JPH0685551A - Wide band amplifier circuit - Google Patents

Abstract

PURPOSE:To provide the wide band amplifier circuit which can output a large amplitude wide band signal without increasing power consumption. CONSTITUTION:Since the charge/discharge of a capacitor 21 for peaking can be accelerated by driving the capacitor 21 for peaking in the amplifier circuit with a push/pull circuit composed of transistors 4 and 22, the power consumption can be reduced by decreasing a bias current. When a feedback impedance 7 is connected to the emitter of a transistor 9, the output signal can be fed back to the input part of the amplifier circuit as a current signal over the frequency range of a wide band, thereby the large output wide band amplifier circuit can be constituted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wide-band amplifier circuit, and more particularly to a large-output low-power consumption amplifier circuit suitable for use in a picture tube drive circuit that needs to output a large-amplitude wide-band signal.

[0002]

2. Description of the Related Art In recent years, the frequency band of a picture tube drive circuit has become wider than ever with the increase in resolution of display devices. Especially for computer displays for CAD / CAM, etc., from 50 MHz to 300 MHz
A band of about MHz is needed. Further, the voltage amplitude of the drive signal is required to be about 30 V for a monochrome picture tube and about 50 V for a color picture tube, and the amplitude is further increased with the recent enlargement of the display screen.

As a result, there is a problem that the power consumption of the drive circuit is increased and the circuit components are increased in size and weight. In consideration of this problem, FIG. 2 shows a conventional capacitive load drive circuit such as a picture tube or a cathode ray tube disclosed in Japanese Patent Publication No. 57-20724.

In the conventional capacitive load driving circuit shown in FIG. 2, a wide band signal applied from the signal source 1 to the input terminal 2 is divided into a low frequency component and a high frequency component to be amplified and a capacitive load 6 is obtained. It is configured to be driven. The low-frequency component is a transistor 2 having a feedback path composed of an input resistor 27, a feedback resistor 7 and a frequency characteristic compensating capacitor 28.
The parallel feedback amplification circuit composed of 5 amplifies while suppressing temperature drift and distortion.

Here, by suppressing the collector current of the transistor 4 forming the constant current circuit for bias,
The power consumption of the amplifier circuit can also be suppressed. The high frequency component is amplified by the series feedback amplifier circuit including the transistor 26 to which the feedback resistor 31 and the peaking capacitor 32 are connected. At that time, both of the above frequency components are combined at the emitter of the base-grounded transistor 3 and sent to the output terminal 5.

[0006]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
There is a problem that a wideband signal cannot be amplified to a sufficiently large signal amplitude. That is, when a high frequency signal is amplified to a large amplitude by using the capacitive load driving circuit shown in FIG. 2, the capacitor 32 is suppressed while suppressing the power consumption of the circuit.
It is often the case that a sufficient output amplitude cannot be obtained because the transistor 26 is cut off due to the side effect of performing peaking using the. A more detailed description is added below.

When the input signal falls, it is necessary to discharge the peaking capacitor 32 so that the voltage waveform of the emitter of the transistor 26 follows the input signal. However, the maximum value of the discharge current of the peaking capacitor 32 is suppressed to the value of the bias current of the transistor 26. Therefore, in the state where the bias current of the transistor 26 is suppressed in order to suppress the power consumption of the circuit,
When the input signal has a large amplitude and falls during an extremely short transition time, the peaking capacitor 32 cannot be fully discharged and the transistor 26 is cut off.

The prior art also has a problem that the characteristics of the amplifier circuit deteriorate due to the influence of the frequency characteristics of the feedback system. For example, the stability of the amplifier circuit may be impaired due to the influence of the phase delay generated in the feedback network, and the frequency band may not be sufficiently secured. Further, if the frequency band of the feedback circuit network cannot be sufficiently secured, an excessive shoot may occur in the transient response of the amplifier circuit, or the frequency band of the amplifier circuit may not be sufficiently secured as in the above case.

Further, due to the load effect of the feedback network,
The large-amplitude wide-band output capability of the amplifier circuit may be impaired. Also in FIG. 2, due to the feedback circuit elements of the input resistor 27, the feedback resistor 7, the frequency characteristic compensating capacitor 28, and the parasitic capacitance and parasitic inductance of the transistor 25,
The characteristic deterioration as described above occurs in the amplifier circuit. Further, although the frequency characteristic compensating capacitor 28 is used to improve the transient response characteristic of the amplifier circuit, there is a problem that the frequency band at the time of large amplitude output is narrowed due to the load effect on the amplifier circuit.

An object of the present invention is to provide a wide band amplifier circuit capable of outputting a large amplitude wide band signal without increasing power consumption.

[0011]

In order to achieve the above object, in a wide band amplifier circuit of the present invention, as a first means, a peaking capacitor is used as a normal output side (in the present invention, output side of a push-pull circuit). I'm not using it as, but I'm supposed to use it for gain setting).

As a second means for achieving the above object, a feedback network is constructed by connecting the feedback impedance of the output signal to the low impedance terminal of the active element. Further, as a third means, a feedback impedance is connected to the output signal detecting section exhibiting high impedance. Subsequently, as a fourth means, a current signal distribution circuit is connected to the drive element forming the push-pull circuit. Then, as a fifth means, a part of the other signal path is connected to the AC ground terminal of the active element connected to the signal path. Finally, as a sixth means, the peaking element and the output resistor are connected via a capacitor.

[0013]

In the first means for realizing the wide band amplifier circuit of the present invention, the peaking capacitor has the function of improving the frequency characteristic of the amplifier circuit. The push-pull circuit promotes charging and discharging of the peaking capacitor. With the above operation, the above object of the present invention is achieved.

In the above-mentioned second means, the feedback impedance has a function of feeding back the output signal as a current signal. The active element having the low impedance terminal to which the impedance is connected has a function of returning the output signal to the input portion of the amplifier circuit over a wide frequency range. By constructing a feedback network with the above feedback impedance and active elements, the above object of the present invention is achieved.

In the above-mentioned third means, the output signal detection section exhibiting high impedance has a function of guiding the output signal to the detection terminal. The feedback impedance reduces the impedance of the above output signal detection unit and suppresses the time constant,
The output signal is fed back to the input section of the amplifier circuit.
With the above operation, the above object of the present invention is achieved.

In the fourth means, the driving element forming the push-pull circuit has a function of outputting a large-amplitude wide-band signal without increasing power consumption by operating complementarily. The current signal distribution circuit drives the drive element by distributing the current signal over a wide frequency range from the DC component to the high frequency component. With the above operation, the above object of the present invention is achieved.

In the fifth means, the active element connected to the signal path amplifies the signal. The other signal path has a function of canceling the parasitic impedance of the active element connected to the signal path by connecting a part thereof to the AC ground terminal. With the above operation, the above object of the present invention is achieved.

In the above-mentioned sixth means, the peaking element has a function of improving the frequency characteristic of the amplifier circuit.
The output resistance has a function of determining the gain of the amplifier circuit and a function of the peaking element as a damping element. Further, the capacitor connected between the peaking element and the output resistor connects the two at the frequency at which the damping is required. With the above operation, the above object of the present invention is achieved.

With the above operation, it is possible to provide a wide band amplifier circuit capable of outputting a large amplitude wide band signal without increasing power consumption.

[0020]

1 is a circuit diagram showing a basic embodiment of a wide band amplifier circuit according to the present invention. In FIG. 1, the process of signal amplification can be considered as follows.

That is, the voltage signal of the signal source 1 is converted into a current signal via the input impedance 8 and then flows into the input terminal 2 of the amplifier circuit. Since it is considered that the current gain of the amplifier circuit including the elements after the transistor 9 is extremely large, the above-mentioned input current signal is converted again into the amplified voltage signal via the feedback impedance 7, and the output terminal 5
To the capacitive load 6 via.

At this time, the output voltage signal is converted into a feedback current signal via the feedback impedance 7, subtracted from the input current signal by the transistor 9 having a grounded base, and converted into an error voltage signal via the impedance 11. To be done. This error voltage signal is inverted and amplified by the transistor 12 having a grounded-emitter configuration and applied to the transistors 15 and 16 which form a single-ended push-pull circuit (hereinafter referred to as SEPP).

After that, the above-mentioned error voltage signal is complemented by a push-pull operation transistor 3 having a base-grounded structure.
The voltage is amplified via 4 and 4 and becomes an output signal. that time,
Impedances 8 and 7 and 11 and 13 and 14 constituting the circuit, and an input impedance of the grounded base circuit 18
It goes without saying that each of the series synthetic impedances of 20 and 21 can use various synthetic impedances composed of passive elements.

For example, the feedback impedance 7 may be composed of a series combined impedance of a resistor and a coil in order to perform peaking in the high frequency region of the amplifier circuit. Further, in order to improve the delay of the transient response of the amplifier circuit due to the influence of the thermal time constant of the transistor, the feedback impedance 7 can be configured by a circuit network including a parallel combined impedance of a resistor and a capacitor.

Next, of the respective means for realizing the present invention described above, the means applied to the embodiment shown in FIG. 1 will be described. The capacitor 21 forming the input impedance of the above-described grounded base circuit can also be regarded as a peaking capacitor. In the prior art, the capacitor 2
The interruption of the transistor 4 connected to 1 prevents the output signal from having a large amplitude and wide band.

However, in the present embodiment, the grounded base circuit is formed into a push-pull configuration by using the transistor 22 to promote the charging / discharging of the peaking capacitor 21 despite the interruption of the transistor 4. As a bias condition of the transistors 4 and 22 that can be set by the voltage source 23, class AB operation in which the transistor 4 is not interrupted when a low frequency signal is input is preferable in terms of circuit operation.

However, the anode of the power supply 24 and the transistor 4
If the bias current path of the feedback impedance 7 that flows toward the emitter of the transistor 9 is provided by connecting the collector of the resistor via a resistor or the like, class B or C
Any setting such as class operation is possible. Further, the transistors 15 and 16 forming the SEPP also have the action of promoting the charging and discharging of the peaking capacitor 21, and the bias conditions are similar to those of the transistors 4 and 22.

Next, one terminal of the feedback impedance 7 is connected to the emitter of the transistor 9 which is a low impedance terminal in which the signal voltage amplitude is suppressed, and the feedback signal is transmitted as a current signal as described above. Since the signal voltage amplitude is suppressed at the low impedance terminal as described above, the bypass of the signal current to the parasitic capacitance of this terminal and each element connected to the terminal is suppressed.

Therefore, by transmitting the feedback signal as the current signal, the deterioration of the frequency characteristic of the feedback circuit network due to the influence of the parasitic capacitance can be suppressed, and the wide output band of the amplifier circuit can be achieved. Further, since the time constant is reduced in the low impedance terminal, the feedback impedance 7 can be set to a sufficiently high value, and the load effect on the amplifier circuit can be suppressed.

The other terminal of the feedback impedance 7 is connected to an output signal detection section (output terminal 5) showing a high impedance which is a connection point of the collectors of the transistors 3 and 4. By connecting the feedback impedances 7 in parallel, the impedance of the output signal detecting section is reduced. As a result, it is possible to suppress the time constant of the output signal detection unit, expand the frequency band of the open loop gain of the amplifier circuit, and improve the flatness of the frequency characteristic of the closed loop gain.

The basic embodiment of the broadband amplifier circuit of the present invention has been described above with reference to FIG. Hereinafter, various embodiments using each means for realizing the above-described present invention will be described in detail. In that case, the same components as those shown in FIG. 1 are designated by the same reference numerals.

First, FIG. 3 shows an embodiment using the above-mentioned first means and having the least number of constituent elements. In FIG. 3, it is considered that the DC gain is determined by the ratio of the emitter resistance 31 and the output impedance 33, and the high frequency gain is set by the ratio of the capacitance value of the peaking capacitor 32 and the capacitance value of the capacitive load 6. However, when the amplitude or frequency of the input signal applied from the signal source 1 to the input terminal 2 increases, as described above, the transistor 1
The interruption of 6 hinders the charging and discharging of the peaking capacitor 32.

In particular, when the bias current of the transistor 16 is suppressed in order to reduce the power consumption of the amplifier circuit, the tendency of the transistor 16 to be cut off is further promoted. In this embodiment described above, the transistor 15 is added to accelerate the charging / discharging of the peaking capacitor 32, and the strong application of the emitter peaking is made possible so that the amplifier circuit has a wide output wide band.

In FIG. 3, the transistor 16 is set to the class AB bias in which the bias current flows when there is no signal, and the transistor 15 is set to the class C bias in which the current does not flow unless the signal amplitude or the like becomes larger than a certain level. However, an arbitrary bias voltage or bias current setting circuit can be provided between the bases of the transistors 15 and 16 as long as the charging and discharging of the peaking capacitor 32 can be accelerated. It is needless to say that the peaking capacitor 32 may be any circuit network in which a series resistor is inserted to suppress the peaking effect more than necessary and stabilize the peaking effect.

Further, in order to further increase the wide band of the output, a grounded base circuit is provided in the collector of the transistor 16 to form a cascode structure, or SE is provided in front of the output terminal 5.
It goes without saying that a PP or emitter follower circuit can be provided.

It will be apparent that the transistor in FIG. 3 can be replaced by a field effect transistor FET (MOS type or junction type). Please refer to FIG. 47 for a corresponding circuit diagram of the transistors of each polarity and the field effect transistor FET.

Next, FIG. 4 shows an embodiment in which the symmetry of the transient response of the amplifier circuit is improved by using the above-mentioned first means.
In FIG. 4, a push-pull amplifier circuit is realized by driving a SEPP, which is composed of transistors 35 and 36 having a peaking capacitor 37 as a load, through a coupling capacitor 34.

Therefore, a signal current can be output from the collector of the transistor 35 to the output terminal 5, and the rise time as well as the fall time of the output voltage can be shortened. In addition, the emitter resistance 39 to 4 of each transistor
2 has a function of suppressing the instability of SEPP caused by the capacitive load of the peaking capacitors 32 and 37, and a function of setting the bias current of each transistor using the voltages of the bias voltage circuits 23 and 38.

Therefore, the emitter resistors 39 to 42 can be short-circuited and removed, or can be inserted in series on the base side of each transistor. Similarly, the bias voltage circuit 23
And 38 can be short-circuited and removed, transistor 3
It is also possible to set the bias by connecting the emitter of No. 5 to the anode of the power supply 24 via a resistor or the like. Further, if the bias current of the transistor 35 is secured and the output voltage is stabilized by providing the negative feedback path as shown in FIG.
The resistance can be eliminated to reduce the circuit scale and load capacity.

Needless to say, as in the case of the embodiment shown in FIG. 3, a cascode configuration can be used, and a SEPP or emitter follower circuit can be provided before the output terminal 5. The same effect can be obtained by connecting one terminal of the coupling capacitor 34 connected to the base of the transistor 16 to the emitter of the transistor 16.

Next, basic embodiments of the present invention in which the number of circuit elements is reduced to realize the above-mentioned first means are shown in FIGS. 5, 6 and 7, respectively. A circuit diagram of FIG. 8 shows these basic embodiments as a practical amplifier circuit.

In FIG. 8, the transistor 4 having the base-grounded structure is provided without directly discarding the signal current flowing in the collector of the transistor 15 forming the SEPP to the ground point.
By passing the signal to the output terminal 5 via the, the amplifier circuit is designed as a push-pull output. With this configuration, the symmetry of the transient response of the amplifier circuit can be improved without connecting a new transistor to the transistor 4 to configure SEPP.

In the circuit of FIG. 8, the input signal is
Since it is only necessary to drive a single SEPP, it is possible to reduce the characteristic deterioration of the input signal due to the internal impedance of the signal source 1. Here, the bypass capacitor 50
Is used to reduce the driving impedance of the transistor 16, and the bias resistor 47 and the diodes 48 and 49 are used to set the bias of the transistors 15 and 16.

Therefore, it goes without saying that the circuit network consisting of the above-mentioned diodes 48 and 49 may use a larger number of diodes, or may be short-circuited at both ends to be eliminated. Further, the transistor 3 has a grounded base structure like the transistor 4, and forms a cascode circuit together with the transistor 16. The bias resistors 51 and 53 and 29 and the temperature compensating diode 52 set the bias current of the transistor 4, and the capacitor 54 reduces the ground impedance.

Further, the impedance 46 and the constant voltage circuit 45 used for flowing the signal current flowing through the collector of the transistor 15 into the emitter of the transistor 4.
Can be replaced with various elements and circuits shown in FIG. 9, respectively.

As the constant voltage circuit 45, a constant voltage circuit including a Zener diode 55 shown in FIG. 9A and a transistor 56 shown in FIG. 9B can be used as an alternative circuit. Further, the constant voltage circuit 45 can be replaced with only the bypass capacitor 60 shown in FIG. 7B or only a single element such as a resistor or a battery. Similarly, the impedance 46 can be a constant current circuit 61 shown in FIG. 9C or a series combined impedance of the coil 63 and the impedance 62 shown in FIG. 9D. By using the impedance network as shown in FIG. 9D, the peaking effect at an appropriate frequency can be improved.

Subsequently, a basic embodiment (skeleton) in the case where the present invention is applied to a picture tube drive circuit by using the above-mentioned first means
Is shown in FIG. 10, and its practical circuit is shown in FIG. In FIG. 11, the output signal amplified by using the voltage buffer 68, the grounded base circuit, and SEPP is applied to the picture tube 78 via the cathode current detection circuit.

In the amplifying process, generally, the voltage buffer 68 and the grounded base circuit, which can easily obtain the good frequency characteristic by effectively utilizing the performance of the active element, are used. Therefore, the cost of the amplifying circuit can be easily reduced. Become. The circuit operation of this embodiment will be described in detail below. The input signal voltage is passed through a voltage buffer 68 including a low output impedance circuit such as an emitter follower circuit or SEPP, and a series combined impedance of an impedance 72 and a peaking capacitor 71 and an impedance 69 and a peaking capacitor 7 are connected.
Added to 0 parallel combined impedance.

Since the other terminals of these combined impedances are connected to the emitters of the transistors 4 and 3 having the grounded base respectively, the signal voltage is converted into a current and connected to the peaking coil 74 in series. It flows into the output impedance 33 and is output as a voltage signal amplified in a wide band. At the time of amplification, even if the bias current is reduced to reduce the power and the transistors 3 and 4 are frequently cut off, the effect of the push-pull operation of the added transistors 73 and 22 causes
The charging and discharging of the peaking capacitors 70 and 71 are accelerated.

The bias conditions for the transistors 22, 4, 3 and 73 are as follows:
And temperature compensating diodes 48 and 49, 84 and 85. Also, capacitors 50 and 83, 86 and 5
Reference numerals 4 are bypass capacitors for reducing impedance at AC grounding points. Similarly, the bias impedance 91, the emitter impedances 95 and 96, and the temperature compensating diodes 90 and 92 allow the transistor 7 to operate.
Bias conditions of 5 and 76 are set.

When used in a picture tube drive circuit, the above-mentioned emitter impedances 95 and 96 also function as protective elements when the picture tube 78 is discharged in the tube. Transistor 77
The above-described cathode current detection circuit consisting of detects the terminal current of the cathode 79 corresponding to the luminance in order to control the emission luminance of the picture tube 78. The transistor 77, as an emitter follower circuit, transmits the above output signal to the picture tube 78, and at the same time, converts the cathode current flowing into the emitter into a voltage through the detection resistor 99 connected to the collector and outputs the voltage to the detection output terminal 100.

The capacitor 97 is a bypass capacitor that compensates for the asymmetry of the transient response of the emitter follower circuit including the transistor 77. The diode 98 is a protection element that guarantees the reverse breakdown voltage of the transistor 77. Further, the impedance 101 is inserted in series between the parasitic capacitance of the transistor 77 and the ground to prevent the load capacitance of the amplifier circuit from increasing. The coil 102 and the damping resistor 103 are elements for series peaking, and the impedance 104 is a protection circuit of the amplification circuit against the above-mentioned in-tube discharge.

Further, FIG. 12 shows the skeleton of another embodiment in which the present invention is applied to a picture tube drive circuit using the above-mentioned first means, and FIG. 13 shows a practical circuit example thereof. In FIG. 13, as clearly shown in FIG. 12, by using the current mirror circuits CM1 and CM2, both the charging and discharging currents flowing in the peaking capacitors are supplied to the load side, and the amplifier circuit The symmetry of the transient response is improved.

In FIG. 13, an input signal from the signal source 1 is a transistor 109 which constitutes an emitter follower circuit.
Transistor 15 that constitutes SEPP through 110 and 110
And 16 are added. In this case, the transistors 109 and 110, which have different polarities, are replaced by the transistors 15 and 16
And the transistors 15 and 16
"Diamond circuit" is a synthetic circuit composed of SEPP
Is often used.

Of the charging / discharging current flowing through the peaking capacitor 32, the current component flowing through the transistor 15 is the current mirror circuit composed of the transistors 113, 114 and 115 and the current mirror on the anode side of the power supply 24 composed of the transistors 120, 121 and 122. S through the circuit
It is supplied to the bases of the transistors 75 and 76 forming the EPP.

Of the above charging / discharging current, the transistor 16
The current component flowing in the transistor is supplied to the bases of the transistors 75 and 76 complementarily to the collector current of the transistor 122. The voltage of the output terminal 5 is stabilized by controlling the base voltage of the transistor 75 by negative feedback via the feedback impedance 7 and the input impedance 27.

By using the current mirror circuit as described above, the transient response characteristic of the output can be improved in a wide frequency band in which the collector current of the transistor 15 flows. At that time, the increase in power consumption due to the charging / discharging current flowing through the transistor 121 also causes the ratios of the impedances 116 and 118, 123 and 125, which determine the input / output current ratios of the current mirror circuits, to be set appropriately. It can be suppressed by doing.

Further, in order to reduce the power consumption of the transistor 120, a resistor 126 is connected to its collector. Further, a bypass capacitor 127 is added in parallel with the resistor 126 so that the base side of the transistor 120 is not adversely affected by the Miller effect. The base-grounded transistors 3, 4 and 119 each form a cascode circuit between them and the preceding stage, and serve to suppress the Miller effect.

Then, the cathode current can be detected from the terminal 100 via the resistor 99 from the collector current of the transistor 76 biased to the AB class by the diode 90. The capacitor 128 is a bypass capacitor similar to 127 described above. Further, the resistor 105 and the capacitor 106 are connected in parallel with the input impedance 27.
The frequency band of the amplifier circuit can be expanded by adding the serial combination circuit of. In FIG. 8, the base resistors 93 and 94, 107 and 108, 111 and 11 of the respective transistors are shown.
Reference numeral 2 is a stabilizing resistor that suppresses parasitic oscillation.

The embodiment of the present invention in which the push-pull circuit is used to promote charging / discharging of the peaking capacitor to achieve a wider band has been described above. However, when the above-mentioned respective capacitors for peaking are applied to a high frequency signal up to 100 MHz or the capacitance value is increased to be applied to a high gain capacitive load drive circuit, series resonance of the element itself is a problem. Becomes This is because the signal waveform is distorted due to the sudden change in the frequency characteristics around the resonance frequency.

FIG. 14 shows an example of a capacitor suitable as a peaking capacitor used in the present invention. 14
(A) is used, the parallel combined capacitance between the terminals 129 and 130 obtained by connecting in parallel a plurality of small-capacity capacitors 131 to 133 having a high series resonance frequency is used as the peaking capacitor. Can be used as

Further, the fitting of the feedthrough capacitor 134 shown in FIG. 14B is attached to the terminal 129 and the lead wire terminal 1
By short-circuiting 36 and 137 and connecting them to the terminal 130, they can be used as the above-mentioned peaking capacitor. The feedthrough capacitor is a pipe in which a lead wire penetrates and a capacitance is provided between the lead wire and the pipe.

Generally, a feedthrough capacitor has a characteristic that the series resonance frequency is extremely high due to the reduction of the lead wire, but the resonance frequency can be further increased by shorting the lead wire as shown in the figure. Further, either the lead terminal side or the fitting side may be used as the AC ground point side.

Further, as shown in FIG. 14 (a), a parallel combination capacitor may be used.
Further higher frequency is possible as shown in (d). Also, replace the feedthrough capacitor with a three-terminal capacitor,
Similar to the feedthrough capacitor, the resonance frequency can be increased when a two-terminal circuit in which conductive terminals are short-circuited is used as a peaking capacitor.

Next, in order to effectively operate as a peaking capacitor up to near the series resonance frequency, FIG.
As shown in (c) of FIG. 11, the series resistor 139 can be inserted to suppress the influence of resonance. Further, in order to more effectively perform peaking up to a higher frequency, a capacitor 142 having a higher resonance frequency than the capacitor 140 is added in parallel as shown in FIG.

Further, the circuit of (c) or (d) of FIG. 14 or the capacitor is connected between one terminal of the two terminals of the feedthrough capacitor which conducts and the terminal other than the two terminals which conduct. However, also when the capacitance between the other terminal of the above two terminals and the terminals other than the above two terminals which conducts is used as a peaking capacitor, the same effect as the above can be obtained.

An example of the peaking capacitor in this case is shown in FIG. Please also refer to FIG. 16, which is a circuit diagram showing another embodiment of the peaking capacitor. In FIG. 16, TEC indicates a three-terminal capacitor.

Next, FIG. 17 shows an embodiment in which the feedback impedance is connected to the low impedance terminal of the active element by using the above-mentioned second means so that the output signal can be fed back in a wide band as a current signal. .

In FIG. 17, by connecting the feedback impedance 7 to the emitter of the transistor 9, the output signal can be taken out in the positive phase from the collector of the transistor 9 as a broadband current signal. This is because at a low impedance terminal such as the emitter of the transistor 9, an increase in time constant due to the influence of various parasitic capacitances can be suppressed.

Further, the signal input from the terminal 2 to the base of the transistor 9 can be subtracted from the fed-back wide band current signal and can be taken out in the opposite phase from the collector of the transistor 9. The combined signal obtained from the collector of the transistor 9 is amplified by the inverting amplifier 143 and output from the terminal 5.

In particular, this embodiment is suitable when the output form of the inverting amplifier 143 is a dynamic load form consisting of a push-pull circuit with complementary active elements without using an output resistor. Because, as will be described later, by connecting the feedback impedance 7 to the output point that has become a high impedance due to the dynamic load type,
This is because a wider band can be achieved.

Next, FIG. 18 shows an embodiment in which the above-mentioned second means shown in FIG. 17 is realized by using an inverting amplifier having a push-pull circuit. In FIG. 18, the inverting amplifier is composed of a grounded-emitter circuit composed of transistors 16 and 35 whose bases are mutually coupled through a capacitor 34, and the output of which is an S composed of transistors 75 and 76.
It is output from the terminal 5 via the EPP.

At this time, the output is stabilized by the negative feedback via the feedback impedance 7. In FIG. 18, the connection point of the feedback impedance 7 for detecting the output voltage is provided in the collector of the transistor 35 to achieve a wider band as described later. However, if the output voltage appears, the connection of the feedback impedance 7 is performed. The point can be the emitter of the transistor 75, the terminal 5, or the like.

Further, a new signal current enhancing impedance is added between the emitter of the transistor 9 and a portion other than the connection point of the feedback impedance 7 for detecting the output voltage, such as an AC ground point. As a result, the voltage gain of the entire circuit can be increased. Bypass capacitor 144 supplies the signal current without bias impedance 91 to strongly drive the bases of transistors 75 and 76.

Next, FIG. 19 shows an embodiment in which further widening of the band is possible by using the above-mentioned second means. FIG. 19
In, the current signal is input from the signal current source 145 to the low impedance terminal of the active element 9 to which the feedback impedance 7 is connected via the terminal 2. By adopting the current input type, the frequency band in the signal input path can be expanded because of the characteristic that the low impedance terminal has a small time constant.

Further, in FIG. 19, since the transistor 9 is used in the base-grounded form, the influence of the Miller effect appearing at the input terminal 2 can be suppressed. Further, as shown in FIG. 19, in the signal source 146 using the signal current source 145, the signal source impedance is taken into consideration, or the input impedance 8 for voltage-current conversion is inserted in series, so that the signal voltage source 1 It goes without saying that the signal source 147 using is applicable. It goes without saying that a circuit of any system can be applied to the inverting amplifier 143.

FIG. 20 shows a skeleton of an embodiment characterized in that various peaking is applied to the embodiment shown in FIG. 19 to enable a wider band, and its practical circuit is shown in FIG. 20, reference numeral 143 denotes an inverting amplifier, which is composed of an inverting amplifier including the circuit shown in FIG.

In FIG. 21, similarly to the operation of the embodiment shown in FIG. 1, after the input signal is converted into a current through the transistor 148 and the input impedance 8, the feedback impedance 7 is generated by the negative feedback action of the amplifier in the subsequent stage. The voltage is inversely converted into an amplified voltage via the.

The various types of peaking shown will be described. The capacitor 149 and the resistor 150 enhance a high frequency component in the above current conversion, and the coil 152 is a parallel peaking element for suppressing band deterioration caused by parasitic capacitances of the transistors 9 and 12. Similarly, the capacitors 21 and 138, 159 are also peaking capacitors. The coils 166 and 168 and the damping resistors 167 and 169 are series peaking elements for suppressing the band deterioration caused by the parasitic capacitance of the transistors 75 and 76.

Next, various biasing diodes will be described. The diode 153 is used for biasing the transistor 12, and at the same time, it has an effect of reducing the time constant by suppressing the resistance value of the resistor 11 by using the bypass capacitor 154 together, thereby achieving a wider band. The Zener diode 155 grounds the base of the transistor 9 in an AC manner by the interaction with the bypass capacitor 157.
Diodes 160 to 162 are bypass capacitors 1
The interaction with 63 causes transistors 15 and 16 to
B-class bias.

Transistors 15 and 1 constituting SEPP
By supplying a sufficient bias current to the transistor 6, the switching speed of both transistors is increased to improve the drive capability of the base-grounded transistors 3 and 4 in the subsequent stage. Due to the functions of the diodes 84 and 85 and the bias resistor 170, the transistor 4 is biased to class AB and the transistor 22 is biased to class C.

The grounded base transistor 22 accelerates charging and discharging of the peaking capacitor 21 as described above, and enables strong peaking. Bypass capacitor 54
And 86 ground the transistor in alternating current. The diodes 90 and 92 and the bias resistor 91 bias the transistors 75 and 76 to class AB as described above.

Next, FIG. 22 shows the skeleton of the embodiment of the above-mentioned third means in which the feedback impedance is connected to the output signal detector showing a high impedance, and FIG. 23 shows its practical circuit. Show. In FIG. 22, CA is an impedance conversion amplifier, and the transistors 75 and 7 in FIG.
6, resistors 95, 96 and the like.

In FIG. 23, as the output signal appears, the feedback impedance 7 is connected to the interconnection point of the collectors of the transistors 16 and 35 exhibiting high impedance, and the terminal 5 is connected through the SEPP including the transistors 75 and 76. The output impedance of is reduced.

In the conventional amplifier circuit, in order to suppress the load effect of the feedback impedance, as shown by the broken line in FIG. 23, the feedback impedance 174 is eliminated and then the feedback impedance 174 is provided to the low impedance output terminal 5. It was common to connect. However, when the output point showing the high impedance is left as in the conventional case, the frequency characteristic of the open loop gain of the amplifier circuit is affected by the extremely large time constant at the output point, and the solid line in FIG. As indicated by 175, the gain in the low frequency range excessively increases.

In this way, when the height difference of the open loop gain is extremely large, no matter how negative feedback is applied to flatten the gain, as shown by a broken line 176 in FIG. The increase in the low frequency range cannot be suppressed. However, as in the embodiment of the present invention, the frequency characteristic of the open loop gain when the feedback impedance is connected to the output point exhibiting high impedance, since the time constant at the output point can be appropriately reduced, As indicated by the solid line 177 in FIG. 24B, the gain in the low frequency range can be suppressed to the necessary minimum level.

Therefore, by performing the negative feedback to further flatten the gain, the broken line 178 of FIG.
As shown in (4), the frequency characteristic of the closed loop gain is flattened, and the band of the amplifier circuit can be widened.

Further, in FIG. 23, the transistor 7
Although the output impedance of the terminal 5 is reduced by using SEPP composed of 5 and 76, in the present invention, the above S
It goes without saying that a buffer amplifier such as an emitter follower having a current amplification function can be applied without using the EPP. Further, the output point, which had a high impedance before connecting the feedback impedance, may be directly connected to the output terminal 5 without using the means corresponding to the buffer amplifier. In that case, the output impedance of the amplifier circuit is reduced by the action of negative feedback.

As described above, the embodiment in which the feedback impedance is connected to the output signal detector showing the high impedance is as follows.
It has already been shown in FIGS. 13, 18 and 21. FIG. 25 shows a skeleton of an embodiment of a positive phase amplifier in which the present invention is applied and the peaking is strengthened, and FIG. 26 shows a practical circuit thereof. In FIG. 25, CA is an impedance conversion amplifier and 143 is an inverting amplifier.

In FIG. 26, the feedback impedance 7
Since the emitter of the transistor 16 is series-fed back via the, the input impedance of the amplifier circuit can be increased. Further, the capacitor 21 has a function of limiting the frequency band in order to stabilize the negative feedback.

The DC gain of this embodiment is determined by the resistance ratio of the resistor 179 and the feedback impedance 27. Capacitor 37 and coils 166 and 168 are also used for peaking, similar to the elements described above.

Next, FIG. 27 shows a skeleton of an embodiment in which a wide band can be achieved by transmitting a current signal from the DC region in a push-pull format by using a circuit configuration with a small number of elements. The circuit is shown in FIG.

In FIG. 28, the signal voltage appearing at the input terminal 2 is applied from the DC region to the base of the transistor 16 and also to the base of the transistor 35 via the impedance 181 to reduce the output voltage of the output transistor 2.
Push-pull operation is possible only by using the element.

In this case, it is considered that the current component of the input signal is shunted to the bases of the transistors 16 and 35 via the impedance network. Further, the high-frequency component of the signal voltage appearing at the input terminal 2 is added to the base of the transistor 35 by being emphasized more than the DC component by passing through the bypass capacitor 34.

The output transistors 16 and 35 described above are also provided.
The base drive voltage of is not subject to amplitude limits as when the input signal is a voltage signal. Therefore, the gain frequency bandwidth product of the open loop gain of the circuit increases. As a result, the current signal from the signal current source 145 is fed back into the feedback impedance 7
The voltage is converted into a wide band voltage via and appears at the output terminal 5.
The capacitors 32 and 37 are peaking elements, but needless to say, can be deleted. Similarly, it goes without saying that the effect of the present invention can be obtained even if the bypass capacitor 34 is deleted.

Furthermore, as shown in FIG. 19, the signal current source 145 can be replaced with a signal voltage source whose input impedance is connected in series. 29, FIG. 30, FIG. 31, FIG. 29, and FIG. 29 are schematic views of a practical embodiment that enables a wider band by efficiently transmitting a current signal from a DC region to a high frequency region in a push-pull format. 33 and their practical circuit is shown in FIG. In FIG. 33, reference numeral 183 denotes an integrated circuit.

In FIG. 34, the power supply 10 converts the voltage signal input to the terminal 191 of the integrated circuit 183 having a relatively low voltage into a current signal, and then the grounded base transistor 184.
Input to the amplifier circuit section having a high power supply voltage. Therefore, by interposing the transistor 184 between the high voltage section and the high voltage section, it is possible to use the semiconductor integrated circuit 183 or the like, which can easily realize wide band characteristics, without fear of destruction due to excess withstand voltage.

In the amplifier circuit section, as in FIG. 28,
The current signal is converted into an output voltage signal via the feedback impedance 7. At this time, the above-mentioned current signal is not wasted as the base drive current of the output transistors 16 and 35 that increase at high frequencies, but is efficiently supplied to the feedback impedance 7 so that the transistors 185 and 18 are provided.
SEPP consisting of 6 is used.

Diodes 48 and 49 and resistors 198 and 199 are used to set the bias of the SEPP, and a capacitor 50 is used to bypass the signal current and obtain a stable bias voltage. Also,
The output voltage of the SEPP composed of the transistors 185 and 186 is converted into impedances 180 and 187 and 182 and 18
By dividing the voltage via 9, the output transistor 16
And 35 are obtained as base driving voltages.

Bypass capacitors 188 and 190 enhance the above base drive voltage at high frequencies. Resistors 195 and 1 inserted in series at the base of each transistor
It goes without saying that 96 and 197, 112, 200, 93, and 94 are stabilizing resistors for preventing oscillation.

Next, FIG. 3 shows an embodiment in which the "diamond circuit" shown in FIG. 13 can be applied to wideband signals.
5 shows. The transistors 202 and 203 in FIG. 35 are an emitter follower circuit for driving the SEPP which is composed of the transistors 75 and 76 in the subsequent stage, and at the same time have the functions of a bias setting circuit for the transistors 75 and 76.

However, in the conventional "diamond circuit", the sum of the base-collector parasitic capacitances of the transistors 109 and 110 which form the former stage emitter follower circuit shown in FIG. The high input impedance originally required for an amplifier cannot be obtained.

In particular, in the case where the preceding stage of the "diamond circuit" is a circuit having a relatively high output impedance as represented by a dynamic load type, it is often impossible to secure a sufficient frequency band due to the heavy load. .
In FIG. 35 showing the present embodiment, by connecting the collectors of the transistors 202 and 203 constituting the emitter-follower circuit of the preceding stage to the output of SEPP of the succeeding stage, a high input impedance originally required as a buffer amplifier is secured. ing.

That is, by applying a signal substantially equal to the signal input to the base to the collector of the transistor which constitutes the emitter follower circuit of the previous stage, the current flowing in the parasitic capacitance between the base and collector is suppressed and the input capacitance is reduced. Has been reduced. The feature of the embodiment shown in FIG. 35 is that the bias voltage source 201 and the emitter resistor 9
By the action of 5 and 96, the SEPP of the latter stage is classified as A grade or A
That is, it is possible to apply a sufficient bias current to the constituent transistors 75 and 76 by biasing to the class B, and to realize a high speed and wide band.

On the contrary, the polarity of the bias voltage source 201 may be reversed to bias the SEPP in the subsequent stage to class C, thereby reducing the power consumption of the circuit. In order to improve the accuracy and stabilize the bias setting, it is preferable that the transistors 202 and 203 are biased by the constant current sources 204 and 205 as illustrated. However, it goes without saying that the constant current sources 204 and 205 described above can be replaced with resistors or other impedances.

Further, the transistors 75 and 76, when the large amplitude operation, the electrostatic discharge, the discharge of the load picture tube, etc.
It goes without saying that a protection diode can be added in parallel between the base and emitter of each transistor so that a reverse voltage exceeding the breakdown voltage is not applied between the base and emitter of 202 and 203.

Please refer to FIG. 36, which is a modification of the embodiment of FIG. Next, FIG. 37 shows an embodiment in which the "diamond circuit" of the present invention is applied to the buffer amplifier at the final stage of the amplifier circuit.

Also in FIG. 37, the current signal input to the terminal 2 is converted into the output voltage signal via the feedback impedance 7 by the negative feedback operation of the circuit. Also in FIG. 37, the collectors of the transistors 202 and 203 constituting the emitter follower circuit of the former stage are connected to the SEP of the latter stage.
The output of P is connected to the emitters of transistors 76 and 75, respectively.

The feature of the embodiment shown in FIG. 37 is that the emitters of the transistors 202 and 203 are connected via a capacitor 206, so that the SEP in the subsequent stage is connected.
That is, the drive capability of the transistors 76 and 75 forming P is improved. Both bases of transistors 76 and 75 are driven by transistors 203 and 202, respectively, at the rising and falling edges of the output voltage signal.

Further, the stabilizing resistor 207 is connected to the capacitor 20.
By connecting in series with 6, the transistors 202 and 2
Oscillation due to the coupling of the 03 emitter is suppressed. Similarly, the base resistors 212 and 213 also suppress the oscillation of the transistors 202 and 203. Also, as in the description of the embodiment shown in FIG.
1 is used to protect the transistors 202 and 203. Further, it goes without saying that the biasing resistance 91 of the transistors 76 and 75 which form the SEPP in the latter stage can be replaced with a constant voltage element such as a diode or a circuit, or a bypass capacitor can be added in parallel.

Please refer to FIG. 38, which is a circuit diagram showing the skeleton of the embodiment shown in FIG. Next, FIG. 39 shows an embodiment of the "diamond circuit" of the present invention capable of further widening the band.

In FIG. 39, the bases of the transistors 202 and 203 forming the emitter follower circuit of the preceding stage can be connected to each other without a bias voltage source. Therefore,
Since the number of elements connected to the input terminals of the "diamond circuit" can be reduced to the maximum, the high input impedance originally required for a buffer amplifier can be obtained.

In addition, the coil 214 and the damping resistor 2
A wider band can be achieved by using a single peaking circuit consisting of 15. Further, by adding a signal substantially equal to the input to the collectors of the transistors 202 and 203 that form the emitter follower circuit through the bypass capacitor 220 and the transistor 221, the bypass capacitor 217 and the transistor 218, respectively, the input impedance is increased. I am trying.

At this time, the bias impedance 216
And 219 respectively, the currents of the current sources 204 and 205 are applied to set the bias voltage between the base and collector of the transistors 202 and 203, respectively.
The saturation of 02 and 203 is prevented, the parasitic capacitance itself is reduced, and the transient frequency is increased. The current sources 204 and 205 can be replaced with arbitrary elements or circuits such as resistors as long as they can pass a bias current.

Similarly, the bias impedance 216
As for 219 and 219, any element or circuit such as a diode or a voltage source circuit can be substituted as long as it can generate a bias voltage. In addition, the transistor 7 that constitutes the SEPP in the subsequent stage
It goes without saying that the bias currents of the transistors 75 and 76 can be arbitrarily set by connecting the bases of 5 and 76 to the bases of either of the transistors 218 and 221 respectively.

FIG. 40 shows an embodiment of the "diamond circuit" of the present invention, which enables higher speed and wider bandwidth. In this embodiment, the emitters of the transistors forming the emitter follower circuit in the former stage are connected to the SE in the latter stage.
The drive capability of the load is improved by connecting the bases of the elements of the same polarity to the respective transistors forming the PP.

The emitters of the transistors 202 and 203 forming the above-mentioned former emitter follower circuit in FIG. 40 are connected to transistors 76 and 75 of the same polarity through coupling capacitors 222 and 223, respectively. Since the base resistances 94 and 93 are stabilizing resistances as described above, they are suppressed to a relatively low value. Two sets of the same polarity transistors 202 and 7 connected in cascade as described above.
In Nos. 6 and 203 and 75, the drive speed of the load can be maximized by increasing the emitter currents of both of them at the fall and rise of the signal voltage in the forward direction.

Here, the coupling between the emitters of the transistors 202 and 203 can be suppressed without interfering with the driving capability of the subsequent stage by interposing the impedances 224 and 225 for transmitting DC. Further, similarly to the embodiment shown in FIG. 39, in this embodiment as well, the number of elements connected to the input terminals can be reduced to the maximum, so that the high input impedance originally necessary for the buffer amplifier can be obtained.

It goes without saying that the impedances 216 and 226 and 219 and 227 are used for setting the bias currents of the transistors 75 and 76 and the collector bias voltage of the transistors 203 and 202. Further, it goes without saying that the bypass capacitors 217 and 220 can be deleted.

Further, in FIG. 40, the transistor 2
The collector of 02 is removed from the emitter of the transistor 76 and is connected to an AC grounding point such as a grounding point to connect the transistor 2
Needless to say, even if the collector of 03 is removed from the emitter of the transistor 75 and connected to an AC grounding point such as the anode of the power supply 24, the above-described speed-up effect can be obtained. Figure 41
FIG. 3 is a circuit diagram showing such an embodiment. In addition, FIG.
Please refer to FIG. 39, which is a circuit diagram showing the skeleton of the embodiment.

Finally, FIGS. 44 and 45 show embodiments of the present invention using a serial-parallel peaking circuit using a coil, respectively. The feature of this embodiment is that the damping, which was conventionally performed by newly adding a resistor that consumes power, is performed by using the existing output resistor via the capacitor, thereby enabling a wider band. There is a point.

FIG. 43 is a circuit diagram showing a conventional grounded-emitter amplifier circuit. The output frequency band of this grounded-emitter amplifier circuit is obtained from the capacitance on the collector side of the transistor 16 including the output resistor 33 and the load capacitance 6. It is limited by being inversely proportional to the time constant on the output side. Therefore, a parallel peaking coil 74 that causes parallel resonance with the collector-side capacitance in order to expand the output frequency band,
It has been common in the past to insert the series peaking coil 102 that causes series resonance as shown.

The series peaking coil 102 is once removed from the circuit in the figure, and then the collector of the transistor 16 is connected to the output of the transistor 16 by connecting the collector of the transistor 16 to the terminal of the coil 74 which is not connected to the output resistor 33. It can also be inserted in series with the terminal 5. In order to flatten the frequency characteristic of the amplifier circuit, damping by the output resistance 33 naturally works against the resonance of the coil 74, so that it is only necessary to adjust the inductance, but for the coil 102, damping resistance. It is necessary to add 103 in parallel.

However, when both the flattening of the frequency characteristic and the band expansion are made compatible with each other, the Q of resonance should be reduced to sufficiently expand the output frequency band due to the influence of the resonance energy consumption in the resistor 103. I can't. In the embodiment of the present invention shown in FIG. 44, the coil 74 for parallel peaking and the coil 1 for series peaking are connected to each other.
A coupling capacitor 228 is connected in parallel between the above-mentioned non-interconnected terminals of No. 02.

In addition to allowing the output signal current of the transistor 16 to flow through the existing output resistor 33 via the capacitor 228, the output resistor 33 can also be used for damping the series resonance described above. It will be possible. Further, the coil 102 for series peaking is removed from the circuit in the drawing once, as in the case of FIG.
It is also possible to connect the collector of the transistor 16 to the terminal of the coil 74 that is not connected to the output resistor 33 and insert the transistor 16 in series between the collector of the transistor 16 and the output terminal 5.

Also in this case, the coil 74 for parallel peaking and the coil 102 for series peaking connected to each other.
By connecting the coupling capacitor 228 in parallel between the terminals not connected to each other, the same effect as described above can be obtained.

Further, in addition to the circuit configuration shown in FIG. 44, another series peaking coil can be inserted in series between the connection point of the coils 74 and 102 and the output terminal 5. In that case, this corresponds to dividing the series peaking coil, and the peaking can be optimized corresponding to the ratio of the parasitic capacitance and the load capacitance on the collector side of the transistor 16.

As shown in FIG. 45, the same effect can be obtained even if the grounded base transistor 3 for grounding the base in AC and inputting a signal to the emitter is inserted in the subsequent stage of the transistor 16. Not to mention.

FIG. 46 is a circuit diagram showing an embodiment in which the periphery of the wide band amplifier circuit is shielded by the conductor plate LP in the embodiment of FIG. 27 to suppress unnecessary radiation from the wide band amplifier circuit. Please refer.

Although the embodiments have been described using transistors as active elements, it goes without saying that semiconductor elements such as FETs and any active elements such as vacuum tubes can also be applied. It goes without saying that the polarities of the active elements, the voltage sources, and the current sources can be reversed.

When a picture tube is assumed as the load, a monochrome picture display, a projection type display, a monochromatic tube used for an oscilloscope, and a color picture tube having a plurality of drive electrodes used for a color display or the like. Alternatively, any display element such as a plasma display panel or a liquid crystal display panel can be used.

Further, as the driving electrodes, all kinds of electrodes to which signals such as a cathode, each grid and an anode are inputted can be considered. Further, the embodiments of the present invention can be applied not only to the picture tube but also to a general wide band signal amplifying circuit which drives an arbitrary load and an arbitrary signal processing circuit which handles a signal.

[0133]

As described above, according to the present invention,
It is possible to provide a wideband amplifier circuit capable of outputting a large-amplitude wideband signal without increasing power consumption. Therefore, by using the present invention, a wide-band, large-amplitude picture tube drive circuit having a bandwidth of about 50 MHz to 300 MHz and an output amplitude of about 30 V to 50 V applicable to a computer display for CAD / CAM, etc. It can be realized by a circuit form of a scale. Therefore, it becomes easy to cover and shield with the shield plate of the entire amplifier circuit, and unnecessary radiation can be reduced.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a basic embodiment of a wideband amplifier circuit of the present invention.

FIG. 2 is a circuit diagram showing a conventional capacitive load drive circuit.

FIG. 3 is a circuit diagram showing another embodiment of the present invention.

FIG. 4 is a circuit diagram showing another embodiment of the present invention.

FIG. 5 is a circuit diagram showing another basic embodiment of the present invention.

FIG. 6 is a circuit diagram showing another basic embodiment of the present invention.

FIG. 7 is a circuit diagram showing still another basic embodiment of the present invention.

FIG. 8 is a circuit diagram showing a practical embodiment of the present invention.

FIG. 9 is a circuit diagram showing various elements and circuits that can be used in an embodiment of the present invention.

FIG. 10 is a circuit diagram showing a skeleton of still another embodiment of the present invention.

FIG. 11 is a circuit diagram showing a practical embodiment of the present invention. .

FIG. 12 is a circuit diagram showing a skeleton of another embodiment of the present invention.

FIG. 13 is a circuit diagram showing a practical embodiment of the present invention.

FIG. 14 is a circuit diagram showing an embodiment of a peaking capacitor used in the broadband amplifier circuit of the present invention.

FIG. 15 is a circuit diagram showing an embodiment of another peaking capacitor used in the broadband amplifier circuit of the present invention.

FIG. 16 is a circuit diagram showing an embodiment of another peaking capacitor used in the broadband amplifier circuit of the present invention.

FIG. 17 is a circuit diagram showing another embodiment of the present invention.

FIG. 18 is a circuit diagram showing a practical embodiment of the present invention.

FIG. 19 is a circuit diagram showing another embodiment of the present invention.

FIG. 20 is a circuit diagram showing a skeleton of another embodiment of the present invention.

FIG. 21 is a circuit diagram showing a practical embodiment of the present invention.

FIG. 22 is a circuit diagram showing a skeleton of another embodiment of the present invention.

FIG. 23 is a circuit diagram showing a practical embodiment of the present invention.

FIG. 24 is a characteristic diagram showing the effect of the embodiment of the present invention.

FIG. 25 is a circuit diagram showing a skeleton of another embodiment of the present invention.

FIG. 26 is a circuit diagram showing a practical embodiment of the present invention.

FIG. 27 is a circuit diagram showing a skeleton of still another embodiment of the present invention.

FIG. 28 is a circuit diagram showing a practical embodiment of the present invention.

FIG. 29 is a circuit diagram showing a skeleton of still another embodiment of the present invention.

FIG. 30 is a circuit diagram showing a skeleton of still another embodiment of the present invention.

FIG. 31 is a circuit diagram showing a skeleton of still another embodiment of the present invention.

FIG. 32 is a circuit diagram showing a skeleton of still another embodiment of the present invention.

FIG. 33 is a circuit diagram showing a skeleton of still another embodiment of the present invention.

FIG. 34 is a circuit diagram showing a practical example of the present invention.

FIG. 35 is a circuit diagram showing a skeleton of still another embodiment of the present invention.

FIG. 36 is a circuit diagram showing a skeleton of still another embodiment of the present invention.

FIG. 37 is a circuit diagram showing a skeleton of a practical example of the present invention.

FIG. 38 is a circuit diagram showing a skeleton of another embodiment of the present invention.

FIG. 39 is a circuit diagram showing a practical embodiment of the present invention.

FIG. 40 is a circuit diagram showing a practical embodiment of the present invention.

FIG. 41 is a circuit diagram showing a skeleton of still another embodiment of the present invention.

FIG. 42 is a circuit diagram showing a skeleton of still another embodiment of the present invention.

FIG. 43 is a circuit diagram showing a conventional grounded-emitter amplifier circuit.

FIG. 44 is a circuit diagram showing an example of the present invention.

FIG. 45 is a circuit diagram showing an embodiment of the present invention.

FIG. 46 is a circuit diagram showing another embodiment of the present invention.

FIG. 47 is a circuit diagram showing a circuit in which a transistor of each polarity and an FET correspond to each other.

[Explanation of symbols]

1 ... Signal voltage source, 2 ... input terminal, 3 ... output transistor (NPN), 4 ... output transistor (PNP), 5 ... output terminal, 6 ... load capacitance, 7 ... feedback impedance

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Michitaka Osawa, 292 Yoshida-cho, Totsuka-ku, Yokohama, Kanagawa Prefecture

Claims (28)

[Claims] 1. An amplifier circuit including a push-pull circuit, comprising two active elements (1
5, 16), two of the interconnection points of the electrodes are connected to each other by connecting one to the input side (2) and the other to the peaking capacitor (32) used as a terminal for gain setting. A broadband amplifier circuit (FIG. 3) characterized in that at least one of the remaining two electrodes is the output side (5). 2. In an amplifier circuit including a push-pull circuit, the first and second two transistors (16, 15) forming the push-pull circuit have a first base or a gate of the transistor. When the electrode, the emitter or the source is the second electrode and the collector or the drain is the third electrode, it is connected to the second electrode of the first transistor (16) having the first electrode connected to the input side (2). , A peaking capacitor (32) is connected, and a second transistor (15) having a polarity opposite to that of the first transistor (16) is connected to the second transistor (15).
Of the second transistor (15), the first electrode of the second transistor (15) is connected to the input side (2), and the third electrode of the first transistor (16) is connected to the output side (5). Wideband amplifier circuit (Fig. 3) characterized by being connected to. 3. An amplifier circuit including a push-pull circuit, wherein for each of the first and second two transistors (16, 15) forming the push-pull circuit, the base or gate of the transistor is the first. When the electrode, the emitter or the source is the second electrode and the collector or the drain is the third electrode, it is connected to the second electrode of the first transistor (16) having the first electrode connected to the input side (2). , A peaking capacitor (32) is connected, and a second transistor (15) having a polarity opposite to that of the first transistor (16) is connected to the second transistor (15).
Of the second transistor (15), the first electrode of the second transistor (15) is connected to the input side (2), and the third electrode of the first transistor (16) is connected to the output side (5). And an input terminal (I) of the first current mirror circuit (CM1) to the third electrode of the second transistor (15), and the output of the first current mirror circuit (CM1). The input terminal (I) of the second current mirror circuit (CM2) is connected to the terminal (O), and the output side (5) is connected to the output terminal (O) of the second current mirror circuit (CM2). A wide-band amplifier circuit characterized by being formed (FIG. 12). 4. In an amplifier circuit including a push-pull circuit, a base or a gate of the transistor is provided as a first with respect to two third and fourth transistors (3, 73) forming the push-pull circuit. When the electrode, the emitter or the source is the second electrode and the collector or the drain is the third electrode, one terminal of the peaking capacitor (70) is connected to the input side (2), and the peaking capacitor (70) is connected. The other terminal of the peaking capacitor is connected to the second electrode of the third transistor (3), and the peaking capacitor (70) is connected.
The other side of the third transistor (3) has a polarity opposite to that of the fourth transistor (3).
The second electrode of the third transistor (73), the first electrode of the third transistor (3) and the first electrode of the fourth transistor (73) are connected to each other, and The third electrode of the third transistor (3) is connected to the output side (5).
A wide-band amplifier circuit (Fig. 1)
0). 5. An amplifier circuit including a push-pull circuit, wherein a fifth transistor (4) is provided in addition to the first and second two transistors (16, 15) forming the push-pull circuit. When the base or gate of the transistor is the first electrode, the emitter or the source is the second electrode, and the collector or the drain is the third electrode, the first electrode is connected to the input side (2). The peaking capacitor (32) is connected to the second electrode of the first transistor (16) connected to the second transistor (15) and the second transistor (15) having the opposite polarity to the first transistor (16).
Of the second transistor (15), the first electrode of the second transistor (15) is connected to the input side (2), and the third electrode of the first transistor (16) is connected to the output side (5). Further, the third electrode of the second transistor (15) is connected to the second electrode of the fifth transistor (4) via the capacitor (60), and the fifth transistor (4) is connected to the third electrode of the fifth transistor (4). And a third electrode of the first transistor (16) connected to the third electrode of the broadband amplifier circuit (FIG. 5). 6. An amplifier circuit including a push-pull circuit, wherein a fifth transistor (4) is provided in addition to the first and second two transistors (16, 15) forming the push-pull circuit. When the base or gate of the transistor is the first electrode, the emitter or the source is the second electrode, and the collector or the drain is the third electrode, the first electrode is connected to the input side (2). The peaking capacitor (32) is connected to the second electrode of the first transistor (16) connected to the second transistor (15) and the second transistor (15) having the opposite polarity to the first transistor (16).
Of the second transistor (15), the first electrode of the second transistor (15) is connected to the input side (2), and the third electrode of the first transistor (16) is connected to the output side (5). Further, the third electrode of the second transistor (15) is connected to the second electrode of the fifth transistor (4) through a constant voltage circuit or element (45), The third electrode of the transistor (4) is connected to the first transistor (16).
A wide-band amplifier circuit (FIG. 6), characterized in that it is connected to the third electrode of FIG. 7. An amplifier circuit including a push-pull circuit, wherein a fifth transistor (4) is provided in addition to the first and second two transistors (16, 15) forming the push-pull circuit. When the base or gate of the transistor is the first electrode, the emitter or the source is the second electrode, and the collector or the drain is the third electrode, the first electrode is connected to the input side (2). The peaking capacitor (32) is connected to the second electrode of the first transistor (16) connected to the second transistor (15) and the second transistor (15) having the opposite polarity to the first transistor (16).
Of the second transistor (15), the first electrode of the second transistor (15) is connected to the input side (2), and the third electrode of the first transistor (16) is connected to the output side (5). Further, the third electrode of the second transistor (15) is connected to the second electrode of the fifth transistor (4) via the capacitor (60), and the fifth transistor (4) is connected to the third electrode of the fifth transistor (4). The third electrode of the first transistor (16) is connected to the third electrode of the first transistor (16), and the third electrode of the second transistor (15) has a high impedance such as a constant current circuit or a coil. A wideband amplifier circuit (Fig. 7), characterized in that it comprises possible circuits (46). 8. A feedthrough capacitor having a capacitance between the pipe and a lead wire penetrating the pipe.
At both ends of the lead wire (1
36, 137) is short-circuited outside the pipe to form the first terminal (130), and the pipe side is the second terminal (135).
As a capacitor, the capacitor capacity is taken out from both terminals (b in FIG. 14). 9. A feedthrough capacitor having a capacitance between a pipe and a lead wire penetrating the pipe.
At both ends of the lead wire (1
36, 137) is used as the first terminal (130) of either (136) and both ends (136, 13) of the lead wire.
A capacitor (142) is connected between the other end (137) of 7) and the pipe side terminal (135), and the pipe side terminal (135) is used as a second terminal (129). First terminal (130) and second terminal (129)
A capacitor characterized in that the capacitance is taken out from between (FIG. 15). 10. Out of the two terminals for taking out the capacitance of the capacitor, one terminal is branched to form two terminals (136, 1).
37), a three-terminal capacitor (TEC) having a three-terminal configuration is obtained by short-circuiting and connecting the two terminals (136, 137) that are branched into two terminals with a lead wire. ), And the other terminal (135) of the two terminals for taking out the capacitance of the capacitor is a second terminal (129), and a capacitance from between the first terminal (130) and the second terminal (129). To take out the capacitor (FIG. 16). 11. An amplifier circuit including a sixth transistor (9), wherein the base or gate of the transistor is a first electrode, the emitter or source is a second electrode, and the collector or drain is a third electrode. In this case, one terminal of the feedback impedance (7) is connected to the second electrode of the sixth transistor (9) whose first electrode is connected to the input side (2), and the feedback impedance (7) is connected. The other terminal of the inverting amplifier (143) is connected to the output side (5), and the input side of the inverting amplifier (143) is connected to the third side of the sixth transistor (9). A wide-band amplifier circuit (Fig. 17) characterized by being connected to the electrodes of. 12. An amplifier circuit including a sixth transistor (9), wherein the base or gate of the transistor is a first electrode, the emitter or source is a second electrode, and the collector or drain is a third electrode. In this case, the input side (2) is connected to the second electrode of the sixth transistor (9) and one terminal of the feedback impedance (7) is connected, and the other terminal of the feedback impedance (7) is connected. Is connected to the output side (5) and is also connected to the output side of the inverting amplifier (143).
43) the third side of the sixth transistor (9) is connected to the input side.
A wide-band amplifier circuit (Fig. 19) characterized in that the electrodes of are connected. 13. The wideband amplifier circuit according to claim 12, wherein the inverting amplifier (143) includes the wideband amplifier circuit according to claim 4. 14. A feedback impedance (7) is connected between an input terminal and an output terminal of an inverting amplifier (143), and an output terminal of the inverting amplifier (143) is output side via an impedance conversion amplifier (CA). And an input terminal of the inverting amplifier (143) on the input side, the wide band amplifier circuit (FIG. 22). 15. An amplifier circuit including a seventh transistor (16), wherein the base or gate of the transistor is a first electrode, the emitter or source is a second electrode, and the collector or drain is a third electrode. Then, one terminal of the feedback impedance (7) is connected to the second electrode of the seventh transistor (16) whose first electrode is connected to the input side (2), and the seventh transistor (16) The other terminal of the feedback impedance (7) is connected to the third electrode of 16) via the inverting amplifier (143), and the other terminal of the feedback impedance (7) is connected to the impedance conversion amplifier (CA). A wide-band amplifier circuit (FIG. 25) characterized in that an input terminal is connected and an output terminal of the impedance conversion amplifier (CA) is connected to an output side (5). 16. An amplifier circuit comprising an eighth transistor (16) and a ninth transistor (35), the base or gate of the transistor being the first electrode, the emitter or source being the second electrode, and the collector. Alternatively, when the drain is the third electrode, the first electrode of the eighth transistor (16) is connected to the input side (2), and the ninth electrode having a polarity opposite to that of the eighth transistor (16) is used. The first electrode of the transistor (35) is connected, and also one terminal of the feedback impedance (7) is connected, and the third electrode of the eighth transistor (16) and the ninth transistor (35) are connected. And the feedback impedance (7).
The other terminal of the eighth transistor (1
The interconnection point between the third electrode of 6), the third electrode of the ninth transistor (35) and the other terminal of the feedback impedance (7) is connected to the output side (5). Characteristic wideband amplifier circuit (Fig. 27). 17. An amplifier circuit comprising an eighth transistor (16) and a ninth transistor (35), the base or gate of the transistor being the first electrode, the emitter or source being the second electrode, and the collector. Alternatively, when the drain is the third electrode, the first DC coupling circuit (1) including a resistor or the like is provided between the input side (2) and the first electrode of the eighth transistor (16).
89) and is connected to the input side (2) and the eighth
Is connected to the first electrode of the ninth transistor (35) having the opposite polarity via the second DC coupling circuit (187) including a resistor and the feedback impedance (7). 1) is connected to the input side (2), the third electrode of the eighth transistor (16) and the third electrode of the ninth transistor (35) are connected to each other, and The other terminal of the feedback impedance (7) is also connected to the third electrode of the eighth transistor (16), the third electrode of the ninth transistor (35) and the other terminal of the feedback impedance (7). A broadband amplifier circuit (FIG. 29), characterized in that an interconnection point with the terminal of is connected to the output side (5). 18. An amplifier circuit comprising an eighth transistor (16) and a ninth transistor (35), the base or gate of the transistor being the first electrode, the emitter or source being the second electrode, and the collector. Alternatively, when the drain is the third electrode, the first direct-current coupling including the buffer amplifier (BA) and the resistor is provided between the input side (2) and the first electrode of the eighth transistor (16). The buffer amplifier connected between the input side (2) and the first electrode of the ninth transistor (35) having a polarity opposite to that of the eighth transistor (16) and connected via a circuit (189). Second consisting of (BA) and resistance
Of the feedback impedance (7) and the third electrode of the eighth transistor (16) and the ninth electrode of the eighth transistor (16). The third electrode of the transistor (35) of the second transistor (35) is connected to each other, and the other terminal of the feedback impedance (7) is also connected to the eighth transistor (16).
The third electrode of the third transistor of the ninth transistor (35)
A wide-band amplifier circuit (FIG. 30), characterized in that an interconnection point between the electrode of (1) and the other terminal of the feedback impedance (7) is connected to the output side (5). 19. The wide band amplifier circuit according to claim 18, wherein a signal current source (145) is connected to the input side (2). 20. The broadband amplifier circuit according to claim 19, wherein the signal current source (145) is connected to the input side (10) via a tenth transistor (184) having a first electrode grounded. Wideband amplifier circuit (Fig. 32) characterized by being connected to 2). 21. The wide band amplifier circuit according to claim 20, wherein the signal current source is constituted by an integrated circuit (183). 22. An amplifier circuit comprising an eleventh transistor (202), a twelfth transistor (203), a thirteenth transistor (75) and a fourteenth transistor (76), the base or When the gate is the first electrode, the emitter or source is the second electrode, and the collector or drain is the third electrode, the first electrode of the eleventh transistor (202) is connected to the input side (2). At the same time, a twelfth transistor (20) having a polarity opposite to that of the eleventh transistor (202).
3) The first electrode is connected to the second electrode of the eleventh transistor (202), and the first electrode of the thirteenth transistor (75) having a polarity opposite to that of the eleventh transistor (202). Is connected to the second electrode of the twelfth transistor (203),
A fourteenth transistor having a polarity opposite to that of the twelfth transistor (203).
Connected to the first electrode of the transistor (76), connected to the third electrode of the eleventh transistor (202) to the second electrode of the fourteenth transistor (76), The second electrode of the thirteenth transistor (75) is connected to the third electrode of the transistor (203), and the second electrode of the thirteenth transistor (75) and the fourteenth transistor (76) are connected. A wide-band amplifier circuit (FIG. 36), characterized in that the second electrode and the second electrode are respectively connected to the output side (5). 23. An amplifier circuit comprising an eleventh transistor (202), a twelfth transistor (203), a thirteenth transistor (75) and a fourteenth transistor (76), the base or When the gate is the first electrode, the emitter or source is the second electrode, and the collector or drain is the third electrode, the first side of the twelfth transistor (203) is provided on the input side (2).
Of the twelfth transistor (2
03) and the eleventh transistor (20
2) the first electrode and the twelfth transistor (20
Bias voltage generating circuit (2
01) is connected to the eleventh transistor (202)
The eleventh transistor (202) on the second electrode of the
To the second electrode of the twelfth transistor (203), the first electrode of the thirteenth transistor (75) having the opposite polarity to
A fourteenth transistor having a polarity opposite to that of the twelfth transistor (203).
Connected to the first electrode of the transistor (76), connected to the third electrode of the eleventh transistor (202) to the second electrode of the fourteenth transistor (76), The second electrode of the thirteenth transistor (75) is connected to the third electrode of the transistor (203), and the second electrode of the thirteenth transistor (75) and the fourteenth transistor (76) are connected. A wide band amplifier circuit (FIG. 35), characterized in that the second electrode is connected to the output side (5) via impedance elements (95, 96), respectively. 24. An amplifier circuit comprising an eleventh transistor (202), a twelfth transistor (203), a thirteenth transistor (75) and a fourteenth transistor (76), the base or When the gate is the first electrode, the emitter or source is the second electrode, and the collector or drain is the third electrode, the first electrode of the eleventh transistor (202) is connected to the input side (2). At the same time, a twelfth transistor (20) having a polarity opposite to that of the eleventh transistor (202).
3) is also connected to the first electrode, and the second electrode of the eleventh transistor (202) has a thirteenth transistor (75) having a polarity opposite to that of the eleventh transistor (202).
To the second electrode of the twelfth transistor (203),
A fourteenth transistor having a polarity opposite to that of the twelfth transistor (203).
Connected to the first electrode of the transistor (76), connected to the third electrode of the eleventh transistor (202) to the second electrode of the fourteenth transistor (76), The second electrode of the thirteenth transistor (75) is connected to the third electrode of the transistor (203), and the second electrode of the eleventh transistor (202) is connected to the third electrode via a capacitor (223). 14 transistors (76) connected to the first electrode, and the twelfth transistor (203) second electrode to the first electrode of the thirteenth transistor (75) via a capacitor (222). And a second electrode of the thirteenth transistor (75) and a second electrode of the fourteenth transistor (76) respectively connected to the output side (5). Road (Fig. 38). 25. In an amplifier circuit including an eleventh transistor (202), a twelfth transistor (203), a thirteenth transistor (75) and a fourteenth transistor (76), the base or When the gate is the first electrode, the emitter or source is the second electrode, and the collector or drain is the third electrode, the first electrode of the eleventh transistor (202) is connected to the input side (2). At the same time, a twelfth transistor (20) having a polarity opposite to that of the eleventh transistor (202).
3) is also connected to the first electrode, and the second electrode of the eleventh transistor (202) has a thirteenth transistor (75) having a polarity opposite to that of the eleventh transistor (202).
To the second electrode of the twelfth transistor (203) by connecting the first electrode of
A fourteenth transistor having a polarity opposite to that of the twelfth transistor (203).
The first electrode of the transistor (76) of
5) and the eleventh transistor (20
The second electrode of (2) is connected to the first AC ground point, the third electrode of the twelfth transistor (203) is connected to the second AC ground point, and the eleventh transistor ( 202) is connected to the first electrode of the fourteenth transistor (76) via a capacitor (223), and the second electrode of the twelfth transistor (203) is connected to the thirteenth electrode. Connected to the first electrode of the transistor (75) via a capacitor (222), and connecting the second electrode of the thirteenth transistor (75) and the second electrode of the fourteenth transistor (76). A wide-band amplifier circuit (Fig. 41) characterized by being connected to the output side (5) respectively. 26. An amplifier circuit comprising a fifteenth transistor (202), a sixteenth transistor (203), a seventeenth transistor (75) and an eighteenth transistor (76), the base or When the gate is the first electrode, the emitter or source is the second electrode, and the collector or drain is the third electrode, the first electrode of the fifteenth transistor (202) is connected to the input side (2). At the same time, a sixteenth transistor (20) having a polarity opposite to that of the fifteenth transistor (202).
3) the first electrode is connected, and the second electrode of the fifteenth transistor (202) is connected to the first electrode of a seventeenth transistor (75) having a polarity opposite to that of the fifteenth transistor (202). Is connected to the second electrode of the 16th transistor (203),
An eighteenth electrode having a polarity opposite to that of the sixteenth transistor (203)
The first electrode of the transistor (76) of the first transistor is connected to the third electrode of the fifteenth transistor (202) of the first transistor.
The second electrode of the sixteenth transistor (203) is connected, the second electrode of the fifteenth transistor (202) is connected to the third electrode of the sixteenth transistor (203), and the seventeenth electrode of the seventeenth transistor (203) is connected. A wide band amplifier circuit (FIG. 42), characterized in that the second electrode of the transistor (75) and the second electrode of the eighteenth transistor (76) are connected to the output side (5), respectively. 27. Nineteenth transistor (16 or 3)
In the amplifier circuit including, when the base or gate of the transistor is the first electrode, the emitter or source is the second electrode, and the collector or drain is the third electrode, the first electrode or the second electrode is used. One terminal of the first coil (102) and one terminal of the capacitor (228) are connected to the third electrode of the nineteenth transistor (16 or 3), at least one of which is connected to the input side (2). Connect and
One terminal of the second coil (74) and the other terminal of the first coil (102) are connected to the output side (5), and the other terminal of the second coil (74) and the capacitor are connected. A wideband amplifier circuit (FIGS. 44 and 45) characterized by being connected to the other terminal of (228). 28. The wideband amplification circuit according to claim 16, wherein unnecessary radiation from the wideband amplification circuit is suppressed by shielding the periphery of the wideband amplification circuit with a conductor plate (LP). Circuit (Figure 46).