JP3359770B2 - Transistor high frequency power amplifier - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transistor high-frequency power amplifier, and more particularly, to a high-frequency power amplifier used in a portable communication device driven by a battery without shortening the life of the battery.
In addition, the present invention relates to a transistor high-frequency power amplifier that always outputs a transmission signal with constant power irrespective of battery voltage fluctuation.

[0002]

2. Description of the Related Art Conventionally, a portable communication device uses a transistor high-frequency power amplifier in a transmission section and is driven by a battery.

[0003] Generally, in a device using a battery as a power supply, the output voltage of the battery is higher than the rated output voltage immediately after the battery of the power supply is replaced. The voltage gradually decreases, and eventually becomes the rated output voltage, and further becomes lower than the rated output voltage, and even in a portable communication device powered by a battery,
This is no exception.

In a portable communication device, the output power of a transmission signal is determined, and the output power of the transmission signal depends on the degree of amplification of a high-frequency power amplifier of the portable communication device.
Also, the amplification of the high-frequency power amplifier depends on the output voltage of the battery, and the amplification increases when the output voltage of the battery is high, while the amplification increases when the output voltage of the battery decreases. Also decreases.

Therefore, in such a high-frequency power amplifier used in a portable communication device, a constant voltage circuit is provided between the battery and the high-frequency power amplifier in order to keep the output power of the transmission signal of the portable communication device constant at all times. This constant voltage circuit keeps the output voltage of the battery that fluctuates over time constant, and suppresses the fluctuating output power of the transmission signal of the portable communication device over time.

FIG. 3 is a circuit diagram showing an example of a configuration of a known transistor high-frequency power amplifier of a portable communication device.

As shown in FIG. 3, a transistor high-frequency power amplifier includes an amplification stage 3 for amplifying the power of a high-frequency signal.
1, a bias voltage setting stage 32, a constant voltage circuit 33,
It comprises a battery 34. In this case, the amplification stage 31
A first-stage amplification transistor 35, a second-stage amplification transistor 36, and a last-stage amplification transistor 37 are provided, and the emitters of the transistors 35, 36, and 37 are grounded. The base of the first-stage amplification transistor 35 is connected to the signal input terminal 38 via the capacitor 42 (1) and the resistor 42 (2), and the collector of the output amplification transistor 37 is connected to the capacitor 46 (1) and the resistor 46 (1). (2)
And to the output of the constant voltage circuit 33 via the resistor 46 (3). Further, the collector of the first-stage amplifying transistor 35 is connected to the base of the next-stage amplifying transistor 36 via the capacitor 43 (1) and the resistor 43 (2).
It is connected to the base of the final stage amplifying transistor 37 via (1) and to the output of the constant voltage circuit 33 via a resistor 45 (2).

The bias voltage setting stage 32 includes a first bias voltage setting transistor 40 and a second bias voltage setting transistor 41, and the collector of the first bias voltage setting transistor 40 is a resistor. 47
It is connected to the base of the second bias voltage setting transistor 41 via (1) and is grounded via the resistor 47 (2). The first bias voltage setting transistor 40 has an emitter connected to the collector of the first-stage amplification transistor 34 via the inductor 43 (3) and the resistor 43 (2), and a constant voltage via the resistor 48 (3). Connected to the output of the circuit 33 and the collector
8 (1) and 48 (2) are grounded, and are also connected to the base of the first stage amplifying transistor 35 via resistors 48 (1) and 42 (3). The base of the first bias voltage setting transistor 40 is connected to a constant voltage circuit 33 via a diode 48 (5) and a resistor 48 (4).
, And grounded via a resistor 48 (6) and a variable resistor 48 (7). The collector of the second bias voltage setting transistor 41 is a resistor 47.
(4) is connected to the output of the constant voltage circuit 33, the emitter is grounded via a resistor 47 (3), and the base of the next stage amplifying transistor 36 and a resistor 45 are connected via a resistor 43 (4). These are connected to the base of the final-stage amplification transistor 37 via (3).

The input of the constant voltage circuit 33 is a battery 34.
, And the negative electrode side of the battery 34 is grounded. In this example, the battery 34 has a rated output voltage of 3.6 V and an initial output voltage of 4.5 V. The constant voltage circuit 33 outputs a constant voltage of 2.9 V when the input voltage is 3.6 V or more.

[0010] The known transistor high-frequency power amplifier according to the above configuration operates as follows.

When the voltage of the battery 34 is constant at 2.9 V in the constant voltage circuit 33 and then supplied to the amplification stage 31 and the bias voltage setting stage 32, respectively,
A pre-stage circuit (not shown) is connected to the signal input terminal 38 of the amplification stage 31.
, The high-frequency signal is first amplified by the first-stage amplification transistor 35, and then
The signal is further amplified by the next-stage amplifying transistor 36 and finally amplified to a predetermined power by the final-stage amplifying transistor 37, and is transmitted through a signal output terminal 39 to an antenna (not shown).
And transmitted from the antenna.

In this case, in the amplifying stage 31, the collector of the next-stage amplifying transistor 36 and the collector of the final-stage amplifying transistor 37 are supplied with a constant voltage directly from the constant voltage circuit 33 as a driving voltage. The base and collector of the transistor 35, the base of the next-stage amplifying transistor 36, and the base of the final-stage amplifying transistor 37 are controlled by the constant voltage of the constant voltage circuit 33 adjusted to an appropriate voltage in the bias voltage setting stage 32 by the drive voltage or Each is supplied as a bias voltage.

[0013]

A known transistor high-frequency power amplifier used in a portable communication device powered by a battery has a constant voltage circuit 33 provided between a battery 34 and an amplification stage 31 as described above. However, when the constant voltage circuit 33 is provided, a voltage drop occurs inside the constant voltage circuit 33, and the drive voltage supplied to the amplification stage 31 is reduced by the voltage drop. As a result, There is a problem that the life of the battery 34 is shortened.

In general, a transistor high-frequency power amplifier consumes a large amount of power, so it is necessary to increase the capacity of the constant voltage circuit 33. In addition, since the current flowing through the constant voltage circuit 33 is large, , The power consumption increases. For this reason, the known transistor high-frequency power amplifier has a problem that the life of the battery 34 is shortened.

The present invention solves these problems. It is an object of the present invention to reduce the capacity and power consumption of a constant voltage circuit and to prolong the life of a battery while keeping the power of a transmission signal constant. It is another object of the present invention to provide a transistor high-frequency power amplifier.

[0016]

In order to achieve the above object, the present invention relates to a high-frequency power amplifying stage for use in a portable communication device powered by a battery and comprising one or more transistors; A constant voltage circuit that inputs a battery voltage and outputs a constant voltage, and subtracts the battery voltage from the constant voltage output from the constant voltage circuit to obtain a control voltage that fluctuates inversely with the fluctuation of the output voltage of the battery. A bias voltage setting means comprising a subtraction circuit for outputting, and a transistor high-frequency power amplifier for supplying the battery voltage as a drive voltage to an output electrode of the transistor and supplying the control voltage as a bias voltage to an input electrode of the transistor. The subtraction circuit has an emitter connected to the output of the constant voltage circuit, and a base connected to the constant voltage circuit via a series connection of a first resistor and a diode. An output, a first resistor connected to the battery via a second resistor, and a ground via a third resistor, and a collector connected to the ground via a fourth resistor. A transistor for generating the control voltage based on a voltage obtained at the collector;

[0017]

In the above means, a battery voltage is inputted, and a bias voltage setting stage for outputting a control voltage that fluctuates in reverse to the fluctuation of the battery voltage is provided, and the battery voltage is driven to the output electrode of the transistor in the transistor high-frequency power amplification stage. When the battery voltage is high, such as when the battery has just been replaced, the control voltage obtained at the bias voltage setting stage is supplied to the control electrode of the transistor as the bias voltage. Is controlled so that a low bias voltage is supplied to the control electrode of the transistor so that the current flowing through the transistor becomes relatively small, while the battery voltage is reduced, as when a considerable amount of time has passed since the battery was replaced. When the voltage drops, a high bias voltage is supplied to the control electrode of the transistor, and the current flowing through the transistor decreases. Since is controlled to comparatively large, the signal amplification factor of the transistor RF power amplifier stage is not affected by the magnitude of the battery voltage, the output level of the transmission signal is controlled to be constant at all times. In addition, since a constant voltage circuit is incorporated in the bias voltage setting stage and the output of the constant voltage circuit is exclusively used for supplying a bias voltage to the control electrode of the transistor, the constant voltage circuit has a small capacity and a small current. Things are enough.

[0018]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a circuit diagram showing the configuration of one embodiment of a transistor high-frequency power amplifier according to the present invention.

As shown in FIG. 1, the transistor high-frequency power amplifier comprises an amplification stage 1 for amplifying the power of a high-frequency signal.
And a bias voltage setting stage 2, a battery 3, and an additionally connected transistor high frequency power amplifier on / off stage 4. In this case, the amplification stage 1 includes a first-stage amplification transistor 5, a second-stage amplification transistor 6, and a last-stage amplification transistor 7, and each of the transistors 5, 6,
The emitter of 7 is grounded. The base of the first-stage amplifying transistor 5 includes a capacitor 8 (1) and a resistor 8
(2) is connected to the signal input terminal 9, and the collector of the final stage amplifying transistor 7 is connected to the signal output terminal 11 via the capacitor 10 (1) and the resistor 10 (2). It is connected to the output of the battery 3 via (3). Further, the collector of the first-stage amplification transistor 5 is connected to the base of the next-stage amplification transistor 6 via the capacitor 12 (1) and the inductor 12 (2).
The capacitor 13 (1) is connected to the base of the transistor 37 for amplifying the final stage.
It is connected to the positive electrode side of the battery 3 via (2).

The bias voltage setting stage 2 includes a first bias voltage setting transistor 14, a second bias voltage setting transistor 15, and a constant voltage circuit 16, and the first bias voltage setting transistor The collector of the transistor 14 is connected to the base of the second bias voltage setting transistor 15 via the resistor 17 (1).
It is grounded via a variable resistor 17 (2). The first bias voltage setting transistor 14 has an emitter connected to the collector of the first-stage amplification transistor 5 via the inductor 12 (3) and the inductor 12 (2), and a constant voltage via the resistor 18 (3). The collector is connected to the output of the circuit 16, the collector is grounded through the resistors 18 (1) and 18 (2), and is connected to the base of the transistor 5 for amplifying the first stage through the resistor 18 (4) and the inductor 8 (3). It is connected. The base of the first bias voltage setting transistor 14 includes a diode 20 (2) and a resistor 20
Connected to the output of the constant voltage circuit 16 via (1), connected to the on / off stage 4 of the transistor high-frequency power amplifier via the resistor 20 (3), and connected to the positive electrode side of the battery 3 via the resistor 19 Have been. The second bias voltage setting transistor 15 has a collector connected to the positive electrode side of the battery 3 via a resistor 17 (4), and an emitter connected to the resistor 17 (4).
(3) grounded through the inductor 12
(4) via the base of the next stage amplifying transistor 6;
They are connected to the bases of the final-stage amplification transistors 7 via the inductors 13 (3). Constant voltage circuit 16
Has an input connected to the positive electrode side of the battery 3.

Further, the on / off stage 4 of the transistor high-frequency power amplifier includes a common-emitter switching transistor 21. The switching transistor 21 has a base connected to a switching signal input terminal 23 via a resistor 22, and a collector connected to a resistor 20 (7). ) Is connected to the base of the first bias voltage setting transistor 16. Note that, also in the present embodiment, the battery 3 has a rated output voltage of 3.6 V and an initial output voltage of 4.5 V. The constant voltage circuit 18 outputs a constant voltage of 2.9 V when the input voltage is 3.6 V or more.

The transistor high-frequency power amplifier according to this embodiment having the above-described structure operates as follows.

Now, when the voltage of the battery 3 is supplied to the amplification stage 1 directly and via the bias voltage setting stage 2 and a positive signal is supplied to the switching signal input terminal 23 of the on / off stage 4, the switching transistor 21 turns on to activate the bias voltage setting stage 2, which supplies a predetermined bias voltage to the amplification stage 1, as described in detail below. For this reason, when a high-frequency signal is applied to the signal input terminal 9 of the amplification stage 1 from a previous-stage circuit (not shown), the high-frequency signal is first amplified by the first-stage amplification transistor 5, and then, similarly, by the next-stage amplification transistor The signal is further amplified at 6 and finally amplified to a required power by the final-stage amplifying transistor 7, supplied to an antenna (not shown) via the signal output terminal 10, and transmitted from the antenna.

On the other hand, when a negative polarity signal or a reference potential signal is supplied to the switching signal input terminal 23, the switching transistor 21 is turned off, and the bias voltage setting stage 2 is changed to an inactive state, and the bias to the amplification stage 1 is changed. Stop supplying voltage. Therefore, even if a high-frequency signal is applied to the signal input terminal 9 of the amplification stage 1 from a preceding circuit (not shown), the high-frequency signal is not amplified by the amplification stage 1 and is not transmitted from the antenna. .

FIG. 2 is a characteristic diagram showing the relationship between the voltage of the battery 3 and the output power of the transmission signal when the resistance value of the resistor 19 is used as a parameter.

In FIG. 2, the vertical axis represents the output power of the transmission signal, and the horizontal axis represents the voltage of the battery 3.

Here, the operation of the bias voltage setting stage 2 in the embodiment shown in FIG. 1 will be described with reference to FIG. In this operation, however, it is assumed that a positive polarity signal is supplied to the switching signal input terminal 23 and the bias voltage setting stage 2 is in an active state.

When the battery voltage V _{B of the} battery 3 is supplied to the bias voltage setting stage 2, the battery voltage V _B is applied to the constant voltage circuit 1.
6 and a constant voltage V _{2.9 of 2.9} V is obtained at the output of the constant voltage circuit 16. A constant voltage V _2.9 is applied to the first bias voltage setting transistor 14 via the resistor 18 (3) at the emitter, and the resistor 20 (1) is connected to the base.
The constant voltage V _2.9 divided by the diode 20 (2) and the resistor 20 (3) and the battery voltage V _B via the resistor 19 are applied. In this case, the first bias voltage setting transistor 14, while the emitter voltage is maintained substantially constant voltage depending on the constant voltage V _2.9, a substantially constant voltage the base voltage is also dependent on the constant voltage V _2.9 since the superposed voltage V _SUM of the variable voltage which depends on the battery voltage V _B, to generate the collector voltage V _C16 vary depending on the battery voltage V _B to the collector voltage. The fluctuating collector voltage V _C16 is supplied to the base of the second bias voltage setting transistor 15 via the resistor 17 (1), and the battery voltage V _B is also supplied to the emitter of the second bias voltage setting transistor 15. Generates a fluctuating emitter voltage V _E17 depending on the voltage. And the fluctuating collector voltage V
_C16 is a resistor 18 (1), 18 (4), an inductor 8
The fluctuating emitter voltage V _{E17, which} is supplied to the base of the first-stage amplification transistor 5 via (3), is supplied to the base of the next-stage amplification transistor 6 via the inductor 12 (4). The signal is supplied to the base of the final-stage amplification transistor 7 via (3).

[0030] In this embodiment, when the battery voltage V _B indicates the 3.6V is the rated output voltage of the battery 3, as the superposed voltage V _SUM becomes a predetermined voltage, e.g. 2V, resistance 2
0 (5) and the resistance value of the resistor 20 (7) are determined, and the collector voltage of the first bias voltage setting transistor 14 obtained at that time (this is referred to as a standard collector voltage V _C16S ).
Thus, the resistors 18 (1) and 18 (1) and 18 (1) are set so that the base bias voltage of the first-stage amplification transistor 5 becomes the predetermined voltage _VB5.
The respective resistance values of (2) are set, and the base bias of the next stage amplifying transistor 6 is determined by the emitter voltage of the second bias voltage setting transistor 15 (this is referred to as a standard emitter voltage _VE17S ). The respective resistance values of the resistor 17 (1), the variable resistor 17 (2), and the resistor 17 (3) are set so that the voltage becomes the predetermined voltage V _B6 and the base bias voltage of the final stage amplifying transistor 7 becomes the predetermined voltage V _B7. Set.

When such a resistance value is set, the battery 3
Shortly after replacing the battery, the voltage V of the battery 3
_{When B} is equal to or higher than 3.6 V, the superimposed voltage V _SUM is higher than a predetermined voltage, for example, 2 V, and the collector current of the first bias voltage setting transistor 14 is small.
The collector voltage V _C16 of the bias voltage setting transistor 14 is lower than the standard collector voltage V _C16S , and at the same time, the emitter voltage V _{E17 of} the second bias voltage setting transistor 15 is also lower than the standard emitter voltage V _E17S . For this reason, the base bias voltage of the first-stage amplification transistor 5 becomes lower than the predetermined voltage V _B5 , and the base bias voltage of the next-stage amplification transistor 6 and the base bias voltage of the output amplification transistor 7 are each equal to the predetermined voltage V _{B5. B6} and lower than the predetermined voltage _VB7 .

As described above, the voltage V _{B of the} battery 3 is applied via the bias voltage setting stage 2 to the bases of the first, second, and last amplification transistors 5, 6, and 7 constituting the amplification stage 1.
There corresponds to the value exceeding the rated output voltage, since the base bias voltage of a magnitude that decreases in inverse proportion to the value is supplied, amplified voltage V _B of the battery 3 due to higher than rated output voltage The increase in the amplification of the stage 1 is offset by the decrease in the base bias voltage supplied to the bases of the first, second, and last amplification transistors 5, 6, and 7, and the transmission signal obtained by the amplification stage 1 the output power is constant irrespective of the excess voltage V _B of the battery 3.

By the way, when the voltage V _{B of the} battery 3 is slightly lower than 3.6 V, the superimposed voltage V _SUM becomes a predetermined voltage,
For example, the voltage drops below 2 V. At this time, the constant voltage V _2.9 output from the constant voltage circuit 16 also slightly decreases, the collector current of the first bias voltage setting transistor 14 slightly increases, and the first bias voltage Voltage setting transistor 1
4, the collector voltage V _C16 slightly increases from the standard collector voltage V _C16S , and at the same time, the emitter voltage V _{E17 of} the second bias voltage setting transistor 15 also slightly increases from the standard emitter voltage V _E17S . Therefore, the base bias voltage of the first-stage amplification transistor 5 is slightly higher than the predetermined voltage V _B5 , and the base bias voltage of the next-stage amplification transistor 6 and the base bias voltage of the last-stage amplification transistor 7 are respectively Since the voltage slightly increases from the predetermined voltage V _B6 and the predetermined voltage V _B7 , the voltage V _B
Is reduced from the standard output voltage, the decrease in the amplification of the amplification stage 1 is canceled out, and the fluctuation of the amplification is slightly compensated.

In this embodiment, the resistance value of the resistor 19 is
When the voltage is changed to 7.5 k ohms, 12 k ohms, 15 k ohms, or infinity (not connected), the degree of the voltage fluctuation of the superimposed voltage V _SUM accompanying the fluctuation of the voltage V _B of the battery 3, that is, the amplification stage 1
The output power of the transmission signal changes as shown in FIG.
In this case, even if the voltage V _{B of the} battery 3 fluctuates, it is desirable that the change in the output power of the transmission signal of the amplification stage 1 be small. Is small, for example, 12k
You have chosen to be an ohm.

In the present embodiment, the resistor 18 (3) connected to the emitter of the first bias voltage setting transistor 14 is connected to the first stage when a large amplitude signal is input to the signal input terminal 9. This is to prevent the first stage amplifying transistor 5 and the constant voltage circuit 16 from being destroyed by a large current flowing through the collector of the amplifying transistor 5. When the collector current of the first-stage amplification transistor 5 increases, both the emitter voltage and the collector voltage of the first bias voltage setting transistor 14 decrease due to the resistor 18 (3). 5 is decreased. That is, the first bias voltage setting transistor 14
The bias circuit of the first-stage amplification transistor 5 includes a feedback bias circuit, and has a function of stabilizing the DC bias of the first-stage amplification transistor 5.

As described above, according to the present embodiment, when the voltage of the battery 3 is higher than the rated output voltage, the base bias voltage of each of the transistors 5, 6, 7 constituting the amplification stage 1 is changed to the standard base bias. Since the voltage is lower than the voltage and the increase in the amplification of the amplification stage 1 due to the high voltage of the battery 3 is suppressed, the amplification stage 1
The output power of the transmission signal from the battery 3 can be kept constant, and at the same time, excessive consumption of the battery 3 due to the high voltage of the battery 3 is suppressed, and the life of the battery 3 is prolonged.

Also, according to the present embodiment, the constant voltage circuit 16
Is provided in the bias voltage setting stage 2 and is used to apply a constant voltage only to a point where a relatively small current such as a base bias voltage of each of the amplifying transistors 5, 6, 7 is supplied. It is sufficient to use a device having a small capacity and outputting a relatively small current. The power consumption in the constant voltage circuit 16 is small, and accordingly, the consumption of the battery 3 is suppressed and the life of the battery 3 is further prolonged.

In this embodiment, the amplification stage 1 has three stages.
Although the description has been given by taking as an example the case where the amplifier stage is composed of two amplifying transistors 5, 6, and 7, the amplifying stage 1 of the present invention is used.
Is not necessarily composed of three amplifying transistors 5, 6,.
The structure is not limited to the structure using the transistor 7, and any structure having at least one transistor may be used.

The voltage V _B of the battery 3 when the base bias voltage of each of the transistors 5, 6, and 7 constituting the amplification stage 1 is lower than the standard base bias voltage is a standard output voltage. The voltage is not necessarily limited to 6 V, and may be set to a value equal to or higher than the standard output voltage or equal to or lower than the standard output voltage.

[0040]

As described in detail above, according to the present invention, when the battery voltage is higher than the required voltage, such as when the battery has just been replaced, the high-frequency power amplifier stage is formed. A low bias voltage is supplied to the input electrode of each transistor, so that the current flowing through the transistor is controlled to be relatively small, while the voltage of the battery is reduced as if a considerable amount of time had passed since the battery was replaced. When the voltage drops, a high bias voltage is supplied to the input electrode of the transistor, and the current flowing through the transistor is controlled to be relatively large, so the amplification of the high-frequency power amplification stage affects the magnitude of the battery voltage. Instead, it is controlled so that the output power of the transmission signal is always constant.

In addition, according to the present invention, even when the battery voltage is high, excessive power is not supplied to the high-frequency power amplification stage, and the battery life is prolonged accordingly. There is an effect that it becomes possible.

Further, according to the present invention, since the constant voltage circuit needs to have a small capacity and a small current, the power consumption in the constant voltage circuit is small, and the life of the battery is prolonged accordingly. There is an effect that it becomes possible to do.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a configuration of an embodiment of a transistor high-frequency power amplifier according to the present invention.

FIG. 2 is a characteristic diagram illustrating a relationship between a battery voltage and an output power of a transmission signal when a resistance value of a resistor 19 is used as a parameter.

FIG. 3 is a circuit diagram showing a configuration of an example of a known transistor high-frequency power amplifier.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Amplification stage 2 Bias voltage setting stage 3 Battery 4 On / off stage of transistor high frequency power amplifier 5 First stage transistor 6 Secondary stage transistor 7 Final stage transistor 8 (1), 10 (1), 12 (1), 13 (1) Capacitor 8 (2), 10 (2), 17 (1), 17 (3), 17
(4), 18 (1) to 18 (4), 19, 20 (1),
20 (3), 22 Resistance 8 (3), 10 (3), 12 (2) to 12 (4), 13
(2), 13 (3) Inductor 9 Signal input terminal 11 Signal output terminal 14 First bias voltage setting transistor 15 Second bias voltage setting transistor 16 Constant voltage circuit 17 (2) Variable resistor 20 (2) Diode

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H03F 1/30 H03G 3/10 H04B 1/04

Claims (3)

(57) [Claims] 1. A high-frequency power amplification stage used in a portable communication device that uses a battery as a power supply, the high-frequency power amplification stage including one or more transistors, a constant voltage circuit that inputs the battery voltage and outputs a constant voltage, and Bias voltage setting means comprising a subtraction circuit for subtracting a constant voltage output from the constant voltage circuit and the battery voltage and outputting a control voltage that fluctuates in reverse to the fluctuation of the output voltage of the battery; and an output of the transistor. A transistor high-frequency power amplifier that supplies the battery voltage as a driving voltage to an electrode and supplies the control voltage as a bias voltage to an input electrode of the transistor, wherein the subtraction circuit has an emitter connected to an output of the constant voltage circuit. The base has an output of the constant voltage circuit via a series connection of a first resistor and a diode, the battery via a second resistor, and a third resistor. A first transistor connected to the ground via a resistor and having a collector connected to the ground via a fourth resistor for generating the control voltage based on a voltage available at the collector A high frequency power transistor transistor. 2. The high-frequency power amplifier stage includes a first-stage transistor amplifier having a collector connected to an emitter of the first transistor and a base connected to a collector of the first transistor. 2. The transistor high-frequency power amplifier according to 1. 3. The transistor high-frequency power amplifier according to claim 2, wherein a fifth resistor having a small resistance value is connected between an emitter of said first transistor and an output of said constant voltage circuit. .