Radio frequency power amplification circuit and radio frequency chip

Abstract

The application provides a radio frequency power amplifier circuit and a radio frequency chip, wherein the radio frequency power amplifier circuit comprises input matching circuit, first stage amplifier, first inter-stage matching circuit, second stage amplifier, second inter-stage matching circuit, third stage amplifier and output matching circuit which are connected in sequence; the radio frequency power amplifier circuit further comprises control module, direct current power supply module, first bias circuit, second bias circuit and third bias circuit; the first bias circuit comprises bias input matching circuit, power amplifier, first inductor, first bias unit, bias output matching circuit, power detection circuit, voltage control circuit and second bias unit. The application can improve the robustness of the radio frequency high power amplifier circuit.

Description

Technical Field

[0001] This invention relates to the field of communication technology, and in particular to a radio frequency power amplifier circuit and a radio frequency chip. Background Technology

[0002] With the continuous development of communication technology, the requirements for communication distance and quality of communication equipment are becoming increasingly higher. This leads to increasingly stringent requirements for radio frequency power in communication equipment. As the requirements for radio frequency power continue to increase, the overall radio frequency power tolerance and robustness of power amplifiers are facing great challenges.

[0003] like Figure 1 The power amplifier circuit in the aforementioned technology includes, in sequence, a capacitor C1, a first-stage power amplifier, a first-stage inter-stage matching circuit, a second-stage power amplifier, a second-stage inter-stage matching circuit, a third-stage power amplifier, an output matching circuit, a bias circuit A connected to the input terminal of the first-stage power amplifier, a bias circuit B connected to the input terminal of the second-stage power amplifier, a bias circuit C connected to the input terminal of the third-stage power amplifier, a control module for receiving logic instructions and providing control voltages to the bias circuits A, B, and C respectively, and a battery for powering the control module, the first-stage power amplifier, the second-stage power amplifier, and the third-stage power amplifier respectively.

[0004] like Figure 2 As shown, bias circuits A, B, and C each include resistor R1, transistor Q1, transistor Q2, transistor Q3, and capacitor C2. The base and collector of transistors Q1 and Q2 are shorted to form diodes for rectification, and both are powered and controlled by the control module. Transistor Q3 serves as the bias drive stage of the power amplifier and is powered by the battery. Capacitor C2 is a linearization capacitor to improve linearity.

[0005] In practical applications, the above power amplifier circuits, including bias circuits A, B, and C, are identical and provide the same bias voltage. Figure 3 As shown, when the power amplifier circuit reaches a saturation power of 35dBm, the nonlinear region at the saturation power is not within the normal operating range of the power amplifier circuit, and the power compression at this point is severe, which has a significant impact on the robustness of the power amplifier circuit. Summary of the Invention

[0006] To address the shortcomings of the aforementioned related technologies, this invention proposes an RF power amplifier circuit and an RF chip to solve the problem that the power amplifier circuit in the related technologies has a significant impact on its robustness in practical applications.

[0007] To address the aforementioned technical problems, in a first aspect, the present invention provides a radio frequency power amplifier circuit, comprising an input matching circuit, a first-stage amplifier, a first-stage inter-matching circuit, a second-stage amplifier, a second-stage inter-matching circuit, a third-stage amplifier, and an output matching circuit connected in sequence; the radio frequency power amplifier circuit further comprises a control module, a DC power supply module, a first bias circuit, a second bias circuit, and a third bias circuit.

[0008] The input terminal of the control module is used to receive external logic enable signals, and control the first bias circuit, the second bias circuit and the third bias circuit to provide bias voltages for the first stage amplifier, the second stage amplifier and the third stage amplifier respectively according to the received external logic enable signals.

[0009] The DC power supply module is used to supply power to the control module, the first stage amplifier, the second stage amplifier and the third stage amplifier respectively;

[0010] The first bias circuit includes a bias input matching circuit, a power amplifier, a first inductor, a first bias unit, a bias output matching circuit, a power detection circuit, a voltage control circuit, and a second bias unit.

[0011] The input terminal of the bias input matching circuit is connected to the input terminal of the input matching circuit;

[0012] The first input terminal of the power amplifier is connected to the output terminal of the bias input matching circuit.

[0013] The first end of the first inductor is connected to the output end of the power amplifier;

[0014] The input terminal of the first bias unit is connected to the second terminal of the first inductor and then connected to the output terminal of the control module. The output terminal of the first bias unit is connected to the input terminal of the power amplifier to provide a bias voltage for the power amplifier.

[0015] The input terminal of the bias output matching circuit is connected to the output terminal of the power amplifier;

[0016] The first input terminal of the power detection circuit is connected to the output terminal of the bias output matching circuit, and the second input terminal of the power detection circuit is connected to the output terminal of the control module, which is used to convert the received radio frequency signal into voltage through detection.

[0017] The input terminal of the voltage control circuit is connected to the output terminal of the power detection circuit, and is used to control the power detection circuit to turn on or off according to the voltage converted by the power detection circuit.

[0018] The first input terminal of the second bias unit is connected to the output terminal of the voltage control circuit, the second input terminal of the second bias unit is connected to the output terminal of the control module, the third input terminal of the second bias unit is connected to the output terminal of the DC power supply module, and the output terminal of the second bias unit is connected to the input terminal of the first stage amplifier.

[0019] The voltage control circuit is used to pull down the bias voltage output by the second bias unit when it is turned on, thereby turning off the first stage amplifier. When the voltage control circuit is turned off, the second bias unit outputs a bias voltage, thereby turning on the first stage amplifier.

[0020] Preferably, the bias input matching circuit includes a first capacitor; the first terminal of the first capacitor serves as the input terminal of the bias input matching circuit, and the second terminal of the first capacitor serves as the output terminal of the bias input matching circuit.

[0021] The power amplifier includes a first transistor; the base of the first transistor serves as the input terminal of the power amplifier, the collector of the first transistor serves as the output terminal of the power amplifier, and the emitter of the first transistor is grounded.

[0022] Preferably, the first bias unit includes a second transistor and a first resistor;

[0023] The emitter of the second transistor is grounded, and the base of the second transistor is connected to the collector of the second transistor and serves as the output terminal of the first bias unit.

[0024] The first end of the first resistor is connected to the collector of the second transistor, and the second end of the first resistor serves as the input of the first bias unit.

[0025] Preferably, the bias output matching circuit includes a second capacitor, a third capacitor, and a second inductor;

[0026] The first terminal of the second capacitor serves as the input terminal of the bias output matching circuit.

[0027] The first terminal of the third capacitor is connected to the second terminal of the second capacitor, and the second terminal of the third capacitor serves as the output terminal of the bias output matching circuit.

[0028] The first end of the second inductor is connected to the second end of the second capacitor, and the second end of the second inductor is grounded.

[0029] Preferably, the power detection circuit includes a third transistor, a second resistor, a fourth transistor, a third resistor, and a fourth resistor;

[0030] The collector of the third transistor serves as the first input terminal of the power detector circuit, the emitter of the third transistor is grounded, and the base of the third transistor is connected to the collector of the third transistor.

[0031] The first terminal of the second resistor is connected to the base of the third transistor;

[0032] The base of the fourth transistor is connected to the second terminal of the second resistor, the collector of the fourth transistor serves as the output terminal of the power detector circuit, and the emitter of the fourth transistor is grounded.

[0033] The first end of the third resistor and the first end of the fourth resistor together serve as the second input terminal of the power detector circuit. The second end of the third resistor is connected to the collector of the third transistor, and the second end of the fourth resistor is connected to the collector of the fourth transistor.

[0034] Preferably, the voltage control circuit includes a fifth resistor and a fifth transistor;

[0035] The first terminal of the fifth resistor serves as the input terminal of the voltage control circuit;

[0036] The base of the fifth transistor is connected to the second end of the fifth resistor, the collector of the fifth transistor serves as the output terminal of the voltage control circuit, and the emitter of the fifth transistor is grounded.

[0037] Preferably, the second bias unit includes a sixth transistor, a seventh transistor, a sixth resistor, a fourth capacitor, and an eighth transistor;

[0038] The collector of the sixth transistor serves as the first input terminal of the second bias unit, and the base of the sixth transistor is connected to the collector of the sixth transistor.

[0039] The collector of the seventh transistor is connected to the emitter of the sixth transistor, the base of the seventh transistor is connected to the collector of the seventh transistor, and the emitter of the seventh transistor is grounded.

[0040] The first end of the sixth resistor serves as the second input terminal of the second bias unit, and the second end of the sixth resistor is connected to the collector of the sixth transistor.

[0041] The first terminal of the fourth capacitor is connected to the base of the sixth transistor, and the second terminal of the fourth capacitor is grounded.

[0042] The base of the eighth transistor is connected to the base of the sixth transistor, the emitter of the eighth transistor serves as the third input terminal of the second bias unit, and the emitter of the eighth transistor serves as the output terminal of the second bias unit.

[0043] Preferably, the RF power amplifier circuit further includes a first back hole, a second back hole, and a third back hole, wherein the first back hole, the second back hole, and the third back hole are connected in parallel with the first stage amplifier, the second stage amplifier, and the third stage amplifier, respectively, and then grounded.

[0044] Preferably, the second bias circuit includes a seventh resistor, a ninth transistor, a thirteenth transistor, a fifth capacitor, and an eleventh transistor.

[0045] The first end of the seventh resistor is connected to the output end of the control module;

[0046] The collector of the ninth transistor is connected to the second terminal of the seventh resistor, and the base of the ninth transistor is connected to the collector of the ninth transistor.

[0047] The collector of the thirteenth transistor is connected to the emitter of the ninth transistor, the base of the thirteenth transistor is connected to the collector of the thirteenth transistor, and the emitter of the thirteenth transistor is grounded.

[0048] The first terminal of the fifth capacitor is connected to the base of the ninth transistor, and the second terminal of the fifth capacitor is grounded.

[0049] The base of the eleventh transistor is connected to the base of the ninth transistor, the collector of the eleventh transistor is connected to the output terminal of the DC power supply module, and the emitter of the eleventh transistor is connected to the input terminal of the second-stage amplifier and provides a bias voltage for the second-stage amplifier.

[0050] Secondly, the present invention provides an radio frequency chip, which includes the radio frequency power amplifier circuit described above.

[0051] Compared with related technologies, the RF power amplifier circuit in this invention defines a first bias circuit comprising a bias input matching circuit, a power amplifier, a first inductor, a first bias unit, a bias output matching circuit, a power detection circuit, a voltage control circuit, and a second bias unit. It also defines the connection method of the first bias circuit and specifies that the power detection circuit converts the received RF signal into voltage through detection. The voltage control circuit controls the conduction or de-conduction of the power detection circuit based on the voltage converted by the power detection circuit. When the voltage control circuit is de-converted, the second bias unit outputs a bias voltage, thereby turning on the first-stage amplifier. Thus, when the first-stage amplifier is turned off or on, the subsequent second-stage and third-stage amplifiers will also be turned off or on, achieving the function of controlling the RF power amplifier circuit to conduct or de-convert based on the input RF signal. This allows the RF power amplifier circuit to automatically shut down when it reaches saturation power, thereby improving the robustness of the RF power amplifier circuit, protecting the RF power amplifier circuit and its applied RF chips, and enabling its application in higher power system environments. Attached Figure Description

[0052] The present invention will now be described in detail with reference to the accompanying drawings. The above and other aspects of the present invention will become clearer and more readily understood through the detailed description following the accompanying drawings. In the drawings:

[0053] Figure 1 This is a block diagram illustrating the principle of a power amplifier circuit in related technologies.

[0054] Figure 2 This is a circuit diagram of any one of the bias circuits A, B, and C in the power amplifier circuit of the related technology.

[0055] Figure 3 The power simulation curves for power amplifier circuits in related technologies are shown.

[0056] Figure 4 A schematic block diagram of a radio frequency power amplifier circuit provided in an embodiment of the present invention;

[0057] Figure 5 A circuit diagram of the first bias circuit in the radio frequency power amplifier circuit provided in an embodiment of the present invention;

[0058] Figure 6 A circuit diagram of the second bias circuit in the radio frequency power amplifier circuit provided in the embodiment of the present invention;

[0059] Figure 7 A comparison of power simulation curves between the power amplifier circuit provided for related technologies and the radio frequency power amplifier circuit provided in the embodiments of the present invention;

[0060] Figure 8The simulation curves of the input and output power of the fourth transistor in the radio frequency power amplifier circuit provided in the embodiment of the present invention are shown. Detailed Implementation

[0061] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein in the specification of the application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "comprising" and "having," and any variations thereof, in the specification, claims, and foregoing drawings of this application, are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the specification, claims, or foregoing drawings of this application are used to distinguish different objects, not to describe a particular order.

[0062] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0063] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0064] Example 1

[0065] This invention provides an RF power amplifier circuit 100, combined with... Figures 4 to 6 As shown, it includes an input matching circuit 1, a first-stage amplifier 2, a first-stage inter-stage matching circuit 3, a second-stage amplifier 4, a second-stage inter-stage matching circuit 5, a third-stage amplifier 6, and an output matching circuit 7 connected in sequence; the RF power amplifier circuit 100 also includes a control module 8, a DC power supply module 9, a first bias circuit 10, a second bias circuit 11, and a third bias circuit 12.

[0066] Among them, such as Figure 4 As shown, the input matching circuit 1 includes a sixth capacitor C6. The first end of the sixth capacitor C6 serves as the input terminal of the input matching circuit 1 and is used to receive radio frequency signals. The second end of the sixth capacitor C6 serves as the output terminal of the input matching circuit 1.

[0067] The input terminal of the control module 8 is used to receive external logic enable signals, and according to the received external logic enable signals, it controls the first bias circuit 10, the second bias circuit 11 and the third bias circuit 12 to provide bias voltages for the first stage amplifier 2, the second stage amplifier 4 and the third stage amplifier 6 respectively.

[0068] The DC power supply module 9 is used to supply power to the control module 8, the first-stage amplifier 2, the second-stage amplifier 4, and the third-stage amplifier 6 respectively.

[0069] The first bias circuit 10 includes a bias input matching circuit 101, a power amplifier 102, a first inductor L1, a first bias unit 103, a bias output matching circuit 104, a power detector circuit 105, a voltage control circuit 106, and a second bias unit 107.

[0070] The input terminal of the bias input matching circuit 101 is connected to the input terminal of the input matching circuit 1.

[0071] The bias input matching circuit 101 includes a first capacitor C1; the first end of the first capacitor C1 serves as the input terminal of the bias input matching circuit 101, and the second end of the first capacitor C1 serves as the output terminal of the bias input matching circuit 101.

[0072] The first input terminal of the power amplifier 102 is connected to the output terminal of the bias input matching circuit 101.

[0073] The power amplifier 102 includes a first transistor Q1; the base of the first transistor Q1 serves as the input terminal of the power amplifier 102, the collector of the first transistor Q1 serves as the output terminal of the power amplifier 102, and the emitter of the first transistor Q1 is grounded.

[0074] The first transistor Q1 acts as an amplification network to amplify the radio frequency signal coupled by the first capacitor C1.

[0075] The first terminal of the first inductor L1 is connected to the output terminal of the power amplifier 102.

[0076] The input terminal of the first bias unit 103 is connected to the second terminal of the first inductor L1 and then connected to the output terminal of the control module 8. The output terminal of the first bias unit 103 is connected to the input terminal of the power amplifier 102 to provide bias voltage for the power amplifier 102.

[0077] The first bias unit 103 includes a second transistor Q2 and a first resistor R1.

[0078] The emitter of the second transistor Q2 is grounded, and the base of the second transistor Q2 is connected to the collector of the second transistor Q2 and serves as the output terminal of the first bias unit 103.

[0079] The first end of the first resistor R1 is connected to the collector of the second transistor Q2, and the second end of the first resistor R1 serves as the input terminal of the first bias unit 103.

[0080] The first bias unit 103 serves as the base bias unit for the first transistor Q1, and is used to provide a bias voltage for the first transistor Q1.

[0081] The input of the bias output matching circuit 104 is connected to the output of the power amplifier 102.

[0082] The bias output matching circuit 104 includes a second capacitor C2, a third capacitor C3, and a second inductor L2.

[0083] The first terminal of the second capacitor C2 serves as the input terminal of the bias output matching circuit 104.

[0084] The first terminal of the third capacitor C3 is connected to the second terminal of the second capacitor C2, and the second terminal of the third capacitor C3 serves as the output terminal of the bias output matching circuit 104.

[0085] The first end of the second inductor L2 is connected to the second end of the second capacitor C2, and the second end of the second inductor L2 is grounded; the second inductor L2 is used to block the radio frequency signal from being transmitted to the control module 8.

[0086] The bias output matching circuit 104 is used to adjust the output signal of the first transistor Q1, thereby providing the power detection circuit 105 with an appropriate power level.

[0087] The first input terminal of the power detection circuit 105 is connected to the output terminal of the bias output matching circuit 104, and the second input terminal of the power detection circuit 105 is connected to the output terminal of the control module 8. It is used to convert the received radio frequency signal into voltage through detection. Mainly, when the input radio frequency signal is too large, it is converted into voltage through detection, so that the collector of the fourth transistor Q4 outputs voltage to control the conduction or cutoff of the fifth transistor Q5.

[0088] The power detection circuit 105 includes a third transistor Q3, a second resistor R2, a fourth transistor Q4, a third resistor R3, and a fourth resistor R4.

[0089] The collector of the third transistor Q3 serves as the first input terminal of the power detector circuit 105. The emitter of the third transistor Q3 is grounded, and the base of the third transistor Q3 is connected to the collector of the third transistor Q3.

[0090] The first end of the second resistor R2 is connected to the base of the third transistor Q3.

[0091] The base of the fourth transistor Q4 is connected to the second end of the second resistor R2, the collector of the fourth transistor Q4 serves as the output terminal of the power detector circuit 105, and the emitter of the fourth transistor Q4 is grounded.

[0092] The first end of the third resistor R3 and the first end of the fourth resistor R4 together serve as the second input terminal of the power detector circuit 105. The second end of the third resistor R3 is connected to the collector of the third transistor Q3, and the second end of the fourth resistor R4 is connected to the collector of the fourth transistor Q4.

[0093] The working principle of the power detection circuit 105 is as follows: the first capacitor C1 serves as a DC blocking and coupling capacitor for coupling signals. The capacitance of the first capacitor C1 can control the magnitude of the coupled power. After being amplified by the first transistor Q1, it is rectified by the third transistor Q3. The third resistor R3 serves as the bias control resistor for the third transistor Q3, controlling the magnitude of the rectification by the third transistor Q3. The second resistor R2 serves as the bias resistor for the base of the fourth transistor Q4, controlling the amplification effect of the fourth transistor Q4. The fourth resistor R4 serves as the voltage control resistor for the collector of the fourth transistor Q4, controlling the magnitude of the output voltage of the fourth transistor Q4.

[0094] The input terminal of the voltage control circuit 106 is connected to the output terminal of the power detection circuit 105, and is used to control its conduction or cutoff according to the voltage converted by the power detection circuit 105.

[0095] The voltage control circuit 106 includes a fifth resistor R5 and a fifth transistor Q5.

[0096] The first terminal of the fifth resistor R5 serves as the input terminal of the voltage control circuit 106.

[0097] The base of the fifth transistor Q5 is connected to the second end of the fifth resistor R5. The collector of the fifth transistor Q5 serves as the output terminal of the voltage control circuit 106, and the emitter of the fifth transistor Q5 is grounded.

[0098] The fifth transistor Q5 and the fifth resistor R5 are controlled by the output voltage of the fourth transistor Q4. When the output voltage of the fourth transistor Q4 is greater than the turn-on voltage of the fifth transistor Q5, the fifth transistor Q5 turns on, pulling the collector voltage of the sixth transistor Q6 to ground, thereby turning off the second bias unit 107, preventing it from providing bias voltage to the first-stage amplifier 2, and thus turning off the first-stage amplifier 2. When the fifth transistor Q5 turns off, the second bias unit 107 turns on, correspondingly providing bias voltage to the first-stage amplifier 2, and also turning on the first-stage amplifier 2. The fifth resistor R5 is used to control the conduction strength of the fifth transistor Q5 and to prevent leakage.

[0099] The first input terminal of the second bias unit 107 is connected to the output terminal of the voltage control circuit 106, the second input terminal of the second bias unit 107 is connected to the output terminal of the control module 8, the third input terminal of the second bias unit 107 is connected to the output terminal of the DC power supply module 9, and the output terminal of the second bias unit 107 is connected to the input terminal of the first stage amplifier 2 and provides bias voltage for the first stage amplifier 2.

[0100] like Figure 5 As shown, the second bias unit 107 includes a sixth transistor Q6, a seventh transistor Q7, a sixth resistor R6, a fourth capacitor C4, and an eighth transistor Q8.

[0101] The collector of the sixth transistor Q6 serves as the first input terminal of the second bias unit 107, and the base of the sixth transistor Q6 is connected to the collector of the sixth transistor Q6.

[0102] The collector of the seventh transistor Q7 is connected to the emitter of the sixth transistor Q6, the base of the seventh transistor Q7 is connected to the collector of the seventh transistor Q7, and the emitter of the seventh transistor Q7 is grounded.

[0103] The first end of the sixth resistor R6 serves as the second input terminal of the second bias unit 107, and the second end of the sixth resistor R6 is connected to the collector of the sixth transistor Q6.

[0104] The first terminal of the fourth capacitor C4 is connected to the base of the sixth transistor Q6, and the second terminal of the fourth capacitor C4 is grounded.

[0105] The base of the eighth transistor Q8 is connected to the base of the sixth transistor Q6. The emitter of the eighth transistor Q8 serves as the third input terminal of the second bias unit 107, and the emitter of the eighth transistor Q8 serves as the output terminal of the second bias unit 107.

[0106] The voltage control circuit 106 is used to pull down the bias voltage output by the second bias unit 107 when it is turned on, thereby turning off the first stage amplifier 2. When the voltage control circuit 106 is turned off, the second bias unit 107 outputs a bias voltage, thereby turning on the first stage amplifier 2.

[0107] The second bias circuit 11 includes a seventh resistor R7, a ninth transistor Q9, a thirteenth transistor Q10, a fifth capacitor C5, and an eleventh transistor Q11.

[0108] The first end of the seventh resistor R7 is connected to the output terminal of the control module 8.

[0109] The collector of transistor Q9 is connected to the second terminal of resistor R7, and the base of transistor Q9 is connected to the collector of transistor Q9.

[0110] The collector of the thirteenth transistor Q10 is connected to the emitter of the ninth transistor Q9, the base of the thirteenth transistor Q10 is connected to the collector of the thirteenth transistor Q10, and the emitter of the thirteenth transistor Q10 is grounded.

[0111] The first terminal of the fifth capacitor C5 is connected to the base of the ninth transistor Q9, and the second terminal of the fifth capacitor C5 is grounded.

[0112] The base of the eleventh transistor Q11 is connected to the base of the ninth transistor Q9, the collector of the eleventh transistor Q11 is connected to the output of the DC power supply module 9, and the emitter of the eleventh transistor Q11 is connected to the input of the second-stage amplifier 4, providing a bias voltage for the second-stage amplifier 4.

[0113] The circuit structure of the third bias circuit 12 is similar to that of the second bias circuit 11. The difference is that the emitter of the eleventh transistor Q11 in the third bias circuit 12 is connected to the input terminal of the third stage amplifier 6 and provides bias voltage for the third stage amplifier 6. The other components and connection methods are not described in detail here.

[0114] The radio frequency power amplifier circuit 100 also includes a first back hole 13, a second back hole 14 and a third back hole 15. The first back hole 13, the second back hole 14 and the third back hole 15 are connected in parallel with the first stage amplifier 2, the second stage amplifier 4 and the third stage amplifier 6 respectively and then grounded.

[0115] like Figure 7 As shown, it is evident that when the output power reaches 34.5 dBm or the input power exceeds -2 dBm, the attenuation of the RF power amplifier circuit 100 in this invention is significant, and it increases with increasing input power. Figure 8 As shown, in the RF power amplifier circuit 100 of the present invention, as the input power increases, the output voltage of the power detection circuit 105 also increases. Since the conduction voltage of the fifth transistor Q5 is around 1.2V, after exceeding this threshold, the fifth transistor Q5 conducts, thereby pulling down the bias voltage of the node of the sixth transistor Q6, which is equivalent to pulling down the bias voltage output by the second bias unit 107, thereby turning off the RF power amplifier circuit 100, so as to protect the RF power amplifier circuit 100 and the RF signals used therein, and can be applied to higher power system environments.

[0116] Compared with related technologies, the RF power amplifier circuit 100 in this embodiment defines the first bias circuit 10 as including a bias input matching circuit 101, a power amplifier 102, a first inductor L1, a first bias unit 103, a bias output matching circuit 104, a power detection circuit 105, a voltage control circuit 106, and a second bias unit 107, and defines the connection method of the first bias circuit 10. It also defines the power detection circuit 105 as converting the received RF signal into voltage through detection, and the voltage control circuit 106 as controlling its conduction or de-conduction according to the voltage converted by the power detection circuit 105. When the voltage control circuit 106 is de-converted, the second bias unit 107 outputs a bias voltage, thereby turning on the first bias unit 107. The first-stage amplifier 2 is used so that when the first-stage amplifier 2 is turned off or on, the subsequent second-stage amplifier 4 and third-stage amplifier 6 will also be turned off or on, thereby controlling the RF power amplifier circuit 100 to turn on or off according to the input RF signal. In this way, when the RF power amplifier circuit 100 reaches the saturation power, it will achieve the effect of automatic shutdown, thereby improving the robustness of the RF power amplifier circuit 100. This is equivalent to improving the stability and reliability of the RF power amplifier circuit 100 under the corresponding operating conditions, thus protecting the RF power amplifier circuit 100 and the RF chip it is used in, and enabling its application in higher power system environments. At the same time, the RF power amplifier circuit 100 in this embodiment has a simple structure and is easy to implement.

[0117] Example 2

[0118] This invention provides an RF chip that includes the RF power amplifier circuit 100 described in Embodiment 1. Since the RF chip in this embodiment includes the RF power amplifier circuit 100 described in Embodiment 1, it can achieve the same technical effects as the RF power amplifier circuit 100 described in Embodiment 1, and will not be described in detail here.

[0119] It should be noted that the various embodiments described above with reference to the accompanying drawings are merely illustrative of the present invention and not intended to limit its scope. Those skilled in the art should understand that any modifications or equivalent substitutions made to the present invention without departing from its spirit and scope should be included within the scope of the present invention. Furthermore, unless the context otherwise requires, words appearing in the singular include those in the plural, and vice versa. Additionally, unless specifically stated otherwise, all or part of any embodiment may be used in conjunction with all or part of any other embodiment.

Claims

1. A radio frequency power amplifier circuit, comprising an input matching circuit, a first-stage amplifier, an inter-stage matching circuit, a second-stage amplifier, an inter-stage matching circuit, a third-stage amplifier, and an output matching circuit connected in sequence; characterized in that, The radio frequency power amplifier circuit also includes a control module, a DC power supply module, a first bias circuit, a second bias circuit, and a third bias circuit. The input terminal of the control module is used to receive external logic enable signals, and control the first bias circuit, the second bias circuit and the third bias circuit to provide bias voltages for the first stage amplifier, the second stage amplifier and the third stage amplifier respectively according to the received external logic enable signals. The DC power supply module is used to supply power to the control module, the first stage amplifier, the second stage amplifier and the third stage amplifier respectively; The first bias circuit includes a bias input matching circuit, a power amplifier, a first inductor, a first bias unit, a bias output matching circuit, a power detection circuit, a voltage control circuit, and a second bias unit. The input terminal of the bias input matching circuit is connected to the input terminal of the input matching circuit; The input terminal of the power amplifier is connected to the output terminal of the bias input matching circuit; The first end of the first inductor is connected to the output end of the power amplifier; The input terminal of the first bias unit is connected to the second terminal of the first inductor and then connected to the output terminal of the control module. The output terminal of the first bias unit is connected to the input terminal of the power amplifier to provide a bias voltage for the power amplifier. The input terminal of the bias output matching circuit is connected to the output terminal of the power amplifier; The first input terminal of the power detection circuit is connected to the output terminal of the bias output matching circuit, and the second input terminal of the power detection circuit is connected to the output terminal of the control module, which is used to convert the received radio frequency signal into voltage through detection. The input terminal of the voltage control circuit is connected to the output terminal of the power detection circuit, and is used to control the power detection circuit to turn on or off according to the voltage converted by the power detection circuit. The first input terminal of the second bias unit is connected to the output terminal of the voltage control circuit, the second input terminal of the second bias unit is connected to the output terminal of the control module, the third input terminal of the second bias unit is connected to the output terminal of the DC power supply module, and the output terminal of the second bias unit is connected to the input terminal of the first stage amplifier and provides bias voltage to the first stage amplifier. The voltage control circuit is used to pull down the bias voltage output by the second bias unit when it is turned on, thereby turning off the first stage amplifier. When the voltage control circuit is turned off, the second bias unit outputs a bias voltage, thereby turning on the first stage amplifier. The voltage control circuit includes a fifth resistor and a fifth transistor; The first terminal of the fifth resistor serves as the input terminal of the voltage control circuit; The base of the fifth transistor is connected to the second terminal of the fifth resistor, the collector of the fifth transistor serves as the output terminal of the voltage control circuit, and the emitter of the fifth transistor is grounded. The second bias unit includes a sixth transistor, a seventh transistor, a sixth resistor, a fourth capacitor, and an eighth transistor; The collector of the sixth transistor serves as the first input terminal of the second bias unit, and the base of the sixth transistor is connected to the collector of the sixth transistor. The collector of the seventh transistor is connected to the emitter of the sixth transistor, the base of the seventh transistor is connected to the collector of the seventh transistor, and the emitter of the seventh transistor is grounded. The first end of the sixth resistor serves as the second input terminal of the second bias unit, and the second end of the sixth resistor is connected to the collector of the sixth transistor. The first terminal of the fourth capacitor is connected to the base of the sixth transistor, and the second terminal of the fourth capacitor is grounded. The base of the eighth transistor is connected to the base of the sixth transistor, the emitter of the eighth transistor serves as the third input terminal of the second bias unit, and the emitter of the eighth transistor serves as the output terminal of the second bias unit.

2. The radio frequency power amplifier circuit as described in claim 1, characterized in that, The bias input matching circuit includes a first capacitor; the first terminal of the first capacitor serves as the input terminal of the bias input matching circuit, and the second terminal of the first capacitor serves as the output terminal of the bias input matching circuit. The power amplifier includes a first transistor; the base of the first transistor serves as the input terminal of the power amplifier, the collector of the first transistor serves as the output terminal of the power amplifier, and the emitter of the first transistor is grounded.

3. The radio frequency power amplifier circuit as described in claim 1, characterized in that, The first bias unit includes a second transistor and a first resistor; The emitter of the second transistor is grounded, and the base of the second transistor is connected to the collector of the second transistor and serves as the output terminal of the first bias unit. The first end of the first resistor is connected to the collector of the second transistor, and the second end of the first resistor serves as the input of the first bias unit.

4. The radio frequency power amplifier circuit as described in claim 1, characterized in that, The bias output matching circuit includes a second capacitor, a third capacitor, and a second inductor. The first terminal of the second capacitor serves as the input terminal of the bias output matching circuit. The first terminal of the third capacitor is connected to the second terminal of the second capacitor, and the second terminal of the third capacitor serves as the output terminal of the bias output matching circuit. The first end of the second inductor is connected to the second end of the second capacitor, and the second end of the second inductor is grounded.

5. The radio frequency power amplifier circuit as described in claim 1, characterized in that, The power detection circuit includes a third transistor, a second resistor, a fourth transistor, a third resistor, and a fourth resistor; The collector of the third transistor serves as the first input terminal of the power detector circuit, the emitter of the third transistor is grounded, and the base of the third transistor is connected to the collector of the third transistor. The first terminal of the second resistor is connected to the base of the third transistor; The base of the fourth transistor is connected to the second terminal of the second resistor, the collector of the fourth transistor serves as the output terminal of the power detector circuit, and the emitter of the fourth transistor is grounded. The first end of the third resistor and the first end of the fourth resistor together serve as the second input terminal of the power detector circuit. The second end of the third resistor is connected to the collector of the third transistor, and the second end of the fourth resistor is connected to the collector of the fourth transistor.

6. The radio frequency power amplifier circuit as described in claim 1, characterized in that, The radio frequency power amplifier circuit further includes a first back hole, a second back hole, and a third back hole, wherein the first back hole, the second back hole, and the third back hole are connected in parallel with the first stage amplifier, the second stage amplifier, and the third stage amplifier, respectively, and then grounded.

7. The radio frequency power amplifier circuit as described in claim 1, characterized in that, The second bias circuit includes a seventh resistor, a ninth transistor, a thirteenth transistor, a fifth capacitor, and an eleventh transistor; The first end of the seventh resistor is connected to the output end of the control module; The collector of the ninth transistor is connected to the second terminal of the seventh resistor, and the base of the ninth transistor is connected to the collector of the ninth transistor. The collector of the thirteenth transistor is connected to the emitter of the ninth transistor, the base of the thirteenth transistor is connected to the collector of the thirteenth transistor, and the emitter of the thirteenth transistor is grounded. The first terminal of the fifth capacitor is connected to the base of the ninth transistor, and the second terminal of the fifth capacitor is grounded. The base of the eleventh transistor is connected to the base of the ninth transistor, the collector of the eleventh transistor is connected to the output terminal of the DC power supply module, and the emitter of the eleventh transistor is connected to the input terminal of the second-stage amplifier and provides a bias voltage for the second-stage amplifier.

8. A radio frequency chip, characterized in that, The radio frequency chip includes the radio frequency power amplifier circuit as described in any one of claims 1 to 7.

Images