RU2436226C1 - Differential operational amplifier with paraphase output - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: differential operational amplifier with paraphase output comprises an input differential cascade (1) with the first (2) and second (3) current outputs, the first (4) and the second (5) inputs, the first (6) bus of power supply source, connected to the common emitter circuit of the input differential cascade (1), the first (7) output transistor, the base of which is connected to the second (3) current output of the input differential cascade (1), the collector is connected to the bus of the second (8) source of power supply, and the emitter is connected to the first (9) auxiliary output of the device and via the first (10) current-stabilising dipole is connected to the first (6) bus of the power supply source, the second (11) output transistor, the base of which is connected to the first (2) current output of the input differential cascade (1), the collector is connected to the bus of the second (8) source of power supply, and the emitter is connected to the second (12) auxiliary output of the device and via the second (13) current-stabilising dipole is connected to the first (6) bus of the power supply source, the third (14) and the fourth (15) output transistors, emitters of which are connected to the second (8) bus of the supply source, bases are connected to each other, the collector of the third (14) output transistor is connected to the base of the second (11) output transistor, the collector of the fourth (15) output transistor is connected to the base of the first (7) output transistor. The following components were introduced into the circuit: the first (16), the second (17) and the third (18) additional transistors, emitters of which are connected to each other and via the third (19) current-stabilising dipole are connected to the first (6) bus of the power supply source, collectors of the first (16) and second (17) additional transistors are combined and connected to the bases of the third (14) and fourth (15) output transistors, the base of the first (16) additional transistor is connected to the first (4) input of the device, the base of the second (17) additional transistor is connected to the second (5) input of the device, the collector of the third (18) additional transistor is connected to the second (8) bus of the power supply source, besides, the first (9) auxiliary output of the device is connected to the base of the third (18) additional transistor via the first (20) resistor of feedback, and the second (12) auxiliary output of the device is connected to the base of the third (18) additional transistor via the second (21) resistor of feedback.

EFFECT: development of conditions, under which output static cophased voltage of DA will have high stability and zero value.

3 cl, 12 dwg

Description

The invention relates to the field of radio engineering and communication and can be used as a device for amplifying analog signals in the structure of analog microcircuits for various functional purposes (for example, decision amplifiers (op amps), comparators, bridge power amplifiers, etc.).

There are known schemes of classical two-stage differential amplifiers (DU) with a paraphase output, which became the basis of many serial analog microcircuits [1-8].

In addition, the remote controls of this class are actively used in the structure of microwave devices implemented on the basis of the latest SiGe technologies. This is due to the possibility of building on their basis active RC-filters of the gigahertz range for modern and promising communication systems, bridge power amplifiers, etc.

The closest prototype (figure 1) of the claimed device is a differential amplifier, presented in the article Budyakova A.S., Prokopenko N.N., Manzhuly V.G. Analysis of the frequency characteristics of the input circuits of the input stages of the microwave operational amplifiers for the complex functional blocks of radiation-resistant equipment of the new generation // in the journal "Scientific and Technical Journal of St. Petersburg State Polytechnical University. Informatics, Telecommunications. Control". - No. 3 (101) / 2010. - p.210, Fig. 4 and containing the input differential stage 1 with the first 2 and second 3 current outputs, the first 4 and second 5 inputs, the first 6 power supply bus connected to the common emitter circuit of the input differential stage 1, the first 7 output transistor , the base of which is connected to the second 3 current output of the input differential stage 1, the collector is connected to the bus of the second 8 power source, and the emitter is connected to the first 9 auxiliary output of the device and through the first 10 current-stabilizing two-terminal connected to the first 6 bus the power source, the second 11 output transistor, the base of which is connected to the first 2 current output of the input differential stage 1, the collector is connected to the bus of the second 8 power supply, and the emitter is connected to the second 12 auxiliary output of the device and through the second 13 current-stabilizing two-terminal connected to the first 6 bus power supply, the third 14 and fourth 15 output transistors, the emitters of which are connected to the second 8 bus of the power source, the bases are connected to each other, the collector of the third 14 output transistor is connected to the base of the second 11 output transistor, the collector of the fourth 15 output transistor is connected to the base of the first 7 output transistor.

A significant drawback of the known remote control is that it has an unstable output common-mode voltage level, depending on the parameters of the input differential stage 1 and the voltage of the power sources. This greatly complicates its coordination with the subsequent functional units of the SF blocks of systems on the A / d and D / a class crystals.

The main objective of the invention is to create conditions under which the output static common-mode voltage of the remote control will have high stability and zero value.

The problem is solved in that in a differential operational amplifier with a paraphase output of Fig. 1, containing an input differential stage 1 with a first 2 and a second 3 current outputs, a first 4 and a second 5 inputs, a first 6 bus of a power source connected to a common emitter circuit of the input differential stage 1, the first 7 output transistor, the base of which is connected to the second 3 current output of the input differential stage 1, the collector is connected to the bus of the second 8 power supply, and the emitter is connected to the first 9 auxiliary the output of the device and through the first 10 the current-stabilizing two-terminal is connected to the first 6 bus of the power source, the second 11 output transistor, the base of which is connected to the first 2 current output of the input differential stage 1, the collector is connected to the bus of the second 8 power supply, and the emitter is connected to the second 12 auxiliary the output of the device and through the second 13 current-stabilizing two-pole connected to the first 6 bus power source, the third 14 and fourth 15 output transistors, the emitters of which are connected to the second 8 bus source power supply, the bases are connected to each other, the collector of the third 14 output transistor is connected to the base of the second 11 output transistor, the collector of the fourth 15 output transistor is connected to the base of the first 7 output transistor, new elements and communications are provided - the first 16, second 17 and third 18 additional transistors, the emitters of which are connected to each other and through the third 19 current-stabilizing bipolar connected to the first 6 bus power supply, the collectors of the first 16 and second 17 additional transistors inen and connected with the bases of the third 14 and fourth 15 output transistors, the base of the first 16 additional transistor is connected to the first 4 input of the device, the base of the second 17 additional transistor is connected to the second 5 input of the device, the collector of the third 18 additional transistor is connected to the second 8 bus of the power source, moreover, the first 9 auxiliary output of the device is connected to the base of the third 18 additional transistor through the first 20 feedback resistor, and the second 12 auxiliary output of the device is connected to the base t Third 18 of the additional transistor through the second 21 feedback resistor.

In Fig.1 shows a diagram of the remote control prototype.

Figure 2 shows a diagram of the inventive device in accordance with claim 1 of the claims.

Figure 3 shows the scheme of the remote control according to claim 2 and claim 3 of the claims.

In Fig.4 shows a diagram of the claimed remote control of Fig.3 in a computer simulation environment Cadance on SiGe models of integrated transistors.

The graphs of Fig. 5 show the dependence of the constant component of the output common-mode static voltage of the remote control of Fig. 4 on the current of the third 19 current-stabilizing two-terminal network (I ₁₉ = I _var ) with the resistance of the feedback resistors 20 and 21 R ₂₀ = R ₂₁ = 1 kOhm.

Figure 6 presents the time dependence of the output sinusoidal voltages of the remote control of figure 4.

In Fig.7 shows the dependence of the gain on the voltage of the remote control of Fig.4 from frequency.

Fig. 8 shows the dependence of the constant component of the output common-mode static voltage of the remote control of Fig. 4 on the current of the third 19 current-stabilizing two-terminal network (I ₁₉ = I _var ) at the resistance of the feedback resistors 20 and 21 R ₂₀ = R ₂₁ = 10 kOhm.

In Fig.9 shows a diagram of the driver of a differential communication line based on the claimed remote control of Fig.4 in a computer simulation environment Cadance on SiGe models of integrated transistors.

Figure 10 shows the dependence of the gain on the voltage of the driver of figure 9 on the frequency without correction capacity.

Figure 11 shows the time dependence of the output sinusoidal voltage of the driver of Fig.9.

On Fig presents the dependence of the gain on the voltage of the driver of Fig.9 on the frequency with the correction capacitance C _corr = 500 fF between the bases of transistors Q ₁₀ and Q ₁₁ with uneven amplitude-frequency characteristics of less than 1 dB.

The differential operational amplifier with a paraphase output of FIG. 2 contains an input differential stage 1 with a first 2 and a second 3 current outputs, a first 4 and a second 5 inputs, a first 6 power supply bus connected to a common emitter circuit of the input differential stage 1, and a first 7 output transistor , the base of which is connected to the second 3 current output of the input differential stage 1, the collector is connected to the bus of the second 8 power supply, and the emitter is connected to the first 9 auxiliary output of the device and through the first 10 current an abiliating two-terminal device is connected to the first 6 bus of the power source, the second 11 output transistor, the base of which is connected to the first 2 current output of the input differential stage 1, the collector is connected to the bus of the second 8 power supply, and the emitter is connected to the second 12 auxiliary output of the device and through the second 13 a current-stabilizing two-terminal device is connected to the first 6 bus of the power source, the third 14 and fourth 15 output transistors, the emitters of which are connected to the second 8 bus of the power source, the bases are connected to each other, the collector of the third 14 output transistor is connected to the base of the second 11 output transistor, the collector of the fourth 15 output transistor is connected to the base of the first 7 output transistor. The first 16, second 17 and third 18 additional transistors are introduced into the circuit, the emitters of which are connected to each other and through the third 19 are the current-stabilizing two-terminal devices connected to the first 6 bus of the power supply, the collectors of the first 16 and second 17 additional transistors are combined and connected to the bases of the third 14 and fourth 15 output transistors, the base of the first 16 additional transistor is connected to the first 4 input of the device, the base of the second 17 additional transistor is connected to the second 5 input of the device, the collector of the third 18 additional itelnogo transistor associated with the second eight power source bus, the first 9 auxiliary output device connected to the base of the third 18 additional transistor through a first 20, a feedback resistor, and the second 12 auxiliary output device connected to the base of the third 18 additional transistor through a second 21, a feedback resistor. In a particular case, the input differential stage 1 is implemented on transistors 22 and 23 and a current source 24.

As the first 10, second 13, and third 19 current-stabilizing two-terminal devices, the authors recommend using classical sources of reference current on transistors or relatively high-resistance resistors.

In Fig. 3, in accordance with claim 2, the first 9 auxiliary output of the device is connected to the base of the third 18 additional transistor through the first 25 additional buffer amplifier and the first 20 feedback resistor connected in series, and the second 12 auxiliary output of the device is connected to the base of the third 18 additional transistor through series-connected second 26 additional buffer amplifier and second 21 feedback resistor.

As additional buffer amplifiers 25 and 26, the authors recommend the use of various classic emitter repeaters, including those based on so-called “diamond” transistors. In addition, in FIG. 3, in accordance with claim 3 of the claims, an additional pn junction 27 is included between the combined emitters and the combined bases of the third 14 and fourth 15 output transistors.

Consider the operation of the remote control of Fig.3.

The static current mode of the transistors of the proposed remote control is set by the current-stabilizing two-terminal networks 19, 24, 10, and 13. Moreover, the collector and emitter currents of the transistors of the circuit:

where I ₀ is the set value of the reference current, for example, 1 mA.

на Вых.2 ДУ при нулевом входном сигнале (u_вх=0) можно найти из уравнения:Static voltages U ₉ at the output Output. * 1 and U

at Output 2, the remote control with a zero input signal (u _in = 0) can be found from the equation:

where U _eb . ₁₈ = U _eb.l6 = U _eb.l7 - voltage "emitter-base" of transistors 18, 16 and 17 at the same emitter currents I _ei = 0.5I ₀ ;

I _{b. 18} - base current of the third additional transistor 18 in the feedback resistor 20 (21).

Thus, at typical values of the base currents of the transistor 18, as well as at R ₂₀ = R ₂₁ = 500 ÷ 1000 Ohms, the in-phase output voltage of the remote control of Fig. 3 is practically zero in a wide range of temperature and radiation influences, as well as changes in supply voltages. This is very important for the coordination of the claimed remote control with subsequent functional units of electronic equipment.

The graphs of Fig. 6 show that in the remote control circuits of Fig. 4, the range of variation of u _out at low-voltage power supply (± 2 V) lies within ± 1 V. Moreover, the gain in voltage of the remote control is more than 50 dB (Fig. 7).

независимо от статических параметров дополнительных буферных усилителей 25 и 26. Однако в схеме фиг.3, соответствующей П.2 формулы изобретения, в низкоомной нагрузке, включенной между выходами Вых.^* ₁ и Вых.^* ₂, могут быть получены значительно большие мощности, которые определяются свойствами буферных усилителей 25 и 26. Кроме этого в архитектуре рис.3 при повышенных напряжениях питания максимальные амплитуды выходных напряжений положительной U

и отрицательной U

полярностей близки к сумме напряжений первого 6 Е

и второго Е

8 источников питания:In the circuit of FIG. 3, which differs from the circuit of FIG. 2 by the presence of additional buffer amplifiers 25 and 26, the requirements for the resistance values of the feedback resistors 21 and 22 are significantly reduced, which makes it possible to obtain Outputs at the outputs. ^* ₁ and Exit. ^* ₂ zero static voltage levels U

regardless of the static parameters of additional buffer amplifiers 25 and 26. However, in the circuit of figure 3, corresponding to claim 2 of the claims, in the low-impedance load connected between the outputs of the outputs. ^* ₁ and Exit. ^* ₂ , significantly higher powers can be obtained, which are determined by the properties of buffer amplifiers 25 and 26. In addition, in the architecture of Fig. 3, at increased supply voltages, the maximum amplitudes of the output voltages are positive U

and negative U

polarities are close to the sum of the voltages of the first 6 E

and second E

8 power supplies:

The results of computer simulation of Fig. 11, Fig. 12 of the diagram of Fig. 9 show that, based on the proposed remote control, broadband drivers of differential communication lines of the GHz range are implemented.

Thus, the claimed differential operational amplifier has a zero level of output common-mode voltage. This is very important for its coordination with the subsequent functional units of various systems on the chip, as well as for obtaining a wider range of output antiphase voltages.

Information sources

1. Budyakov A.S., Prokopenko N.N., Manzhula V.G. Analysis of the frequency characteristics of subcircuits of input stages of microwave operational amplifiers for complex functional blocks of radiation-resistant equipment of a new generation [Text] / A.S. Budyakov, N.N. Prokopenko, V.G. Manzhula // Scientific and Technical Journal of St. Petersburg State Polytechnical University. Informatics, Telecommunications. Control. - No. 3 (101) / 2010. - P.210, Fig. 4.

2. Microwave operational amplifiers OA-1 - OA-3 based on the SG25H2 process technology and their practical application in communication systems: a training manual / A. Budyakov, K.Schmalz, N. Prokopenko, C.Scheytt, R. Ostrovsky . - Mines: Publishing house of SRUES, 2010. - P.23, Fig. 2.11.

3. Budyakov A.S. Microcircuit of the low-voltage operational amplifier OA-3, 0_T214_bench_www with increased attenuation of the common-mode signal in the high frequency range and its practical application in automation and telecommunication devices [Text] / AS Budyakov, NN Prokopenko, SV Kryukov // Problems of modern analog microcircuitry: VII international scientific and practical seminar. In 2 hours, part 1 / ch. ed. N.N. Prokopenko; Editorial: V.G. Nemudrov [et al.]. - Mines: GOU VPO "YURGUES", 2009. - P.17-22, Fig. 1.

4. Circuit design of microwave operational amplifiers for analog interfaces with deep feedback [Text] / A.S. Budyakov, N.N. Prokopenko, K.Schmalz, C.Scheytt, P.Ostrovskyy // Problems of developing promising micro- and nanoelectronic systems - 2008. Collection of scientific papers of the III All-Russian scientific and technical conference / under the total. ed. Academician of the Russian Academy of Sciences A.L. Stempkovsky. - M .: Institute of Design Problems in Microelectronics RAS, 2008. - P.301-306, Fig. 6, Fig. 7.

5. US patent No. 4.007.427.

6. US patent No. 4.101.842, fig.1.

7. Patent SU 414704.

8. U.S. Patent 5,610,547, fig. 33.

Claims (3)

1. A differential operational amplifier with a paraphase output, comprising an input differential stage (1) with first (2) and second (3) current outputs, first (4) and second (5) inputs, the first (6) power supply bus connected to the common emitter circuit of the input differential stage (1), the first (7) output transistor, the base of which is connected to the second (3) current output of the input differential stage (1), the collector is connected to the bus of the second (8) power source, and the emitter is connected to the first (9) the auxiliary output of the device and through the high (10) current-stabilizing two-terminal is connected to the first (6) bus of the power source, the second (11) output transistor, the base of which is connected to the first (2) current output of the input differential stage (1), the collector is connected to the bus of the second (8) power source and the emitter is connected to the second (12) auxiliary output of the device and through the second (13) current-stabilizing two-terminal device is connected to the first (6) bus of the power source, the third (14) and fourth (15) output transistors, the emitters of which are connected to the second (8) bus power supply base connected to each other, the collector of the third (14) output transistor is connected to the base of the second (11) output transistor, the collector of the fourth (15) output transistor is connected to the base of the first (7) output transistor, characterized in that the first (16) is introduced into the circuit , the second (17) and third (18) additional transistors, the emitters of which are connected to each other and connected through the third (19) current-stabilizing two-terminal to the first (6) bus of the power supply, the collectors of the first (16) and second (17) additional transistors are combined and related to bases the third (14) and fourth (15) output transistors, the base of the first (16) additional transistor is connected to the first (4) input of the device, the base of the second (17) additional transistor is connected to the second (5) input of the device, the collector of the third (18) additional transistor is connected to the second (8) bus of the power source, and the first (9) auxiliary output of the device is connected to the base of the third (18) additional transistor through the first (20) feedback resistor, and the second (12) auxiliary output of the device is connected to the base of the third ( 18) an additional transistor through a second (21) feedback resistor. 2. The differential operational amplifier with a paraphase output according to claim 1, characterized in that the first (9) auxiliary output of the device is connected to the base of the third (18) additional transistor through the first (25) additional buffer amplifier and the first (20) feedback resistor communication, and the second (12) auxiliary output of the device is connected to the base of the third (18) additional transistor through the second (26) additional buffer amplifier and the second (21) feedback resistor connected in series. 3. The differential operational amplifier with a paraphase output according to claim 1, characterized in that between the combined emitters and the combined bases of the third (14) and fourth (15) output transistors, an additional pn junction (27) is included.

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