (en) * | 2008-12-24 | 2010-07-08 | Fujitsu Semiconductor Ltd | Current producing circuit, current producing method and electronic device |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0551926B2 (en) | 1993-08-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP2682470B2 (en) | Reference current circuit | |
| KR0136121B1 (en) | Overheat detecting circuit | |
| JPH02285408A (en) | Band gap voltage reference with advanced temperature correction | |
| JPH08321732A (en) | Current mirror circuit and reference current circuit | |
| JP2001510609A (en) | Reference voltage source with temperature compensated output reference voltage | |
| JPH05727B2 (en) | ||
| US20120153997A1 (en) | Circuit for Generating a Reference Voltage Under a Low Power Supply Voltage | |
| JPS5979322A (en) | Constant current circuit | |
| JPH05216550A (en) | Voltage generator | |
| JPH05204480A (en) | Constant voltage circuit | |
| JP2748414B2 (en) | Voltage source circuit | |
| JP2729001B2 (en) | Reference voltage generation circuit | |
| JPS5819083B2 (en) | constant current circuit | |
| JP4163861B2 (en) | Semiconductor device | |
| JPH0820915B2 (en) | Constant current circuit | |
| JPS5834493Y2 (en) | DC constant voltage power supply circuit | |
| US9588538B2 (en) | Reference voltage generation circuit | |
| JP3437274B2 (en) | Reference voltage circuit | |
| JPH0789304B2 (en) | Reference voltage circuit | |
| JPS59144209A (en) | Offset voltage trimming circuit of operational amplifier | |
| JPS63258109A (en) | Reference current source | |
| JPH1195850A (en) | Constant voltage generation circuit | |
| JPH07121256A (en) | Current mirror circuit | |
| JPH07183737A (en) | Current source circuit | |
| JPS63236403A (en) | Current source circuit |