JP2003188664A - High frequency power amplifier - Google Patents

Abstract

(57) [Summary] [PROBLEMS] As demands for higher performance and wider bandwidth are increasing, these higher performances are required without adding new circuits.
Provided is a high-frequency power amplifier capable of coping with a wider band. SOLUTION: The output matching circuit 13 includes a high-frequency transistor Q11, an input matching circuit 12, an output matching circuit 13, and a drain microstrip line L12.
The high-frequency power amplifier 11 includes a distributed constant line L13 divided on the way and a resistor R15 connecting the divided distributed constant line L13. A parallel circuit 18 is formed by a distributed constant line L13 divided on the way and a resistor R15 connecting the line, and a high frequency band propagates through the capacitor component C15 as it is, and a low frequency band is output via the resistor R15. Terminal
The matching with the load resistor connected to the circuit 17 can be achieved in both the high and low frequency ranges, and further higher performance and wider bandwidth can be realized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used in mobile communication devices such as mobile phones for amplifying high frequency power such as microwave band and used for amplifying signals in high frequency and wide band. The present invention relates to a high frequency power amplifier.

[0002]

2. Description of the Related Art In recent years, there has been an increasing demand for miniaturization and weight reduction of semiconductor devices and electronic parts used in mobile communication devices such as mobile phones, and in particular, in these devices, microwave bands, etc. The demands for higher efficiency, smaller size, higher performance, and cost reduction for the high-frequency power amplifier that amplifies in order to transmit the high-frequency signal are increasing.

FIG. 9 is a circuit diagram showing an example of a circuit configuration of a conventional high frequency amplifier. In FIG. 9, the high frequency amplifier 1 is constructed on a dielectric substrate (not shown) having a relative dielectric constant of a predetermined value. Q1 is a high frequency transistor as an amplifying section for amplifying a high frequency signal, and is connected to the electrode section of the dielectric substrate by wire bonding. Here, an example using a field effect transistor (FET) is shown. 2 is an input matching circuit, which is a high frequency transistor Q1
It is for impedance matching with respect to the fundamental frequency of the high frequency signal, which is connected to the gate electrode which is the input electrode of. Reference numeral 3 denotes an output matching circuit connected to the drain electrode which is the output electrode of the high frequency transistor Q1.

The input matching circuit 2 uses a distributed constant line, for example, an input side microstrip line L1 for optimizing impedance matching with an input circuit (not shown) connected to the input terminal 4. An input side DC blocking capacitor C1 is connected between the gate electrode of the high frequency transistor Q1 and the input terminal 4. A gate bias voltage supply terminal 5 is connected to the input side microstrip line L1 via a resistor R1 and is grounded via an input matching capacitor C2.

On the other hand, the output matching circuit 3 is a distributed constant line for matching the desired output characteristics by optimizing impedance matching with an external circuit (not shown) connected to the output terminal 7, for example, a distributed constant line. An output side microstrip line L3 is used, and an output side DC blocking capacitor C is provided between the drain electrode of the high frequency transistor Q1 and the output terminal 7.
3 is connected.

An output matching capacitor C4 and a microstrip line L4 are connected to the output terminal 7,
It is grounded through this.

Further, the drain electrode of the high frequency transistor Q1 is provided with a drain bias supply terminal 6 as a bias circuit for supplying a direct current thereto via a drain microstrip line L2 which is a distributed constant line.
It is connected in a form such as being connected to the output side microstrip line L3. The drain microstrip line L2 is normally a quarter of the fundamental frequency.
The length of the wavelength is set so that the impedance looks infinite when viewed from the drain side of the high-frequency transistor Q1, or the line length is set to a large impedance that can be ignored when viewed from the impedance of the circuit. There is.

In the conventional high frequency power amplifier 1,
With such a configuration, the output impedance is matched to the fundamental frequency of the high frequency signal to achieve high performance.

[0009]

However, as the demand for higher performance and wider bandwidth increases, it is necessary to strengthen the matching with the load resistance connected to the output terminal in both high and low frequencies. , There is a demand for higher performance and wider bandwidth.

The present invention has been devised in view of the above circumstances, and an object thereof is to achieve higher performance by matching the load resistance connected to the output terminal in both the high and low frequency bands. An object of the present invention is to provide a high-frequency power amplifier that can meet the demand for higher bandwidth and wider bandwidth.

[0011]

A first high-frequency power amplifier according to the present invention is connected to the input electrode and a high-frequency amplifier for amplifying a high-frequency signal from an input electrode and sending it from the output electrode. The output matching circuit includes an input matching circuit for impedance matching with respect to a fundamental frequency of a signal, an output matching circuit connected to the output electrode, and a direct current bias circuit connected to the output electrode, and the output matching circuit. The circuit is characterized in that it is composed of a distributed constant line divided on the way and a resistor connecting the divided distributed constant lines.

According to the first high frequency power amplifier of the present invention as described above, the output matching circuit divides the distributed constant line which is a transmission line on the way and connects the divided distributed constant lines with a resistor. Therefore, the parallel circuit is composed of the capacitor component and the resistance generated between the divided distributed constant line gaps, and the high frequency component propagates through the capacitor part as it is, and The frequency component of the frequency range can be matched to the load resistance connected to the output terminal through the resistance part in both the high and low frequency bands, which further improves the high-performance amplifier.
A wide band can be realized.

The second high frequency power amplifier of the present invention is connected to the high frequency amplifier for amplifying the high frequency signal from the input electrode and transmitting it from the output electrode, and has a fundamental frequency of the high frequency signal. An input matching circuit for impedance matching with respect to the output electrode, an output matching circuit connected to the output electrode, and a DC current bias circuit connected to the output electrode. It is characterized in that it is composed of a distributed constant line divided by and a resistor and a capacitor connecting these divided distributed constant lines.

According to the second high frequency power amplifier of the present invention as described above, the output matching circuit divides the distributed constant line which is a transmission line midway, and a resistor and a capacitor are provided between the divided distributed constant lines. Since they are connected and connected, a parallel circuit is composed of these capacitors and resistors.High frequency components propagate through the capacitors as they are, and low frequency components pass through the resistors to the output terminal. It is possible to match the load resistance connected to the high frequency range and the low range of the frequency, and by doing so, it is possible to further improve the performance and broaden the band of the high frequency amplifier.

The third high frequency power amplifier of the present invention is connected to the high frequency amplifier for amplifying the high frequency signal from the input electrode and transmitting it from the output electrode, and has a fundamental frequency of the high frequency signal. An input matching circuit for impedance matching with respect to the output electrode, an output matching circuit connected to the output electrode, and a DC current bias circuit connected to the output electrode. It is characterized in that it is composed of a distributed constant line divided by and a resistor and a wire connecting these distributed constant lines.

According to the third high frequency power amplifier of the present invention as described above, the output matching circuit divides the distributed constant line which is a transmission line midway, and a resistor and a wire are provided between the divided distributed constant lines. Since they are connected and connected, a parallel circuit is formed by the inductor component of the wire itself and the resistor, and the high frequency component has a high impedance in the inductor component, so the inductor component of the wire itself The combined impedance of the parallel circuit composed of the resistor and the resistor has almost the same resistance value, and matching can be achieved by using a resistor having the same resistance value as the load resistor connected to the output terminal. In addition, the low frequency component has low impedance in the inductor component,
Since it propagates as it is, it is possible to match the load resistance connected to the output terminal with both high and low frequency bands, which further improves the high-performance amplifier.
A wide band can be realized.

The fourth high frequency power amplifier of the present invention is connected to the high frequency amplifier for amplifying the high frequency signal from the input electrode and transmitting it from the output electrode, and has a fundamental frequency of the high frequency signal. An input matching circuit for impedance matching with respect to the output electrode, an output matching circuit connected to the output electrode, and a DC current bias circuit connected to the output electrode. It is characterized in that it is composed of a distributed constant line divided by and a resistor and an inductor connecting these divided distributed constant lines.

According to the fourth high frequency power amplifier of the present invention as described above, the output matching circuit divides the distributed constant line which is a transmission line on the way, and a resistor and an inductor are provided between the divided distributed constant lines. Since the inductors and the resistors are connected to each other, a parallel circuit is configured, and a high frequency component has a high impedance in the inductor. Therefore, a parallel circuit of the inductor and the resistors is connected. The combined impedance has almost a resistance value, and matching can be achieved by using a resistance having the same resistance value as the load resistance connected to the output terminal. Also,
Since the low frequency component has low impedance in the inductor, it propagates as it is, and it is possible to match the load resistance connected to the output terminal with both the high and low frequency bands. It is possible to realize higher performance and wider band of the amplifier.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A high frequency power amplifier according to the present invention will be described below with reference to the drawings.

FIG. 1 is a circuit diagram showing a circuit configuration of an example of an embodiment of a first high frequency power amplifier of the present invention.

In FIG. 1, the first high frequency power amplifier 11 of the present invention is constructed on a dielectric substrate (not shown) made of a dielectric material having a relative dielectric constant of a predetermined value.
Q11 is a high-frequency transistor as a high-frequency amplifier that amplifies signals, and is an amplifier used in a frequency range to which a distributed constant line such as several hundred MHz to several GHz can be applied. Here, an example using a field effect transistor (FET) is shown.

Reference numeral 12 denotes an input matching circuit, which is connected to a gate electrode which is an input electrode of the high frequency transistor Q11, for impedance matching with respect to the fundamental frequency of the high frequency signal. 13 is a high frequency transistor Q
The output matching circuit is connected to the drain electrode which is the output electrode of 11.

The input matching circuit 12 uses a distributed constant line for optimizing impedance matching with an input circuit (not shown) connected to the input terminal 14, for example, an input side microstrip line L11. There is. Further, the input side microstrip line L11 is connected to the gate bias voltage supply terminal 15 via the resistor R11 and is grounded via the input matching capacitor C12.

On the other hand, the output matching circuit 13 has desired output characteristics such as distortion characteristics, output power, current consumption, etc. by optimizing impedance matching with an external circuit (not shown) connected to the output terminal 17. The distributed constant line, for example, the output side microstrip line L13, is used for matching so as to satisfy the above conditions singly or simultaneously. An output DC blocking capacitor C13 is connected between the drain electrode of the high frequency transistor Q11 and the output terminal 17.

An output matching capacitor C14 and a microstrip line L14 are connected to the output terminal 17, and are grounded via this. The output side microstrip line L13, the output matching capacitor C14, and the microstrip line L14 form an output matching circuit 13.

Further, the drain electrode of the high frequency transistor Q11 has a drain bias supply terminal 16 as a bias circuit for supplying a direct current thereto via a drain microstrip line L12 which is a distributed constant line.
It is connected in such a form as to be connected to the output side microstrip line L13.

In the first high frequency power amplifier 11 of the present invention, the output side microstrip line L13 is divided into two in the middle, and the divided gaps are connected by the resistor R15. It is characterized by being

In FIG. 1, C15 is a capacitor component generated in the gap between the divided output side microstrip lines L13, and R15 is a resistor connecting the divided output side microstrip lines L13. In this way, the output side microstrip line L13 which is the distributed constant line forming the output matching circuit 13 is divided in the middle, and the resistor R15 is provided between the divided output side microstrip lines L13.
The parallel circuit 18 is constituted by the capacitor component C15 and the resistor R15 because of the connection by the capacitor component C15 and the capacitor component C15 in the high frequency signal, that is, in the high frequency range.
Has a low impedance value, and as a result, the combined impedance of the parallel circuit 18 including the resistor R15 and the capacitor component C15 is low, and the microstrip line L
The output matching circuit 13 including 13 and L14 and the capacitor C14 enables matching with a load resistor (not shown) connected to the output terminal 17.

On the other hand, at low frequencies, the impedance of the capacitor component C15 becomes high, and the combined impedance of the parallel circuit 18 composed of the resistor R15 and the capacitor component C15 approaches the resistance value of the resistor R15 infinitely. . Therefore, by matching the resistance value of the resistor R15 with the resistance value of the load resistor connected to the output terminal 17, matching can be achieved even in the low frequency range. As a result, higher performance and wider bandwidth can be realized.

An example of the parallel circuit 18 in the first high frequency power amplifier 11 of the present invention will be described with reference to the side view shown in FIG.

In FIG. 2, for example, the capacitor component C15
Describe how to determine the value of. The distance S between the gaps of the output-side microstrip line L13 divided on the way is 1 mm, the thickness of the dielectric substrate on which the first high-frequency power amplifier 11 is formed is 1.6 mm, and the dielectric constant of the dielectric substrate is 9 mm. , The line width of the output side microstrip line L13 is W, the distance to the ground is H, and the gap capacitance C15 when the ratio W / H is set to 10 is C = W × (S / W) ^m × exp ( When calculated by the theoretical formula of k) and simulation, it is about 0.5.
It becomes pF. Note that m is W / H x (0.619 log W / H
-0.3853), and k is 4.26 to 1.453 log (W / H). When the load resistance connected to the output terminal 17 is 50Ω, the resistance R15 is set to 50Ω.

With the parallel circuit 18 constructed in this manner, for high frequency frequencies, the output terminals are provided by the microstrip lines L13, L14 and the capacitor C14.
Match the load resistance of 50Ω connected to 17. Further, in the low frequency range, the impedance of the capacitor component C15 becomes high, so that the combined impedance of the parallel circuit 18 approaches the resistance value of the resistor R15, that is, 50Ω in this example, and is connected to the output terminal 17. It is possible to match the resistance value of the load resistance of 50Ω.

As a result, both the high frequency band and the low frequency band can be matched with the load resistance connected to the output terminal 17,
It is possible to meet the demand for higher performance and wider bandwidth of high frequency power amplifiers.

Next, FIG. 3 is a circuit diagram showing a circuit configuration of an example of an embodiment of a second high frequency power amplifier of the present invention.

In FIG. 3, the same parts as those in FIG. 1 are designated by the same reference numerals, and the duplicated description will be omitted. In the second high frequency power amplifier 21 of the present invention, the output side microstrip line L13 is divided into two in the middle, and the divided gaps are connected by the resistor R25 and the capacitor C25. Is characterized by.

In FIG. 3, C15 is a capacitor component generated in the gap of the divided output side microstrip line L13, R25 is a resistor for connecting the divided output side microstrip lines L13, and C25 is the same. 3 shows a capacitor connecting between the output microstrip lines L13. In this way, the output side microstrip line L13 which is the distributed constant line forming the output matching circuit 13 is divided in the middle, and the resistor R25 and the capacitor C25 are provided between the divided output side microstrip lines L13.
These capacitors C25 and resistor R25
The parallel circuit 18 is constituted by and the impedance value of the capacitor C25 becomes low in a high frequency signal, that is, in the high frequency range. As a result, the combined impedance of the parallel circuit 18 made up of the resistor R25 and the capacitor C25 is low. Becomes, microstrip line L13 and L
The output matching circuit 13 including the capacitor 14 and the capacitor C14 can match with the load resistance (not shown) connected to the output terminal 17.

On the other hand, at the frequency on the low frequency side, the impedance of the capacitor C25 becomes high, and the combined impedance of the parallel circuit 18 composed of the resistor R25 and the capacitor C25 approaches the resistance value of the resistor R25 infinitely. Therefore, by matching the resistance value of the resistor R25 with the resistance value of the load resistor connected to the output terminal 17, matching can be achieved even in the low frequency range. As a result, higher performance and wider bandwidth can be realized.

An example of the parallel circuit 28 in the second high frequency power amplifier 21 of the present invention will be described with reference to the side view shown in FIG.

In FIG. 4, the capacitor C25 is selected to be a constant whose impedance is sufficiently low with respect to the fundamental frequency. For example, if a 1000 pF ceramic capacitor is used, the impedance becomes minimum at about 50 MHz. Also, the load resistance connected to the output terminal 17 is 50
If it is Ω, the resistance R25 is set to a resistance of 50Ω.

With the parallel circuit 28 thus constructed, for high frequency frequencies, the output terminals are provided by the microstrip lines L13 and L14 and the capacitor C14.
Match the load resistance of 50Ω connected to 17. Further, in the low frequency range, the impedance of the capacitor C25 increases, so that the combined impedance of the parallel circuit 28 approaches the resistance value of the resistor R25, that is, 50Ω in this example, and is connected to the output terminal 17. It is possible to match the resistance value of the load resistance of 50Ω.

As a result, both the high and low frequencies can be matched with the load resistance connected to the output terminal 17,
It is possible to meet the demand for higher performance and wider bandwidth of high frequency power amplifiers.

Next, FIG. 5 is a circuit diagram showing a circuit configuration of an example of an embodiment of a third high-frequency power amplifier of the present invention.

In FIG. 5, the same parts as those in FIG. 1 are designated by the same reference numerals, and the duplicated description will be omitted. In the third high frequency power amplifier 31 of the present invention, the output side microstrip line L13 is divided into two in the middle, and the divided gaps are connected by the resistor R35 and the wire W35. Is characterized by.

In FIG. 5, C15 is a capacitor component generated between the gaps of the divided output side microstrip lines L13, R35 is a resistance for connecting the divided output side microstrip lines L13, and W35 is also divided. The wire connecting between the output microstrip lines L13 is shown. In this way, the output side microstrip line L13 which is the distributed constant line forming the output matching circuit 13 is divided in the middle, and the divided output side microstrip line L13 is connected by the resistor R35 and the wire W35. The inductor component of the wire W35 and the resistor R35 form a parallel circuit 38, which increases the impedance value of the inductor component of the wire W35 in a high frequency signal, that is, in a high frequency range, and as a result, the resistor R25 and the wire W35. The combined impedance of the parallel circuit 38 including the inductor component approaches the value of the resistor R35 without limit. Therefore, by matching the resistance value of the resistor R35 with the resistance value of the load resistor connected to the output terminal 17, matching with the load resistor (not shown) connected to the output terminal 17 can be achieved.

On the other hand, at the low frequency side, the impedance value of the inductor component due to the wire W35 becomes low, and as a result, the combined impedance of the parallel circuit 38 constituted by the resistor R25 and the inductor component due to the wire W35 is low. Nara, microstrip lines L13 and L14
By the output matching circuit 13 including the capacitor C14 and the capacitor C14, matching can be achieved even in the low frequency range.
As a result, higher performance and wider bandwidth can be realized.

An example of the parallel circuit 38 in the third high frequency power amplifier 31 of the present invention will be described with reference to the side view shown in FIG.

In FIG. 6, how to determine the value of the inductor component of the wire W35 will be described. The inductor component of the wire W35 is determined by the distance from GND (ground). The velocity V of the electromagnetic wave propagating through the wire (conductor wire) W35 is constant and can be represented by V = 1 / √ (ε × u). Here, ε is the dielectric constant of the substrate, which is about 9 when it is made of alumina ceramics, for example. U represents the magnetic permeability, and at this time V
Is about 1 × 10 ⁻⁸ m / s. Also, wire W35 to GN
When installed so that the distance to D is 1 mm, the inductor component of the wire W35 is about 0.6 nH due to the velocity V = 1 / √ (L × C) of the electromagnetic wave propagating through the conductor wire. Here, C is a parasitic capacitance generated between the wire W35 and GND, which is about 0.15 pF at a distance of 1 mm.
When the load resistance connected to the output terminal 17 is 50Ω, the resistance R35 is set to 50Ω.

With the parallel circuit 38 thus constructed, for the low frequency, the output terminals are provided by the microstrip lines L13 and L14 and the capacitor C14.
Match the load resistance of 50Ω connected to 17. In addition, the impedance of the inductor component of the wire W35 becomes higher in the high frequency range, which results in a parallel circuit.
The combined impedance of 38 is limitlessly the resistance value of resistor R35,
That is, in this example, the resistance value approaches 50Ω and can be matched with the resistance value of 50Ω of the load resistance connected to the output terminal 17.

As a result, both the high and low frequencies can be matched with the load resistance connected to the output terminal 17,
It is possible to meet the demand for higher performance and wider bandwidth of high frequency power amplifiers.

Next, FIG. 7 is a circuit diagram showing a circuit configuration of an example of an embodiment of a fourth high frequency power amplifier of the present invention.

In FIG. 7, the same parts as those in FIG. 1 are designated by the same reference numerals, and the duplicated description will be omitted. In the fourth high frequency power amplifier 41 of the present invention, the output side microstrip line L13 is divided into two in the middle, and the divided gaps are connected by the resistor R45 and the inductor L45. Is characterized by.

In FIG. 7, C15 is a capacitor component generated in the gap of the divided output side microstrip line L13, R45 is a resistor connecting between the divided output side microstrip lines L13, and L45 is also divided. 3 shows an inductor for connecting the output side microstrip lines L13. In this way, the output side microstrip line L13, which is the distributed constant line forming the output matching circuit 13, is divided in the middle, and the resistor R45 and the inductor L45 are provided between the divided output side microstrip lines L13.
Since the inductor L45 and the resistor R45 form a parallel circuit 48, the impedance value of the inductor L45 is high in a high frequency signal, that is, in a high frequency range, and as a result, the resistor R45 and the inductor L45 are connected. The combined impedance of the configured parallel circuit 48 approaches the value of the resistor R45 without limit. Therefore, by matching the resistance value of the resistor R45 with the resistance value of the load resistor connected to the output terminal 17, matching with the load resistor (not shown) connected to the output terminal 17 can be achieved.

On the other hand, at the frequency on the low frequency side, the impedance value of the inductor L45 becomes low, and as a result, the combined impedance of the parallel circuit 48 composed of the resistor R45 and the inductor L45 becomes low, and the microstrip line L13. Also, the output matching circuit 13 composed of L14 and the capacitor C14 can match with the load resistance (not shown) connected to the output terminal 17. As a result,
Further higher performance and wider bandwidth can be realized.

An example of the parallel circuit 48 in the fourth high frequency power amplifier 41 of the present invention will be described with reference to the side view shown in FIG.

FIG. 8 shows how to determine the value of the inductor L45, for example. The inductor L45 needs to have a sufficiently high impedance value at high frequencies. For example, with an inductor of 10 μH, the impedance becomes maximum at about 50 MHz. When the load resistance connected to the output terminal 17 is 50Ω, the resistance R15 is set to 50Ω.

With the parallel circuit 48 thus constructed, for high frequency frequencies, the output terminals are provided by the microstrip lines L13 and L14 and the capacitor C14.
Match the load resistance of 50Ω connected to 17. Further, in the low frequency range, the impedance of the inductor L45 becomes high, and the combined impedance of the parallel circuit 48 approaches the resistance value of the resistor R45, that is, 50Ω in this example, and is connected to the output terminal 17. It is possible to match the resistance value of the load resistance of 50Ω.

As a result, both the high frequency band and the low frequency band can be matched with the load resistance connected to the output terminal 17,
It is possible to meet the demand for higher performance and wider bandwidth of high frequency power amplifiers.

The high frequency power amplifier of the present invention is not limited to the above-described embodiments, but various modifications and improvements can be made without departing from the scope of the present invention. For example, the distributed constant line that constitutes the input matching circuit 12, the output matching circuit 13, and the DC current bias circuit is not limited to the microstrip line shown in the above example, and a strip line formed in the dielectric substrate may be used. Good.

Further, as the high frequency amplifying section, in addition to the high frequency transistors such as the field effect transistors shown in the above example, a high frequency power amplifying circuit having a similar high frequency power amplifying function may be used.

[0060]

According to the first high frequency power amplifier of the present invention, the output matching circuit is composed of the distributed constant lines divided on the way and the resistors connecting the divided distributed constant lines. Therefore, the parallel circuit is composed of the capacitor component and the resistance generated in the gap of the divided distributed constant line, and the impedance connected to the external terminal is propagated by propagating the capacitor component in the high frequency range. Since the capacitor component is not propagated in the low frequency range, the combined impedance of the parallel circuit approaches the resistance value of the resistor infinitely, and the resistance value of this resistor becomes the load resistance connected to the output terminal. Matching can be achieved by making them equal. As a result, both high and low frequencies can be matched with the load resistance connected to the output terminal, and the high performance and wide band of the high frequency power amplifier can be realized.

Further, according to the second high frequency power amplifier of the present invention, the output matching circuit is composed of a distributed constant line divided on the way, and a resistor and a capacitor connecting the divided distributed constant lines. Therefore, the parallel circuit is composed of these capacitors and resistors,
The high frequency component propagates through the capacitor as it is, and the low frequency component can match the load resistance connected to the output terminal through the resistor in both high and low frequency ranges. It is possible to realize further higher performance and wider band.

Further, according to the third high frequency power amplifier of the present invention, the output matching circuit is composed of a distributed constant line divided in the middle, and a resistor and a wire connecting the divided distributed constant lines. As a result, a parallel circuit is formed by the inductor component and the resistance of the wire itself, and the high frequency component has a high impedance in the inductor component, and thus is composed of the inductor component and the resistance of the wire itself. The combined impedance of the parallel circuit has almost a resistance value, and matching can be achieved by using a resistance having the same resistance value as the load resistance connected to the output terminal. In addition, since the low frequency component has a low impedance in the inductor component, it propagates as it is, and it is possible to match the load resistance connected to the output terminal with both the high and low frequencies, and It is possible to realize higher performance and wider band of the amplifier.

Further, according to the fourth high frequency power amplifier of the present invention, the output matching circuit is composed of a distributed constant line divided in the middle, and a resistor and an inductor connecting the divided distributed constant lines. As a result, these inductors and resistors form a parallel circuit,
Since the high-frequency component has a high impedance in the inductor, the combined impedance of the parallel circuit consisting of the inductor and the resistor has a resistance value that is almost the same as the load resistance connected to the output terminal. Matching can be achieved by using them. In addition, the low-frequency component has a low impedance in the inductor, so it propagates as it is, and it is possible to match the load resistance connected to the output terminal with both the high and low frequencies. It is possible to realize further higher performance and wider band.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing a circuit configuration of an example of an embodiment of a first high frequency power amplifier of the present invention.

FIG. 2 is a side view showing an example of a parallel circuit in the first high-frequency power amplifier of the present invention.

FIG. 3 is a circuit diagram showing a circuit configuration of an example of an embodiment of a second high frequency power amplifier of the present invention.

FIG. 4 is a side view showing an example of a parallel circuit in the second high-frequency power amplifier of the present invention.

FIG. 5 is a circuit diagram showing a circuit configuration of an example of an embodiment of a third high-frequency power amplifier of the present invention.

FIG. 6 is a side view showing an example of a parallel circuit in a third high frequency power amplifier of the present invention.

FIG. 7 is a circuit diagram showing a circuit configuration of an example of an embodiment of a fourth high frequency power amplifier of the present invention.

FIG. 8 is a side view showing an example of a parallel circuit in a fourth high frequency power amplifier of the present invention.

FIG. 9 is a circuit diagram showing a circuit configuration of an example of a conventional high frequency power amplifier.

[Explanation of symbols]

Q11 ・ ・ ・ High frequency transistor (high frequency amplifier) 12 ・ ・ ・ Input matching circuit 13 ・ ・ ・ Output matching circuit L12 ・ ・ ・ Drain microstrip line (DC current bias circuit) L13 ・ ・ ・ Output side microstrip line (Distribution) Constant line) C15 ... Capacitor components R15, R25, R35, R45 between the gaps of the output side microstrip line L13 ... Resistor C25 ... Capacitor W35 ... Wire L45 ... Inductors 18, 28, 38 , 48 ... Parallel circuit

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 5J067 AA04 AA41 CA62 CA75 FA00                       HA09 HA25 HA29 HA32 HA33                       KA29 KA66 KA68 LS12 MA21                       QA04 QS05 SA13                 5J091 AA04 AA41 CA62 CA75 FA00                       HA09 HA25 HA29 HA32 HA33                       KA29 KA66 KA68 MA21 QA04                       SA13                 5J500 AA04 AA41 AC62 AC75 AF00                       AH09 AH25 AH29 AH32 AH33                       AK29 AK66 AK68 AM21 AQ04                       AS13

Claims (4)

[Claims] 1. A high frequency amplifier for amplifying a high frequency signal from an input electrode and transmitting it from an output electrode, and an input matching circuit connected to the input electrode for impedance matching with respect to a fundamental frequency of the high frequency signal. And an output matching circuit connected to the output electrode and a direct current bias circuit connected to the output electrode, and the output matching circuit is a distributed constant line divided in the middle and these are divided. A power amplifier for high frequency, comprising: a resistor connecting between distributed constant lines. 2. A high frequency amplifier for amplifying a high frequency signal from an input electrode and transmitting it from an output electrode, and an input matching circuit connected to the input electrode for impedance matching with respect to a fundamental frequency of the high frequency signal. And an output matching circuit connected to the output electrode and a direct current bias circuit connected to the output electrode, and the output matching circuit is a distributed constant line divided in the middle and these are divided. A high frequency power amplifier comprising a resistor and a capacitor connecting between distributed constant lines. 3. A high frequency amplifier for amplifying a high frequency signal from an input electrode and transmitting it from an output electrode, and an input matching circuit connected to the input electrode for impedance matching with respect to a fundamental frequency of the high frequency signal. And an output matching circuit connected to the output electrode and a direct current bias circuit connected to the output electrode, and the output matching circuit is a distributed constant line divided in the middle and these are divided. A high-frequency power amplifier comprising a resistor and a wire for connecting between distributed constant lines. 4. A high frequency amplifier for amplifying a high frequency signal from an input electrode and sending it from an output electrode, and an input matching circuit connected to the input electrode for impedance matching with respect to a fundamental frequency of the high frequency signal. And an output matching circuit connected to the output electrode and a direct current bias circuit connected to the output electrode, and the output matching circuit is a distributed constant line divided in the middle and these are divided. A high frequency power amplifier comprising a resistor and an inductor connecting between distributed constant lines.