RU2677401C1 - Bipolar-field buffer amplifier - Google Patents

Abstract

FIELD: radio equipment.SUBSTANCE: invention relates to the field of radio engineering and communications and can be used as an output stage for amplifying fast-changing analog signals in power (buffer amplifier – BA), in the structure of analog microcircuits for various functional purposes, for example, operational amplifiers. BA contains first 1 field-effect transistor, second 3 field-effect transistor, output bipolar transistor 5, first 8 current-stabilizing two-terminal, additional current mirror 9, consistent with first 4 bus power supply, and the output of current mirror 9 is connected to the base of transistor 5 and is connected to the gate of second 3 field-effect transistor. Presence of a common negative feedback with respect to output 6 ensures high linearity of the amplitude pass characteristic.EFFECT: increase in the maximum slew rate of the output voltage and a decrease in the transient establishment time in the BA with large pulsed input signals (measured with the supply voltage).1 cl, 4 dwg

Description

The invention relates to the field of analog microelectronics can be used as BiJFet (bipolar-field) buffer amplifiers of various analog devices that can work under conditions of penetrating radiation and low temperatures.

A significant number of buffer amplifier circuits (BU) are known, which are implemented on bipolar (BJT) and field (BiJFet, CMOS, SOI, SSC, etc.) transistors, as well as when they are turned on jointly [1-27]. In many cases, the control unit scheme is adapted to specific technological processes and external factors, for example, the effect of low temperatures and radiation, because only in this case is the implementation of the limiting parameters of the control unit provided.

Microcircuits based on the BiJFet technological process have proven themselves to work in harsh operating conditions (exposure to low, including cryogenic temperatures, neutron flux, accumulated radiation dose, gamma rays, etc.) [28]. However, this technological process does not provide satisfactory operation of analog microcircuits using pnp transistors in their signal circuits [28]. In this regard, for example, in BiJFet operational amplifiers (op amps), it is recommended to primarily use only field effect transistors with a control
pn junction and bipolar npn transistors [28]. This imposes significant restrictions on the applied circuitry of the output stages of analogue circuits of this class.

In modern electronic equipment, buffer amplifiers implemented as source repeaters on BiJFet or CMOS transistors are used [1-27]. Push-pull output stages are also known only on CMOS transistors with p- or n-channels
[22-25]. In some cases, push-pull output stages are performed on input CMOS transistors and output bipolar transistors [26]. Due to its simplicity, the abovementioned circuitry solutions are most popular both in foreign and in Russian analog microcircuits, implemented on the basis of standard technological processes.

The closest prototype (Fig. 1) of the claimed device is a buffer amplifier based on output complementary bipolar transistors according to patent RU No. 2.523.947, fig. 4. It contains (Fig. 1) a first 1 field-effect transistor, the gate of which is connected to the input of device 2, a second 3 field-effect transistor, the drain of which is connected to the first 4 bus of the power supply, an output bipolar transistor 5, the emitter of which is connected to the output of the device 6, the base is connected to the second 7 bus of the power supply through the first 8 current-stabilizing bipolar, and the collector of the output bipolar transistor 5 is connected to the second 7 bus of the power source.

A significant drawback of the known buffer amplifier is that due to the limitations of the BiJFet technological process, for example, 3KBT of OJSC Integral (Minsk), it is not recommended to use p-n-p transistors in it at low temperatures. Thus, the scheme of the control unit prototype has limited use.

The main objective of the proposed invention is to create a radiation-resistant and low-temperature circuitry solution for a BiJFet process that does not contain pnp transistors (for example, based on the base matrix crystals ABMK-1.3, ABMK-1.7, ABMK-2.1, etc.), providing a push-pull conversion of input voltage (class AB mode) with high linearity of the passage characteristic, low input current and high input differential resistance.

The problem is achieved in that in the bipolar field buffer amplifier of FIG. 1, containing the first 1 field-effect transistor, the gate of which is connected to the input of device 2, the second 3 field-effect transistor, the drain of which is connected to the first 4 bus of the power supply, the output bipolar transistor 5, the emitter of which is connected to the output of the device 6, the base is connected to the second 7 bus the power source through the first 8 current-stabilizing bipolar, and the collector of the output bipolar transistor 5 is connected to the second 7 bus of the power source, new elements and communications are provided - the source of the first 1 field-effect transistor is connected to the output of the device 6 and the source of the second 3 field-effect transistor, the drain of the first 1 field-effect transistor is connected to the input of an additional current mirror 9, matched with the first 4 bus of the power source, and the output of the additional current mirror 9 is connected to the base of the output bipolar transistor 5 and connected to the gate of the second 3 field effect transistor.

In the drawing of FIG. 1 shows a diagram of a control unit prototype, and in the drawing of FIG. 2 is a diagram of the inventive device.

In the drawing of FIG. 3 shows a diagram of the inventive control unit of FIG. 2 in the environment PSpice on radiation-dependent and low-temperature models of transistors of the base matrix crystal ABMK_1.7 (OJSC Integral, Minsk) [28].

In the drawing of FIG. 4 shows the amplitude characteristic of the BiJFet control unit (Fig. 3) at a current of I1 = 300 μA and different load resistances
R _n = R _var = 1 kOhm, R _n = R _var = 2 kOhm, R _n = R _var = 10 kOhm (PADJ transistor models are high current).

The output stage of the BiJFet (bipolar field) operational amplifier of FIG. 2 contains the first 1 field-effect transistor, the gate of which is connected to the input of device 2, the second 3 field-effect transistor, the drain of which is connected to the first 4 bus of the power source, the output bipolar transistor 5, the emitter of which is connected to the output of the device 6, the base is connected to the second 7 bus of the source power supply through the first 8 current-stabilizing bipolar, and the collector of the output bipolar transistor 5 is connected to the second 7 bus power source. In the circuit of FIG. 2, the source of the first 1 field-effect transistor is connected to the output of the device 6 and the source of the second 3 field-effect transistor, the drain of the first 1 field-effect transistor is connected to the input of the additional current mirror 9, which is matched with the first 4 bus of the power source, and the output of the additional current mirror 9 is connected to the base of the output bipolar transistor 5 and is connected to the gate of the second 3 field-effect transistor. The output of the device 6 is connected to the load 10.

Consider the operation of the proposed control unit of FIG. 2

In the static mode (R _n = R _var = ∞, U _I = 0) at a unit current transfer coefficient of the additional current mirror 9 (K _i = 1), the following currents are set in the circuit

(1)

(one)

– ток истока первого 1 полевого транзистора;

– ток истока второго 3 полевого транзистора при напряжении затвор-исток

;Where

- source current of the first 1 field-effect transistor;

- source current of the second 3 field-effect transistor with a gate-source voltage

;

– ток эмиттера выходного биполярного транзистора 5.

- current emitter of the output bipolar transistor 5.

, то в нагрузке 10 образуется выходной ток

, максимальное значение которого определяется формулойIf a positive input voltage is applied to the input of the control unit

then an output current is generated in load 10

whose maximum value is determined by the formula

, (2)

, (2)

– коэффициент передачи по току базы выходного биполярного транзистора 5;

– ток первого 8 токостабилизирующего двухполюсника.Where

- current transfer coefficient of the base of the output bipolar transistor 5;

- current of the first 8 current-stabilizing two-terminal network.

) и, следовательно, приращение выходного напряжения в данном режиме БУ соответствует приращению его входного напряжения. Как следствие, максимальный отрицательный ток в нагрузке 10 будет определяться максимальным током стока полевого транзистора 3. With a negative increment of the input voltage of the control unit, the load current is provided by the second 3 field-effect transistor. In this case, the source current of the first 1 field-effect transistor does not change (

) and, therefore, the increment of the output voltage in this mode of the control unit corresponds to the increment of its input voltage. As a result, the maximum negative current in the load 10 will be determined by the maximum drain current of the field effect transistor 3.

A feature of the proposed control unit circuit is the presence of a general negative feedback with respect to output 6, which ensures high linearity of the amplitude pass characteristic of FIG. four.

In some cases, an additional p-n junction can occur at the source of the second 3 field-effect transistor, which reduces the static current of this active element.

Computer simulation (Fig. 4) shows that the proposed buffer amplifier, the circuitry of which is adapted for use in the low temperature range and the influence of penetrating radiation [28], has significant advantages in comparison with the well-known options for constructing controllers when they are implemented within the framework of the BiJFet technological process.

BIBLIOGRAPHIC LIST

1. Patent RU No. 2.523.947 fig. four

2. WO 2007135139

3. US 4743862

4. US 6433638, fig. 1a-2

5. US 20050253653

6. US 4825174, fig. 3, fig. 6

7. RU 2099856, fig. 3

8. US 4,904,953, fig. 2

9. US 7896339, fig. four

10. US 6342814

11. US 2010/0182086

12. US 5387880, fig. one

13. US 4,598,253

14. US 4,667,165, fig. 2

15. US 4,596,958

16. US 7116172, fig. 4, fig. 5

17. US 5648743

18. US 5367271, fig. 2

19. US 2000/0112075, fig. 3

20. US 5065043, fig. 1f

21. Horowitz P., Hill W. The art of circuitry: Per. from English - Ed. 2nd. - M.: Publishing house BINOM. 2014 .-- 704 p. Fig. 3.26, fig. 3.28, fig. 3.29

22. US 2007/0115056, fig. 2

23. US 7548117, fig. 5

24. EP 0 293,486 B1, fig. 5

25. Patt Boonyaporn, Varakorn Kasemsuwan. A High Performance Class AB CMOS Rail to Rail Voltage Follower // ASIC, 2002. Proceedings. 2002 IEEE Asia-Pacific Conference on, pp. 161-163

26. US 4,420,726, fig. 1 - fig. 3

27. The elemental base of radiation-resistant information-measuring systems: monograph / N.N. Prokopenko, O.V. Dvornikov, S.G. Krutchinsky; under the general. ed. Doctor of Technical Sciences prof. N.N. Prokopenko; FSBEI HPE “South-Ros. state University of Economics and Service. ” - Mines: FSBEI HPE "URGUES", 2011. - 208 p.

28. OV Dvornikov, VL Dziatlau, NN Prokopenko, KO Petrosiants, NV Kozhukhov and VA Tchekhovski, "The accounting of the simultaneous exposure of the low temperatures and the penetrating radiation at the circuit simulation of the BiJFET analog interfaces of the sensors," 2017 International Siberian Conference on Control and Communications (SIBCON), Astana, Kazakhstan, 2017, pp. 1-6. DOI: 10.1109 / SIBCON.2017.7998507

Claims (1)

A bipolar-field buffer amplifier containing the first (1) field-effect transistor, the gate of which is connected to the input of the device (2), the second (3) field-effect transistor, the drain of which is connected to the first (4) bus of the power source, the output bipolar transistor (5), the emitter of which is connected to the output of the device (6), the base is connected to the second (7) bus of the power source through the first (8) current-stabilizing two-terminal network, and the collector of the output bipolar transistor (5) is connected to the second (7) bus of the power source, characterized in that source of the first (1) by the transistor is connected to the output of the device (6) and the source of the second (3) field-effect transistor, the drain of the first (1) field-effect transistor is connected to the input of the additional current mirror (9), matched with the first (4) bus of the power source, and the output of the additional current mirror (9) is connected to the base of the output bipolar transistor (5) and connected to the gate of the second (3) field effect transistor.

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