RU2568780C1 - Cascade amplifier with expanded range of working frequencies - Google Patents

Abstract

FIELD: radio engineering, communication.

SUBSTANCE: cascade amplifier contains the first and the second input transistors, the first output transistor the emitter of which is connected to the collector of the first input transistor, and the base is connected with the shift voltage source, the second output transistor the emitter of which is connected to the collector of the second input transistor, and the base is connected with the shift voltage source. The base of the first output transistor is connected with the shift voltage source through the first additional resistor, the base of the second output transistor is connected with the shift voltage source through the second additional resistor, the base of the first output transistor is connected to base of the first additional transistor the collector of which is connected to the emitter of the second output transistor, the base of the second output transistor is connected to base of the second additional transistor the collector of which is connected to the emitter of the first output transistor, and emitters of the first and the second additional transistors are connected with the second power supply bus through the additional current-stabilizing two-pole network.

EFFECT: increase of value of the top boundary frequency without deterioration of coefficient of voltage amplification in the range of medium frequencies.

5 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, broadband and selective amplifiers of the high and microwave ranges, implemented by new and promising technologies).

In modern microelectronics, classical cascode amplifiers (KUs) with a resistive (or resistive-inductive) load included in the collector (drain) circuit of the output transistor are widely used [1-32].

The closest in technical essence to the claimed device is KU, presented in patent US 6.825.723 fig. 6. It contains (Fig. 1) the first 1 and second 2 input transistors, the emitters of which are combined and connected to the first bus 3 of the power source through a current-stabilizing two-terminal 4, and the bases are connected to the corresponding first 5 and second 6 inputs of the device, the first 7 output transistor , the collector of which is connected to the second 8 bus of the power source through the first 9 bipolar load and connected to the first 10 output of the device, the emitter is connected to the collector of the first 1 input transistor, and the base is connected to a bias voltage source of 11, the second 12 a transistor having its collector connected to the second power supply bus 8 via a second two-terminal load 13 and connected to the second output of the apparatus 14, the emitter connected to the collector of the second input transistor 2 and the base connected to a bias voltage source 11.

A significant drawback of the known KU, figure 1, the architecture of which is also present in other KU [1-32], is that it has not high enough upper cutoff frequency (f _in level - 3 dB). This is due to the negative effect on f _{in the} parasitic capacitance on the substrate (C _p ) and the stray collector - base _Cb base of its output transistors (7, 8). The numerical values of C _p and C _kb for a number of technological processes having, for example, increased radiation resistance, are one of the main factors that determine the frequency range of broadband amplifiers based on KU, FIG. one.

The main objective of the invention is to expand the range of operating frequencies KU (increase it f _in ) without deterioration of the voltage gain in the medium frequency range.

An additional task is to increase the gain in the mid-frequency range.

The tasks are solved in that in the cascode amplifier, FIG. 1, containing the first 1 and second 2 input transistors, the emitters of which are combined and connected to the first bus 3 of the power source through a current-stabilizing two-terminal 4, and the bases are connected to the corresponding first 5 and second 6 inputs of the device, the first 7 output transistor, the collector of which is connected to the second 8 bus power source through the first 9 two-pole load and connected to the first 10 output of the device, the emitter is connected to the collector of the first 1 input transistor, and the base is connected to a bias voltage source 11, the second 12 output a transistor, the collector of which is connected to the second 8 bus of the power source through the second 13 bipolar load and connected to the second 14 output of the device, the emitter is connected to the collector of the second 2 input transistor, and the base is connected to a bias voltage source 11, new elements and communications are provided - the base of the first 7 of the output transistor is connected to a bias voltage source 11 through the first 15 additional resistor, the base of the second 12 output transistor is connected to a bias voltage source 11 through the second 16 additional resistor Oh, the base of the first 7 output transistor is connected to the base of the first 17 additional transistor, the collector of which is connected to the emitter of the second 12 output transistor, the base of the second 12 output transistor is connected to the base of the second 18 additional transistor, the collector of which is connected to the emitter of the first 7 output transistor, and emitters the first 17 and second 18 additional transistors are connected to the second 8 bus power supply through an additional current-stabilizing two-terminal 19.

A prototype amplifier circuit is shown in FIG. one.

In FIG. 2 presents a diagram of the inventive device in accordance with the claims.

In FIG. 3 is a diagram of the inventive device of FIG. 2 in the environment of PSpice on the models of integrated transistors of OJSC NLP Pulsar.

In FIG. 4 shows the amplitude-frequency characteristic of the gain of the voltage KU, FIG. 3, with different values of the resistances of the first 15 and second 16 additional resistors (in the notation of Fig. 2). From these graphs it follows that the range of operating frequencies of the inventive cascode amplifier extends more than 2 times.

In FIG. 5 shows the amplitude-frequency characteristic of the voltage gain KU of FIG. 3 at higher resistance values of the first 15 and second 16 additional resistors. From these graphs it follows that in this mode, the voltage gain of the claimed remote control can reach 60-100 dB. However, with higher values of the resistances of the first 15 and second 16 additional resistors, the upper boundary frequency of the KU decreases (f _in level - 3 dB).

A cascode amplifier with an extended operating frequency range, FIG. 2, contains the first 1 and second 2 input transistors, the emitters of which are combined and connected to the first bus 3 of the power supply through a current-stabilizing two-terminal 4, and the bases are connected to the corresponding first 5 and second 6 inputs of the device, the first 7 output transistor, the collector of which is connected to the second 8 bus power source through the first 9 two-pole load and connected to the first 10 output of the device, the emitter is connected to the collector of the first 1 input transistor, and the base is connected to a bias voltage source 11, the second 12 output tr nzistor, the collector of which is connected to the second 8 bus of the power source through the second 13 bipolar load and connected to the second 14 output of the device, the emitter is connected to the collector of the second 2 input transistor, and the base is connected to a bias voltage source 11. The base of the first 7 output transistor is connected to the source bias voltage 11 through the first 15 additional resistor, the base of the second 12 output transistor is connected to a bias voltage source 11 through the second 16 additional resistor, the base of the first 7 output transistor connected to the base of the first 17 additional transistor, the collector of which is connected to the emitter of the second 12 output transistor, the base of the second 12 output transistor is connected to the base of the second 18 additional transistor, the collector of which is connected to the emitter of the first 7 output transistor, the emitters of the first 17 and second 18 additional transistors connected to the second 8 bus power source through an additional current-stabilizing two-terminal 19. In FIG. 2 capacitors 21 and 22 simulate the effect on the operation of the circuit of stray capacitances on the substrate of transistors 7 and 12, as well as load capacities. Spurious capacitors 23 and 24 take into account the influence on the operation of the circuit of the stray capacitance of the collector - the base of the corresponding first 7 and second 12 output transistors. Consider the operation of the KU, FIG. 2.

In the high-frequency region, on the amplitude-frequency characteristic of the KU, FIG. 2, for the first 10 output, parasitic capacitances 21 and 23 begin to influence the collector circuit of the first 7 output transistor. Moreover, for the circuit, FIG. 2, the following equations are valid:

- комплекс тока через паразитный конденсатор 23;Where $${\dot{I}}_{\mathrm{from}\mathrm{to}7}$$

- complex current through the stray capacitor 23;

- комплекс напряжения на выходе устройства 10;

- voltage complex at the output of the device 10;

- комплексное сопротивление паразитного конденсатора 21 на частоте сигнала ω;

- the complex resistance of the stray capacitor 21 at a signal frequency ω;

- комплексное сопротивление паразитного конденсатора 23 на частоте сигнала ω.

- the complex resistance of the stray capacitor 23 at the frequency of the signal ω.

создает на первом 15 дополнительном резисторе напряжение:Current complex $${\dot{I}}_{\mathrm{from}\mathrm{to}7}$$

creates a voltage on the first 15 additional resistor:

, где g_m17-18 - проводимость передачи каскада на транзисторах 17, 18, g_ml7-18 ≈ (r_э18+r_э17)^-1, r_э17, r_э2 - сопротивления эмиттерных переходов транзисторов 17 и 18.which is converted to current

where g _m17-18 is the transmission conductivity of the cascade on transistors 17, 18, g _ml7-18 ≈ (r _e18 + r _e17 ) ^-1 , r _e17 , r _e2 are the resistance of the emitter junctions of transistors 17 and 18.

If the parameters of the capacitors of the capacitors 21, 23 satisfy the equation:

, $${\dot{I}}_{ск7}$$

и

(в уравнении 3: Ι₀ - параметр дополнительного токостабилизирующего двухполюсника 19, φ_т=26 мВ - температурный потенциал; α₇≈1 - коэффициент усиления по току эмиттера транзистора 7).then in the output circuit of the device 10 provides mutual compensation of currents $${\dot{I}}_{21}$$

, $${\dot{I}}_{\mathrm{from}\mathrm{to}7}$$

and

(in equation 3: Ι ₀ is the parameter of the additional current-stabilizing two-terminal device 19, φ _t = 26 mV is the temperature potential; α ₇ ≈1 is the current gain of the emitter of transistor 7).

Ultimately, when condition (3) is satisfied, the operating frequency range of the control unit, FIG. 2, expanding. This conclusion is confirmed by the results of computer simulation of FIG. four.

Thus, the claimed circuit design of the cascode amplifier is characterized by a higher range of operating frequencies.

INFORMATION SOURCES

1. US Patent No. 3,660.773

2. French Patent No. 1,484.340

3. Germany patent No. 1.214.733

4. Patent of England No. 1,520.085

5. US Patent No. 3,482.177

6. Patent of England No. 1,212.342 Н3Т

7. German patent No. 1,537.590

8. French Patent No. 1,548.008

9. The patent of Germany No. 2.418.455

10. US Patent No. 5.185.582 fig. one

11. US Patent No. 4,151.483 fig. 2, fig. 3

12. Japan Patent JP 61264806

13. US Patent No. 3,660.773

14. A. ST. USSR No. 427451

15. US patent No. 6.825.723 fig. 3

16. US Patent No. 4,151.484

17. US Patent No. 3,882,410 fig. 3

18. Patent application WO 2004/030207

19. US patent No. 4.021.749 fig. 2

20. US Patent No. 3,693.108 fig. 9

21. US patent No. 7.113.043 fig. 2

22. US Patent Application 2006/0033562

23. US Patent Application 2006/0132242

24. US Patent Application 2006/0119435

25. US Patent Application 2005/0248408

26. US patent No. 6.204.728

27. US Patent No. 6,278.329

28. US patent application 2005/0225397

29. US Patent No. 5,451.906

30. US patent No. 7,098.743 fig. one

31. British Patent GB No. 1431481 fig

32. US Patent No. 6,515,547 fig. 2

Claims (1)

A cascode amplifier with an extended operating frequency range, containing the first (1) and second (2) input transistors, the emitters of which are combined and connected to the first bus (3) of the power supply through a current-stabilizing two-terminal device (4), and the bases are connected to the corresponding first (5) and the second (6) inputs of the device, the first (7) output transistor, the collector of which is connected to the second (8) bus of the power supply through the first (9) two-terminal load and connected to the first (10) output of the device, the emitter is connected to the collector of the first (1 ) input transistor pa, and the base is connected to a bias voltage source (11), the second (12) output transistor, the collector of which is connected to the second (8) bus of the power source through the second (13) load two-pole terminal and connected to the second (14) output of the device, the emitter is connected to the collector of the second (2) input transistor, and the base is connected to a bias voltage source (11), characterized in that the base of the first (7) output transistor is connected to a bias voltage source (11) through the first (15) additional resistor, the base of the second ( 12) the output transistor is connected to bias voltage source (11) through the second (16) additional resistor, the base of the first (7) output transistor is connected to the base of the first (17) additional transistor, the collector of which is connected to the emitter of the second (12) output transistor, the base of the second (12) output transistor connected to the base of the second (18) additional transistor, the collector of which is connected to the emitter of the first (7) output transistor, and the emitters of the first (17) and second (18) additional transistors are connected to the second (8) bus of the power supply through an additional Tel'nykh tokostabiliziruyuschy bipole (19).

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