EP0205539A1 - Active circuit element - Google Patents

Active circuit element

Info

Publication number
EP0205539A1
EP0205539A1 EP19860900233 EP86900233A EP0205539A1 EP 0205539 A1 EP0205539 A1 EP 0205539A1 EP 19860900233 EP19860900233 EP 19860900233 EP 86900233 A EP86900233 A EP 86900233A EP 0205539 A1 EP0205539 A1 EP 0205539A1
Authority
EP
European Patent Office
Prior art keywords
transistor
emitter
terminal
circuit element
transistors
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.)
Withdrawn
Application number
EP19860900233
Other languages
German (de)
French (fr)
Inventor
Gábor HUSZTI
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Licencia Talalmanyokat Ertekesito Es Innovacios Kuelkereskedelmi Vallalat
Licencia Talalmanyokat Ertekesito Vallalat
Original Assignee
Licencia Talalmanyokat Ertekesito Es Innovacios Kuelkereskedelmi Vallalat
Licencia Talalmanyokat Ertekesito Vallalat
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Licencia Talalmanyokat Ertekesito Es Innovacios Kuelkereskedelmi Vallalat, Licencia Talalmanyokat Ertekesito Vallalat filed Critical Licencia Talalmanyokat Ertekesito Es Innovacios Kuelkereskedelmi Vallalat
Publication of EP0205539A1 publication Critical patent/EP0205539A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03K—PULSE TECHNIQUE
    • H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
    • H03K17/14—Modifications for compensating variations of physical values, e.g. of temperature
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03F—AMPLIFIERS
    • H03F3/00—Amplifiers with only discharge tubes or only semiconductor devices as amplifying elements
    • H03F3/34—DC amplifiers in which all stages are DC-coupled
    • H03F3/343—DC amplifiers in which all stages are DC-coupled with semiconductor devices only

Definitions

  • the invention relates to an active circuit element constituting a transistor comprising a basis terminal, an emitter terminal and a collector terminal.
  • the proposed active circuit element is characterized by a linear characteristics: the output current is a linear function of the input voltage.
  • the known active circuit elements are characterized by the fact that their output current changes in a nonlinear way with the input voltage.
  • An example of the known devices forming the art in the field of the active elements is the bipolar transistor having exponential characteristics, the field--effect transistor showing a quadratic characteristics etc.
  • the nonlinear characteristics is in most cases disadvantageous and is the source of generating harmonic frequency signals of relatively high level.
  • the effects of the nonlinear characteristics can be diminished by applying negative feedback.
  • the networks comprising negative feedback loops are not satisfactory under aspect of the transient processes.
  • Another disadvantage of the known devices should be seen in strong temperature dependency of the characteristics: at different temperatures the same input voltage results in different outpuit currents. This disadvantageous feature can be avoided by application of compensating circuits especially in case of high
  • the object of the invention is to create an active circuit element having linear characteristics.
  • the invention is based on the recognition that the known bipolar transistors can form a desired active circuit element when connected to each other as shown herebelow.
  • the proposed active circuit element constituting a transistor comprising a basis terminal, an emitter terminal and a collector terminal Is a device comprising four transistors, the first, the third and the fourth of them being of type opposite to the type of the second transistor, wherein the basis of the first transistor constitutes the basis terminal, the emitter of the second transistor is con nected to the emitter terminal and the third and fourth transistors are connected via their respective emitters to the collector terminal, further the third transistor is connected through its basis to the basis and the collector of the fourth transistor and over its collector to the emitter of first transistor and to the basis ⁇ f the second transistor, wherein the collector of the first transistor is connected to the emitter of the second transistor.
  • the type of the second transistor is the type of the proposed active circuit element which is - it will be described in more detail - a pnp-type element when the first, third and fourth transistors are of npn-type and vice versa.
  • the proposed active circuit element constitutes a transistor-type device having a linear characteristics without or with very low level of dependency on temperature, of harmonic distorsion, ensuring output current following the input voltage according to a linear function.
  • the active circuit element according to the invention comprises a basis terminal 1, an emitter terminal 2 and a collector terminal 3 with four transistors thereamong.
  • a first transistor 4 is coupled through its basis to the basis terminal 1, through its collector to the emitter of a second transistor 5 and through its emitter to the basis of the second transistor 5 and to the collector of a third transistor 6.
  • the basis of the third transistor 6 is coupled to the basis and the collector of a fourth transistor 8 forming thereby a diode.
  • the voltage drop on this fourth transistor 8 ensures the input voltage of the third transistor 6.
  • the emitter of the third transistor 6 is connected with the emitter of the fourth transistor 8 and their common point is connected to the collector terminal 3.
  • the common point of the emitter of the first transistor 4 and of the collector of the second transistor 5 form the emitter terminal 2, wherein a resistor 9 can be included between the mentioned common point and the emitter terminal 2.
  • the first, third and fourth transistors 4, 6 and 8 are of the same type, e.g. npn-type oppositely to the type of the second transistor, e.g. pnp-type, wherein the type of the second transistor 5 determines the transistor type of the active circuit element proposed by the invention.
  • the active circuit element according to the invention can be connected in an outer circuit by applying input voltage U be between a terminal 11 and the basis terminal 1 obtaining thereby output current I ki flowing be tween a terminal 12 and the collector terminal 3 through an outer resistor 10. Between the terminal 12 and the terminal 13 a supply voltage U tap is applied. The terminals 11 and 13 are common and they are connected to a pole of the resistor 9. In normal operating conditions the input voltage U be is an alternating voltage supervening a direct voltage, the supply voltage U tap is a direct voltage and the output current I ki is an alternating current supervening a direct current.
  • the operated active circuit element according to the Invention works in the following way, wittcut taking into account the basis currents of the transistors.
  • the voltage U 2 of the emitter terminal 2 can be determined as
  • U 2 U be + U BE4 - U BE5 , wherein U BE is the basis-emitter voltage of the first and second transistors 4 and 5 and U be is the input voltage applied between the terminal 11 and the basis terminal 1.
  • U 2 U be + K (7) i.e. the voltage of the emitter terminal 2 is equal to the input voltage shifted by a constant level signed by K in the expressions given above.
  • I ki I 5 + I 4 and this is even the current flowing through the resistor 9, which can be signed by I R9 .
  • R is the resistance of the resistor 9.
  • the output current I ki is a linear function of the input, voltage U be and the slope characterizing this linear function is 1/R, i.e. the reciprocal value of the resistance R.
  • K/R is a constant value, of course.
  • thermic dependency of the values characterizing the transistors is the same for all of the mentioned transistors and therefore it has no influence on the thermic behaviour of the active circuit element of the invention.
  • the proposed circuit element in integrated form shows a very low level of thermic sensitivity.
  • the proposed active circuit element can be applied in every case when linear signal transmission and amplification is required what can be done without feedback and thermic problems.
  • the circuits realised on the basis of the proposed element comprise less elements, show higher linea rity and lower level of transient errors than the circuits realised on the basis of the elements known up to date.
  • the proposed circuit element can be produced by well known technological processes of integrating or by simple interconnecting transistors of appropriate types, e.g. bipolar transistors. Its most important advantage is the linearity of the characteristics.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Amplifiers (AREA)

Abstract

Elément actif de circuit, constitué d'un transistor comprenant un terminal de base (1), un terminal d'émetteur (2) et un terminal collecteur (3). L'élément actif de circuit ci-décrit se caractérise par le fait qu'il comprend quatre transistors dont le premier, le troisième et le quatrième (4, 6, 8) sont de type opposé à celui du deuxième transistor (5) et la base du premier transistor (4) constitue le terminal de base (1), l'émetteur du deuxième transistor (5) est relié au terminal d'émetteur (2) et le troisième et quatrième transistors (8) sont reliés par leurs émetteurs respectifs au terminal de collecteur (3), le troisième transistor (6) est relié par la base à la base et au collecteur du quatrième transistor (8) et par son collecteur à l'émetteur du premier transistor (4) et à la base du deuxième transistor (5), le collecteur du premier transistor (4) étant relié à l'émetteur du deuxième transistor (5).Active circuit element, consisting of a transistor comprising a base terminal (1), an emitter terminal (2) and a collector terminal (3). The active circuit element described below is characterized by the fact that it comprises four transistors of which the first, third and fourth (4, 6, 8) are of the opposite type to that of the second transistor (5) and the base of the first transistor (4) constitutes the base terminal (1), the emitter of the second transistor (5) is connected to the emitter terminal (2) and the third and fourth transistors (8) are connected by their respective emitters at the collector terminal (3), the third transistor (6) is connected by the base to the base and to the collector of the fourth transistor (8) and by its collector to the emitter of the first transistor (4) and to the base of the second transistor (5), the collector of the first transistor (4) being connected to the emitter of the second transistor (5).

Description

ACTIVE CIRCUIT ELEMENT
The invention relates to an active circuit element constituting a transistor comprising a basis terminal, an emitter terminal and a collector terminal. The proposed active circuit element is characterized by a linear characteristics: the output current is a linear function of the input voltage. The known active circuit elements are characterized by the fact that their output current changes in a nonlinear way with the input voltage. An example of the known devices forming the art in the field of the active elements is the bipolar transistor having exponential characteristics, the field--effect transistor showing a quadratic characteristics etc. The nonlinear characteristics is in most cases disadvantageous and is the source of generating harmonic frequency signals of relatively high level. The effects of the nonlinear characteristics can be diminished by applying negative feedback. The networks comprising negative feedback loops are not satisfactory under aspect of the transient processes. Another disadvantage of the known devices should be seen in strong temperature dependency of the characteristics: at different temperatures the same input voltage results in different outpuit currents. This disadvantageous feature can be avoided by application of compensating circuits especially in case of high currents.
The technical development requires active circuit elements with theoretically unlimited input voltage - output current characteristics wherein an outer resistor can make the characteristics be linear with slope determined by the reciprocal value of an outer resistor connected to one of the terminals of the circuit element. This device can be called linear transistor, which is thermally compensated and thereby shows a theoretical independency of the characteristics on the temperature.
Hence, the object of the invention is to create an active circuit element having linear characteristics. The invention is based on the recognition that the known bipolar transistors can form a desired active circuit element when connected to each other as shown herebelow.
The recognition mentioned above means that subtracting the basis-emitter voltage of two bipolar transistor from one another and ensuring a linear coupling between the collector currents of the two transistors it can be achieved that the difference of the basis-emitter voltages of the transistors remains constant during the work of the transistors. By realising a low heat resistance heat flow path between the two transistors, e.g. by integrating them in a common chip the temperature dependency of their P - N junctions is the same.
The proposed active circuit element constituting a transistor comprising a basis terminal, an emitter terminal and a collector terminal Is a device comprising four transistors, the first, the third and the fourth of them being of type opposite to the type of the second transistor, wherein the basis of the first transistor constitutes the basis terminal, the emitter of the second transistor is con nected to the emitter terminal and the third and fourth transistors are connected via their respective emitters to the collector terminal, further the third transistor is connected through its basis to the basis and the collector of the fourth transistor and over its collector to the emitter of first transistor and to the basis σf the second transistor, wherein the collector of the first transistor is connected to the emitter of the second transistor.
It is advantageous to Integrate the transistors in a common chip together with a resistor between the emitter and the second transistor and the emitter terminal, whereby the slope of the characteristics can be adjusted.
The type of the second transistor is the type of the proposed active circuit element which is - it will be described in more detail - a pnp-type element when the first, third and fourth transistors are of npn-type and vice versa. The proposed active circuit element constitutes a transistor-type device having a linear characteristics without or with very low level of dependency on temperature, of harmonic distorsion, ensuring output current following the input voltage according to a linear function.
The invention will be now described in more detail with reference to the accompanying drawings, wherein the single Figure shows the proposed circuit element connected to some terminals offan outer operating circuit.
The active circuit element according to the invention (Figure) comprises a basis terminal 1, an emitter terminal 2 and a collector terminal 3 with four transistors thereamong. A first transistor 4 is coupled through its basis to the basis terminal 1, through its collector to the emitter of a second transistor 5 and through its emitter to the basis of the second transistor 5 and to the collector of a third transistor 6. The basis of the third transistor 6 is coupled to the basis and the collector of a fourth transistor 8 forming thereby a diode. The voltage drop on this fourth transistor 8 ensures the input voltage of the third transistor 6. The emitter of the third transistor 6 is connected with the emitter of the fourth transistor 8 and their common point is connected to the collector terminal 3. The common point of the emitter of the first transistor 4 and of the collector of the second transistor 5 form the emitter terminal 2, wherein a resistor 9 can be included between the mentioned common point and the emitter terminal 2.
The first, third and fourth transistors 4, 6 and 8 are of the same type, e.g. npn-type oppositely to the type of the second transistor, e.g. pnp-type, wherein the type of the second transistor 5 determines the transistor type of the active circuit element proposed by the invention.
It is important that the forward voltages of the first and second transistors 4 and 5 show a constant difference; this requires the same values of their emitter currents realised by the third and the fourth transistors 6 and 8 wherein a current should be driven through the first transistor 4 which has the same intensity as the current flowing over the second transistor 5.
As shown in the Figure, the active circuit element according to the invention can be connected in an outer circuit by applying input voltage Ube between a terminal 11 and the basis terminal 1 obtaining thereby output current Iki flowing be tween a terminal 12 and the collector terminal 3 through an outer resistor 10. Between the terminal 12 and the terminal 13 a supply voltage Utap is applied. The terminals 11 and 13 are common and they are connected to a pole of the resistor 9. In normal operating conditions the input voltage Ube is an alternating voltage supervening a direct voltage, the supply voltage Utap is a direct voltage and the output current Iki is an alternating current supervening a direct current. When applying the operated active circuit element according to the Invention works in the following way, wittcut taking into account the basis currents of the transistors.
The voltage U2 of the emitter terminal 2 can be determined as
U2 = Ube + UBE4 - UBE5 , wherein UBE is the basis-emitter voltage of the first and second transistors 4 and 5 and Ube is the input voltage applied between the terminal 11 and the basis terminal 1.
The basis-emitter voltage of a transistor depends on a specific thermic potential T, on the collector current I and a constant value IO characterizing the transistor. It can be expressed by the function UBE = Tlnl/IO. Therefore the voltage U2 is
wherein 4 and 5 are indices relating to the first and second transistors 4 and 5. The third and the fourth transistors are connected in a way as to ensure the equality of their basis-emitter voltage. This means that UBE6 = UBE8. Therefore
The interconnection of the transistors in the active circuit element of the invention ensures that I4=I6 (3)
I5 = I8 (4)
(in the above expressions the indices 4, 5, 6, 8 relate to the corresponding transistor shown in the Figure).
Replacing in (1) the appropriate items by the expressions (2), (3) and (4) it follows that
wherein
The conclusion is that according to (5)
U2 = Ube + K (7) i.e. the voltage of the emitter terminal 2 is equal to the input voltage shifted by a constant level signed by K in the expressions given above.
The output current flowing between the terminal 12 and the collector terminal 3 through the outer resistor 10 can be expressed in the following form: Iki = I8 + I6 Because of (3) and (4)
Iki = I5 + I4 and this is even the current flowing through the resistor 9, which can be signed by IR9. According to the general laws
Hence,
wherein R is the resistance of the resistor 9. This means that the output current Iki is a linear function of the input, voltage Ube and the slope characterizing this linear function is 1/R, i.e. the reciprocal value of the resistance R. In (8) K/R is a constant value, of course.
When the transistors 4, 5, 6 and 8 and eventually the resistor 9 are integrated in a chip the thermic dependency of the values characterizing the transistors is the same for all of the mentioned transistors and therefore it has no influence on the thermic behaviour of the active circuit element of the invention. This means, the proposed circuit element in integrated form shows a very low level of thermic sensitivity.
The proposed active circuit element can be applied in every case when linear signal transmission and amplification is required what can be done without feedback and thermic problems. The circuits realised on the basis of the proposed element comprise less elements, show higher linea rity and lower level of transient errors than the circuits realised on the basis of the elements known up to date. The proposed circuit element can be produced by well known technological processes of integrating or by simple interconnecting transistors of appropriate types, e.g. bipolar transistors. Its most important advantage is the linearity of the characteristics.

Claims

1. Active circuit element, constituting a transistor comprising a basis terminal, an emitter terminal and a collector terminal c h a r a c t e r i z e d in comprising four transistors wherein the first, the third and the fourth (6, 4, 8) are of type opposite to the type of the second transistor (5) and the basis of the first transistor (4) constitutes the basis terminal (1), the emitter of the second transistor (5) is connected to the emitter terminal (2) and the third and fourth transistors (8) are connected with their respectives to the collector terminal (3), further the third transistor (6) is connected through its basis to the bais and the collector of the forth transistor (8) and over its collector to the emitter of the first transistor (4) and to the basis of the second transistor
(5), wherein the collector of the first transistor (4) is connected to the emitter of the second transistor (5).
2. An active circuit element as claimed in claim 1, c h a r a c t e r i z e d in comprising a resistor (9) between the emitter of the second transistor (5) and the emitter terminal (2).
3. An active circuit element as claimed in claim 1 or 2, c h a r a c t e r i z e d in comprising three transistors of pnp-type.
4. An active circuit element as claimed in claim 1 or 2, c h a r a c t e r i z e d in comprising three transistors of npn-type.
5. An active circuit element as claimed in any preceding claim, c h a r a c t e r i z e d in forming by the transistors (4, 5, 6, 8) and their connection an integrated circuit.
6. An active circuit element as claimed in claim 5, c h a r a c t e r i z e d in comprising a resistor (9) integrated between the emitter point of the second transistor (5) and the emitter terminal (2).
EP19860900233 1984-12-29 1985-12-29 Active circuit element Withdrawn EP0205539A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
HU488884 1984-12-29
HU488884 1984-12-29

Publications (1)

Publication Number Publication Date
EP0205539A1 true EP0205539A1 (en) 1986-12-30

Family

ID=10969155

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19860900233 Withdrawn EP0205539A1 (en) 1984-12-29 1985-12-29 Active circuit element

Country Status (3)

Country Link
EP (1) EP0205539A1 (en)
AU (1) AU5308486A (en)
WO (1) WO1986004196A1 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4961046A (en) * 1988-08-19 1990-10-02 U.S. Philips Corp. Voltage-to-current converter
GB9617323D0 (en) * 1996-08-17 1996-09-25 Belyi Valerie High gain, wide band amplifier

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3641450A (en) * 1970-12-15 1972-02-08 Motorola Inc Gain controlled differential amplifier circuit
US3924202A (en) * 1974-08-21 1975-12-02 Rca Corp Electronic oscillator
US4063149A (en) * 1975-02-24 1977-12-13 Rca Corporation Current regulating circuits
US4063116A (en) * 1976-08-26 1977-12-13 Raytheon Company Temperature compensated current source
GB2030765B (en) * 1978-10-02 1983-04-27 Lumenition Ltd Darlington transistor pairs
DE2939917A1 (en) * 1979-10-02 1981-04-16 Philips Patentverwaltung Gmbh, 2000 Hamburg MAGNETICALLY CONTROLLABLE, ELECTRONIC SWITCH
CH648434A5 (en) * 1982-04-23 1985-03-15 Centre Electron Horloger SEMICONDUCTOR DEVICE HAVING AN OPERATING CHARACTERISTIC OF A BIPOLAR TRANSISTOR AND M0S CIRCUIT INCORPORATING SUCH A DEVICE.

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO8604196A1 *

Also Published As

Publication number Publication date
AU5308486A (en) 1986-07-29
WO1986004196A1 (en) 1986-07-17

Similar Documents

Publication Publication Date Title
EP0115593B1 (en) Photo transducer circuit
EP0072589B1 (en) Current stabilizing arrangement
US4329639A (en) Low voltage current mirror
EP0219682B1 (en) A current to voltage converter circuit
US4065725A (en) Gain control circuit
US4379268A (en) Differential amplifier circuit
US4119869A (en) Constant current circuit
GB2236444A (en) Current mirror
EP0544360A2 (en) Reference current loop
JP2869664B2 (en) Current amplifier
EP0155039B1 (en) Current-source arrangement
US4329598A (en) Bias generator
US4473793A (en) Bias generator
EP0061705B1 (en) Low-value current source circuit
EP0157447B1 (en) Differential amplifier
EP0205539A1 (en) Active circuit element
EP0110720B1 (en) Current mirror circuit
EP0264563B1 (en) Voltage regulator having a precision thermal current source
EP0620513B1 (en) Balanced voltage-to-current converter with quiescent current control
US4899064A (en) Absolute value differential amplifier
JPS6154286B2 (en)
US5534813A (en) Anti-logarithmic converter with temperature compensation
EP0104950B1 (en) A differential amplifier circuit
EP0481277B1 (en) Current source
EP0418025A2 (en) Current mirror having large current scaling factor

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH DE FR GB IT LI LU NL SE

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 19860930

RIN1 Information on inventor provided before grant (corrected)

Inventor name: HUSZTI, GABOR