Power amplifier circuit and electronic device

Abstract

The present invention provides a power amplifier circuit and an electronic device. The power amplifier circuit includes a driver stage module, an output stage module, a first bias module, a second bias module, and a bias compensation module. The bias compensation module is configured to be able to monitor the temperature of the output stage module and the temperature of the environment where the power amplifier is located. The bias compensation module accesses a control signal and is electrically connected to the input end of the first bias module. The first bias module accesses a control signal and is electrically connected to the driver stage module. The second bias module accesses a control signal and is electrically connected to the output stage module. The first end of the driver stage module accesses an original input signal, and the second end of the driver stage module is electrically connected to the first end of the output stage module. The second end of the output stage module is directly or indirectly electrically connected to an antenna. A bias compensation current is generated by the bias compensation module so that the gain when the power amplifier circuit switches operating modes tends to be consistent.

Description

Technical Field

[0001] The present invention relates to the field of communication technologies, and in particular, to a power amplifier circuit and an electronic device. Background Art

[0002] GaAs HBT (Heterojunction Bipolar Transistor in Chinese, and Heterojunction Bipolar Transistor in English) is one of the most widely used process technologies for radio frequency power amplifier chips. The traditional two-stage GaAs HBT process radio frequency power amplifier chip includes a driver-stage HBT and an output-stage HBT. The driver-stage HBT and the output-stage HBT are respectively provided with bias currents by different bias circuits. The control end of the bias circuit is electrically connected to the control signal of the radio frequency power amplifier. Furthermore, by controlling the bias circuit, the control of the driver-stage HBT and the output-stage HBT is realized.

[0003] As an amplifying tube, GaAs HBT has the characteristic that its gain decreases as the junction temperature rises. When the radio frequency power amplifier chip is turned on, heat will accumulate inside the chip. For control signals with different duty cycles, the junction temperature of GaAs HBT will also be different. When the duty cycle of the control signal is high, the average junction temperature is higher; when the duty cycle of the control signal is low, the average junction temperature is low. Due to the higher junction temperature, the gain of the traditional radio frequency power amplifier chip will decrease when it is turned on with a high duty cycle.

[0004] In the prior art, generally, a temperature monitoring device is set to detect the ambient temperature, and then the output power is compensated. However, the change in the gain of the radio frequency power amplifier chip is caused by the change in the HBT junction temperature. The prior art cannot fundamentally solve the problem of gain change when the power amplifier switches its working mode (i.e., the duty cycle of the control signal changes). Summary of the Invention

[0005] The present invention provides a power amplifier circuit and an electronic device to solve the problem of gain change when the power amplifier switches its working mode.

[0006] According to a first aspect of the present invention, a power amplifier circuit is provided, including a driver-stage module, an output-stage module, a first bias module, a second bias module, and a bias compensation module;

[0007] The bias compensation module is configured to be able to monitor the temperature of the output-stage module to obtain the output-stage temperature; the bias compensation module is further configured to be able to monitor the temperature of the environment where the power amplifier is located to obtain the ambient temperature;

[0008] The bias compensation module receives a control signal. The bias compensation module is electrically connected to the input end of the first bias module and is configured to: when the duty cycle of the control signal changes, generate a bias compensation current according to the output stage temperature and the ambient temperature, and feedback the bias compensation current to the first bias module; the duty cycle is the duty cycle control signal for the switching between the first level signal and the second level signal in the control signal.

[0009] The first bias module receives the control signal. The first bias module is electrically connected to the driver stage module, and when the control signal is the first level signal, feedback the first bias voltage to the driver stage module according to the bias compensation current.

[0010] The second bias module receives the control signal. The second bias module is electrically connected to the output stage module, and when the control signal is the first level signal, feedback the second bias voltage to the output stage module.

[0011] The first end of the driver stage module receives the original input signal. The second end of the driver stage module is electrically connected to the first end of the output stage module. Based on the first bias voltage, amplify the original input signal to obtain an amplified signal, and transmit the amplified signal to the output stage module.

[0012] The second end of the output stage module is directly or indirectly electrically connected to the antenna. Based on the second bias voltage, amplify the received amplified signal to obtain a target signal, and directly or indirectly transmit the target signal to the antenna.

[0013] Optionally, the bias compensation module includes a temperature difference detection unit and a compensation control unit.

[0014] The temperature difference detection unit is configured to be able to monitor the output stage temperature and the ambient temperature, and generate a temperature difference signal according to the output stage temperature and the ambient temperature. The temperature difference signal characterizes the temperature difference between the output stage temperature and the ambient temperature.

[0015] The output end of the temperature difference detection unit is electrically connected to the first input end of the compensation control unit to transmit the temperature difference signal to the compensation control unit.

[0016] The second input end of the compensation control unit receives the control signal. The output end of the compensation control unit is electrically connected to the input end of the first bias module. When the duty cycle of the control signal changes, generate the bias compensation current according to the temperature difference signal, and feedback the bias compensation current to the first bias module.

[0017] Optionally, the temperature difference detection unit includes a first temperature-sensitive element, a second temperature-sensitive element, and a subtractor.

[0018] The voltage value or resistance value of the first temperature-sensitive element is adapted to the output stage temperature. The first end of the first temperature-sensitive element is electrically connected to the first input terminal of the subtractor, and the second end of the first temperature-sensitive element is grounded.

[0019] The voltage value or resistance value of the second temperature-sensitive element is adapted to the ambient temperature. The first end of the second temperature-sensitive element is electrically connected to the second input terminal of the subtractor, and the second end of the second temperature-sensitive element is grounded.

[0020] The output terminal of the subtractor is electrically connected to the first input terminal of the compensation control unit.

[0021] Optionally, the temperature difference detection unit further includes a first resistor and a second resistor. The first temperature-sensitive element is a first diode, and the second temperature-sensitive element is a second diode.

[0022] The voltage value of the first diode is adapted to the output stage temperature. The positive electrode of the first diode is electrically connected to the first end of the first resistor and the first input terminal of the subtractor, and the negative electrode of the first diode is grounded.

[0023] The voltage value of the second diode is adapted to the ambient temperature. The positive electrode of the second diode is electrically connected to the first end of the second resistor and the second input terminal of the subtractor, and the negative electrode of the second diode is grounded.

[0024] The second ends of the first resistor and the second resistor are electrically connected to a first power supply.

[0025] Optionally, the compensation control unit includes an analog-to-digital converter, a controller, and a current source sub-unit.

[0026] The input terminal of the analog-to-digital converter is electrically connected to the output terminal of the temperature difference detection unit. The enable terminal of the analog-to-digital converter is connected to the control signal. When the duty cycle of the control signal changes, the temperature difference signal is subjected to analog-to-digital conversion to obtain a digital temperature difference signal.

[0027] The output terminal of the analog-to-digital converter is electrically connected to the input terminal of the controller to transmit the digital temperature difference signal to the controller.

[0028] The output terminal of the controller is electrically connected to the input terminal of the current source sub-unit to control the current source sub-unit to generate a bias compensation current according to the digital temperature difference signal.

[0029] The output terminal of the current source sub-unit is electrically connected to the input terminal of the first bias module to feedback the bias compensation current to the first bias module.

[0030] Optionally, the current source sub-unit includes M current sources and M switches. The first end of each switch is electrically connected to the output terminal of the controller, the second end of each switch is electrically connected to the first end of a current source, and the second end of each current source is electrically connected to the input terminal of the first bias module. The controller controls the number of closed switches among the M switches according to the digital temperature difference signal to control the magnitude of the bias compensation current.

[0031] Optionally, the first bias module includes a first bias transistor and a first bias current source.

[0032] The first end of the first bias current source is electrically connected to the second power supply, the controlled end of the first bias current source accesses the control signal, and the second end of the first bias current source is electrically connected to the control electrode of the first bias transistor.

[0033] The control electrode of the first bias transistor is electrically connected to the output terminal of the bias compensation module.

[0034] The first pole of the first bias transistor is electrically connected to the third power supply, and the second pole of the first bias transistor is electrically connected to the first end of the drive stage module.

[0035] Optionally, the second bias module includes a second bias transistor and a second bias current source.

[0036] The first end of the second bias current source is electrically connected to the fourth power supply, the controlled end of the second bias current source accesses the control signal, and the second end of the second bias current source is electrically connected to the control electrode of the second bias transistor.

[0037] The first pole of the second bias transistor is electrically connected to the third power supply, and the second pole of the second bias transistor is electrically connected to the first end of the output stage module.

[0038] Optionally, the drive stage module includes a drive transistor. The control electrode of the drive transistor is electrically connected to the output terminal of the first bias module. The first pole of the drive transistor is directly or indirectly electrically connected to the third power supply, and the second pole of the drive transistor is grounded.

[0039] Optionally, the drive stage module includes a drive inductor. The first end of the drive inductor is electrically connected to the first pole of the drive transistor, and the second end of the drive inductor is electrically connected to the third power supply.

[0040] Optionally, the output stage module includes an output transistor, a control electrode of the output transistor is electrically connected to an output end of the second bias module, a first pole of the output transistor is directly or indirectly electrically connected to a third power supply, and a second pole of the output transistor is grounded.

[0041] Optionally, the output stage module includes an output inductor, a first end of the output inductor is electrically connected to the first pole of the output transistor, and a second end of the output inductor is electrically connected to the third power supply.

[0042] Optionally, the power amplifier circuit further includes a first capacitor and a second capacitor.

[0043] A first end of the first capacitor accesses the original input signal, and a second end of the first capacitor is electrically connected to a first end of the drive stage module.

[0044] A first end of the second capacitor is electrically connected to a second end of the drive stage module, and a second end of the second capacitor is electrically connected to a first end of the output stage module.

[0045] Optionally, the power amplifier circuit further includes an output matching module, a first end of the output matching module is electrically connected to a second end of the output stage module, and a second end of the output matching module is electrically connected to the antenna.

[0046] Optionally, the drive stage module, the output stage module, the first bias module, and the second bias module are disposed on a first circuit board, and the bias compensation module is partially disposed on a second circuit board.

[0047] According to a second aspect of the present invention, there is provided an electronic device including the power amplifier circuit according to the first aspect of the present invention and its optional solutions.

[0048] In the power amplifier circuit and the electronic device provided by the present invention, the bias compensation module monitors the output stage temperature of the output stage module and the ambient temperature where the power amplifier is located. Then, when the duty cycle of the control signal changes, the bias compensation module generates a bias compensation current to compensate the first bias voltage, so as to compensate for the decrease in gain caused by the overhigh temperature of the output stage module by increasing the first bias voltage of the drive stage module, so that the gain tends to be consistent when the power amplifier circuit switches the working mode.

[0049] At the same time, the bias compensation module compensates the first bias voltage of the first bias module. Compared with some solutions where the bias compensation module compensates the second bias voltage of the second bias module, the present invention needs to generate a smaller bias compensation current, thereby improving the working efficiency. Description of the Drawings

[0050] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0051] Figure 1 is a schematic structural diagram of a power amplifier circuit in an embodiment of the present invention Figure 1 ;

[0052] Figure 2 is a schematic structural diagram of a power amplifier circuit in an embodiment of the present invention Figure 2 ;

[0053] Figure 3 is a schematic structural diagram of a power amplifier circuit in an embodiment of the present invention Figure 3 ;

[0054] Figure 4 is a schematic circuit diagram of the temperature detection unit 131 in an embodiment of the present invention;

[0055] Figure 5 is a schematic structural diagram of the first circuit board 21 in an embodiment of the present invention;

[0056] Figure 6 is a schematic structural diagram of a power amplifier circuit in an embodiment of the present invention Figure 4 ;

[0057] Figure 7 is a schematic circuit diagram of the compensation control unit 132 in an embodiment of the present invention;

[0058] Figure 8 is a schematic circuit diagram of the power amplifier circuit in an embodiment of the present invention;

[0059] Figure 9 is a schematic structural diagram of the first circuit board 21 and the second circuit board 22 in an embodiment of the present invention;

[0060] Figure 10 is a waveform schematic diagram of some key devices or key nodes in an embodiment of the present invention.

[0061] Description of the reference numerals:

[0062] 11 - Driver stage module; 12 - Output stage module; 13 - Bias compensation module; 14 - First bias module; 15 - Second bias module; 16 - Output matching module;

[0063] IN - Original input signal; PA_EN control signal; ANT - Antenna;

[0064] 131 - Temperature detection unit; 132 - Compensation control unit;

[0065] 1311 - First temperature sensitive device; 1312 - Second temperature sensitive device; U1 - Subtractor;

[0066] R1 - First resistor; R2 - Second resistor; D1 - First diode; D2 - Second diode;

[0067] U2 - Analog - to - digital converter; U3 - Controller; 1321 - Current source sub - unit;

[0068] I - Current source; K - Switch; Iboost - Bias compensation current;

[0069] IREF1 - First bias current source; Q14 - First bias diode; IREF2 - Second bias current source; Q15 - Second bias diode;

[0070] Q11 - Drive diode; L11 - Drive inductor; Q12 - Output diode; L12 - Output inductor;

[0071] C1 - First capacitor; C2 Second capacitor; C16 - Matching capacitor; L16 - Matching inductor;

[0072] Vcc1 - First power supply; Vcc2 - Second power supply; Vcc3 - Third power supply; Vcc4 - Fourth power supply. Detailed implementation mode

[0073] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the protection scope of the present invention.

[0074] The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of the present invention and the above - mentioned drawings are used to distinguish similar objects and do not necessarily need to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present invention described here can be implemented in an order other than those illustrated or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non - exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0075] The technical solution of the present invention will be described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments.

[0076] Please refer to Figure 1 , in an embodiment of the present invention, the power amplifier circuit includes a driver stage module 11, an output stage module 12, a first bias module 14, a second bias module 15, and a bias compensation module 13;

[0077] The bias compensation module 13 is configured to be able to monitor the temperature of the output stage module 12 to obtain the output stage temperature; the bias compensation module 13 is also configured to be able to monitor the temperature of the environment where the power amplifier is located to obtain the ambient temperature;

[0078] The bias compensation module 13 accesses the control signal PA_EN, and the bias compensation module 13 is electrically connected to the input end of the first bias module 14 for: when the duty cycle of the control signal PA_EN changes, generating a bias compensation current Iboost according to the output stage temperature and the ambient temperature, and feeding back the bias compensation current Iboost to the first bias module 14; the control signal PA_EN includes a first control signal PA_EN1 and a second control signal PA_EN2;

[0079] Among them, the control signal PA_EN can be understood as an enable signal for controlling the on and off of the amplifier circuit. For example, when the control signal PA_EN is at a high level, the power amplifier circuit is turned on, and when the control signal PA_EN is at a low level, the power amplifier circuit is turned off;

[0080] The change in the duty cycle of the control signal PA_EN can be understood as the switching between two control signals with different duty cycles, and the waveform can be, for example Figure 10 the waveforms of the two control signals in.

[0081] The first bias module 14 accesses the control signal, and the first bias module 14 is electrically connected to the driver stage module 11 to feed back the first bias voltage to the driver stage module 11 according to the bias compensation current Iboost when the control signal is the first level signal;

[0082] The second bias module 15 accesses the control signal, and the second bias module 15 is electrically connected to the output stage module 12 to feed back the second bias voltage to the output stage module 12 when the control signal is the first level signal;

[0083] The first end of the driving stage module 11 is connected to the original input signal IN, and the second end of the driving stage module 11 is electrically connected to the first end of the output stage module 12. Based on the first bias voltage, the original input signal IN is amplified to obtain an amplified signal, and the amplified signal is transmitted to the output stage module 12;

[0084] The second end of the output stage module 12 is directly or indirectly electrically connected to the antenna ANT. Based on the second bias voltage, the received amplified signal is amplified to obtain a target signal, and the target signal is directly or indirectly transmitted to the antenna ANT.

[0085] In the above embodiments, the bias compensation for the first bias module is completed at the moment when the rising edge of the control signal arrives when the working mode of the power amplifier circuit changes, and the bias compensation current does not change during the entire working process of the power amplifier circuit. This ensures the stability of the working point during the working process of the power amplifier circuit and does not generate a serious memory effect.

[0086] In an example, the working principle of the power amplifier is as follows:

[0087] The duty cycle of the first control signal PA_EN1 is 90%, and the duty cycle of the second control signal PA_EN2 is 10%. When the control signal switches from the second control signal to the first control signal within a short period of time, the temperature of the output stage module 12 will be higher. When the rising edge of the first control signal arrives, the bias compensation module 13 monitors the output stage temperature and the ambient temperature. According to the temperature monitoring results, a bias compensation current Iboost is generated and fed back to the first bias module 14. The first bias module 14 generates a first bias voltage based on the received bias compensation current and the first control signal, and feeds it back to the driving stage module 11, so that the driving stage module 11 amplifies the original input signal IN based on the first bias voltage.

[0088] In the above power amplifier circuit, the bias compensation module 13 monitors the output stage temperature of the output stage module 12 and the ambient temperature of the power amplifier. Then, when the duty cycle of the control signal PA_EN changes (i.e., switches between the first control signal PA_EN1 and the second control signal PA_EN2), the bias compensation module generates a bias compensation current Iboost to compensate the first bias voltage, so as to compensate for the decrease in gain caused by the excessive temperature of the output stage module 12 through the increase in the first bias voltage of the driving stage module 11, so that the gain tends to be consistent when the power amplifier circuit switches the working mode;

[0089] Meanwhile, the bias compensation module 13 compensates the first bias voltage of the first bias module 14. Compared with some solutions where the bias compensation module 13 compensates the second bias voltage of the second bias module 15, the bias compensation current Iboost that needs to be generated in the present invention is smaller, thereby improving the working efficiency.

[0090] Please refer to Figure 2 , in an embodiment, the bias compensation module 13 includes a temperature difference detection unit 131 and a compensation control unit 132;

[0091] The temperature difference detection unit 131 is configured to monitor the output stage temperature and the ambient temperature to generate a temperature difference signal according to the output stage temperature and the ambient temperature, and the temperature difference signal characterizes the temperature difference between the output stage temperature and the ambient temperature;

[0092] The output end of the temperature difference detection unit 131 is electrically connected to the first input end of the compensation control unit 132 to transmit the temperature difference signal to the compensation control unit 132;

[0093] The second input end of the compensation control unit 132 accesses a control signal PA_EN, and the output end of the compensation control unit 132 is electrically connected to the input end of the first bias module 14. When the duty cycle of the control signal PA_EN changes (i.e., switches between the first control signal PA_EN1 and the second control signal PA_EN2), a bias compensation current boost is generated according to the temperature difference signal and the bias compensation current Iboost is fed back to the first bias module.

[0094] Please refer to Figure 3 , in an embodiment, the temperature difference detection unit 131 includes a first temperature sensitive element 1311, a second temperature sensitive element 1312 and a subtractor U1,

[0095] The voltage value or resistance value of the first temperature sensitive element 1311 is adapted to the output stage temperature. The first end of the first temperature sensitive element 1311 is electrically connected to the first input end of the subtractor U1, and the second end of the first temperature sensitive element 1311 is grounded;

[0096] The voltage value or resistance value of the second temperature sensitive element 1312 is adapted to the ambient temperature. The first end of the second temperature sensitive element 1312 is electrically connected to the second input end of the subtractor U1, and the second end of the second temperature sensitive element 1312 is grounded;

[0097] The output end of the subtractor U1 is electrically connected to the first input end of the compensation control unit 132.

[0098] In the above embodiments, the voltage value or resistance value of the first temperature-sensitive element 1311 is adapted to the output stage temperature. It can be understood that the first temperature-sensitive element is thermally coupled to the output stage module, so that the voltage value or resistance value of the first temperature-sensitive element changes with the change of the output stage temperature; the voltage value or resistance value of the second temperature-sensitive element 1312 is adapted to the ambient temperature. It can be understood that the second temperature-sensitive element is placed at a position far from the output stage module (for example Figure 5 the position in), so that the voltage value or resistance value of the second temperature-sensitive element changes with the change of the ambient temperature of the environment where the power amplifier circuit is located.

[0099] In the above embodiments, the output stage temperature and the ambient temperature are converted into voltage quantities that are convenient to be reflected in the circuit through the temperature-sensitive elements, so that the first bias voltage changes with the change of the ambient difference signal, thereby reducing the change of the gain of the power amplifier circuit when switching the working mode.

[0100] Please refer to Figure 4 , in one embodiment, the temperature difference detection unit 132 further includes a first resistor R1 and a second resistor R2. The first temperature-sensitive element 1311 is a first diode D1, and the second temperature-sensitive element 1312 is a second diode D2.

[0101] The voltage value of the first diode D1 (i.e., the forward voltage drop of the first diode) is adapted to the output stage temperature. The positive electrode of the first diode D1 is electrically connected to the first end of the first resistor R1 and the first input terminal of the subtractor U1, and the negative electrode of the first diode D1 is grounded;

[0102] The voltage value of the second diode D2 (i.e., the forward voltage drop of the second diode) is adapted to the ambient temperature. The positive electrode of the second diode D2 is electrically connected to the first end of the second resistor R2 and the second input terminal of the subtractor U1, and the negative electrode of the second diode D2 is grounded;

[0103] The second end of the first resistor R1 and the second end of the second resistor R2 are electrically connected to the first power supply Vcc1;

[0104] The first diode and the second diode therein are temperature-sensitive diodes.

[0105] In the above embodiments, the first diode and the second diode can be replaced by other temperature-sensitive devices. For example, they can be replaced by temperature-sensitive resistors, and then the resistance values of the temperature-sensitive resistors are respectively adapted to the output stage temperature and the ambient temperature; for example, they can also be replaced by HBTs, and then the threshold voltages of the HBTs are respectively adapted to the output stage temperature and the ambient temperature.

[0106] Please refer to Figure 5, In one implementation, some modules of the power amplifier circuit are integrated on the first circuit board 21. The output stage module includes an output stage HBT array, and the driver stage module includes a driver stage HBT array. The first diode D1 can be disposed between the output stage HBT arrays to form a temperature tight coupling with the HBT arrays of the output stage module. The second diode D2 can be disposed at any position far from the output stage HBT arrays, such as Figure 5 at the upper left corner of the first circuit board 21 in Figure 5 . The first diode D1 monitors the temperature of the output stage HBT array and converts it into a first temperature voltage with a voltage value of V1. The second diode D2 monitors the ambient temperature and converts it into a second temperature voltage with a voltage value of V2. V1 and V2 pass through a subtractor and are converted into a temperature difference signal.

[0107] Please refer to Figure 6 , In one implementation, the compensation control unit 132 includes an analog-to-digital converter U2, a controller U3, and a current source sub-unit 1321;

[0108] The input end of the analog-to-digital converter U2 is electrically connected to the output end of the temperature difference detection unit 131, and the enable end of the analog-to-digital converter U2 is connected to the control signal PA_EN. When the duty cycle of the control signal PA_EN changes (i.e., switches between the first control signal PA_EN1 and the second control signal PA_EN2), the temperature difference signal is subjected to analog-to-digital conversion to obtain a digital temperature difference signal;

[0109] The output end of the analog-to-digital converter U2 is electrically connected to the input end of the controller U3 to transmit the digital temperature difference signal to the controller U3;

[0110] The output end of the controller U3 is electrically connected to the input end of the current source sub-unit 1321 to control the current source sub-unit 1321 to generate a bias compensation current Iboost according to the digital temperature difference signal. The controller U3 herein can be a control chip or a control circuit integrated by multiple electronic devices, thereby realizing controlling the current source sub-unit 1321 to generate the bias compensation current Iboost according to the received digital temperature difference signal;

[0111] The output end of the current source sub-unit 1321 is electrically connected to the input end of the first bias module 14 to feedback the bias compensation current Iboost to the first bias module 14.

[0112] In an example, the input end of the analog-to-digital converter U2 is electrically connected to the output end of the subtractor U1 to receive the temperature difference signal.

[0113] Please refer to Figure 7In one embodiment, the current source sub-unit 1321 includes M current sources I and M switches K. The first end of each switch is electrically connected to the output end of the controller U3, the second end of each switch is electrically connected to the first end of a current source, and the second end of each current source is electrically connected to the input end of the first bias module 14. The controller U3 controls the number of closed switches among the M switches K according to the digital temperature difference signal to control the magnitude of the bias compensation current Iboost.

[0114] In an example, the specific working process of the compensation control module 132 is as follows:

[0115] The analog-to-digital converter U2 receives the temperature difference signal from the subtractor U1, converts the temperature difference signal through analog-to-digital conversion into an n-bit data (i.e., the numerical temperature difference signal) and transmits it to the controller U3. The controller U3 generates a corresponding control signal according to the received n-bit data to control the number of closed switches among the M switches, so as to control the magnitude of the bias compensation current Iboost. The larger the voltage value Vcon corresponding to the temperature difference signal, the more the number of closed switches, and the larger the bias compensation current Iboost.

[0116] Please refer to Figure 8 In one embodiment, the first bias module 14 includes a first bias transistor Q14 and a first bias current source IREF1.

[0117] The first end of the first bias current source IREF1 is electrically connected to the second power supply Vcc2, the controlled end of the first bias current source IREF1 accesses the control signal PA_EN, and the second end of the first bias current source IREF1 is electrically connected to the control electrode of the first bias transistor Q14.

[0118] The control electrode of the first bias transistor Q14 is electrically connected to the output end of the bias compensation module 13.

[0119] The first pole of the first bias transistor Q14 is electrically connected to the third power supply Vcc3, and the second pole of the first bias transistor Q14 is electrically connected to the first end of the driver stage module 11.

[0120] In one embodiment, the second bias module 15 includes a second bias transistor Q15 and a second bias current source IREF2.

[0121] The first end of the second bias current source IREF2 is electrically connected to the fourth power supply Vcc4, the controlled end of the second bias current source IREF2 accesses the control signal PA_EN, and the second end of the second bias current source IREF2 is electrically connected to the control electrode of the second bias transistor Q15.

[0122] The first pole of the second bias transistor Q15 is electrically connected to the third power supply Vcc3, and the second pole of the second bias transistor Q15 is electrically connected to the first end of the output stage module 12.

[0123] In one embodiment, the driver stage module 11 includes a driver transistor Q11. The control pole of the driver transistor Q11 is electrically connected to the output end of the first bias module 14. The first pole of the driver transistor Q11 is directly or indirectly electrically connected to the third power supply Vcc3, and the second pole of the driver transistor Q11 is grounded.

[0124] The driver transistor Q11 therein can be a single GaAs HBT or an array composed of GaAs HBTs. The control pole of the driver transistor Q11 can be the base of the driver transistor Q11. The first pole of the driver transistor Q11 can be the collector of the driver transistor Q11, and the second pole of the driver transistor Q11 can be the emitter of the driver transistor Q11.

[0125] In one embodiment, the driver stage module 11 includes a driver inductor L11. The first end of the driver inductor L11 is electrically connected to the first pole of the driver transistor Q11, and the second end of the driver inductor L11 is electrically connected to the third power supply Vcc3.

[0126] In one embodiment, the output stage module 12 includes an output transistor Q12. The control pole of the output transistor Q12 is electrically connected to the output end of the second bias module 15. The first pole of the output transistor Q12 is directly or indirectly electrically connected to the third power supply Vcc3, and the second pole of the output transistor Q12 is grounded.

[0127] The output transistor Q12 therein can be a single GaAs HBT or an array composed of GaAs HBTs. The control pole of the output transistor Q12 can be the base of the output transistor Q12. The first pole of the output transistor Q12 can be the collector of the output transistor Q12, and the second pole of the output transistor Q12 can be the emitter of the output transistor Q12.

[0128] In one embodiment, the output stage module 12 includes an output inductor L12. The first end of the output inductor L12 is electrically connected to the first pole of the output transistor Q12, and the second end of the output inductor L12 is electrically connected to the third power supply Vcc3.

[0129] In one embodiment, the power amplifier circuit further includes a first capacitor C1 and a second capacitor C2.

[0130] The first end of the first capacitor C1 is connected to the original input signal IN, and the second end of the first capacitor C1 is electrically connected to the first end of the driver stage module 11.

[0131] The first end of the second capacitor C2 is electrically connected to the second end of the driving stage module 11, and the second end of the second capacitor C2 is electrically connected to the first end of the output stage module 12.

[0132] The function of the first capacitor C1 is to isolate the power amplifier circuit from the pre-stage signal transmitting circuit, and the function of the second capacitor C2 is to isolate the driving stage module from the output stage module.

[0133] In one embodiment, the power amplifier circuit further includes an output matching module 16. The first end of the output matching module 16 is electrically connected to the second end of the output stage module 12, and the second end of the output matching module 16 is electrically connected to the antenna ANT.

[0134] In one example, the output matching module 16 includes a matching capacitor C16 and a matching inductor L16. The first end of the matching capacitor C16 is electrically connected to the first pole of the output stage transistor Q12, and the second end of the matching capacitor C16 is electrically connected to the antenna ANT;

[0135] The first end of the matching inductor L16 is electrically connected to the second end of the matching capacitor C16, and the second end of the matching inductor L16 is grounded.

[0136] In another example, the output matching module 16 can be a matching network composed of multiple matching units. Each matching unit includes a matching capacitor and a matching inductor. The first end of each matching inductor is electrically connected to one end of a matching capacitor, and the second end of each matching inductor is grounded. Then, multiple matching capacitors are connected in series to form a matching network.

[0137] Please refer to Figure 9 In one embodiment, the driving stage module 11, the output stage module 12, the first bias module 14, and the second bias module 15 are disposed on the first circuit board 21, and a part of the bias compensation module 13 is disposed on the second circuit board 22.

[0138] In one example, since the GaAs HBT process is not suitable for making complex digital circuits, functions such as realizing analog-to-digital conversion and controlling the bias compensation current can be implemented based on silicon-based processes such as CMOS, SOI, and SiGe, as Figure 10 shown. Temperature detection diodes (the first diode and the second diode) are placed on the first circuit board 21. The first diode D1 monitors the voltage value V1 generated by the output stage module, and the second diode D2 monitors the voltage value V2 generated by the ambient temperature. They are transmitted to the second circuit board 22 through bonding wires. After being processed by the circuit on the second circuit board 22, the bias compensation current Iboost is returned to the first circuit board 21.

[0139] To more clearly illustrate the positive effects of the present invention, the following describes Figure 10 an embodiment of the present invention:

[0140] In this embodiment, the driving transistor Q11 and the output transistor Q12 are HBTs;

[0141] Figure 10 The dotted waveform corresponding to PA_EN1 is the waveform corresponding to the first control signal; the solid waveform corresponding to PA_EN2 is the waveform corresponding to the second control signal; the dotted waveform corresponding to T1 is the curve of the junction temperature of the output transistor Q12 changing with time when the waveform of the control signal is the dotted waveform corresponding to PA_EN1; the solid waveform corresponding to T2 is the curve of the junction temperature of the output transistor Q12 changing with time when the waveform of the control signal is the solid waveform corresponding to PA_EN2;

[0142] The dotted waveform corresponding to Gn1 is the gain of the power amplifier circuit when there is no bias compensation module and when the waveform of the control signal is the dotted waveform corresponding to PA_EN1;

[0143] The solid waveform corresponding to Gn2 is the gain of the power amplifier circuit when there is no bias compensation module and when the waveform of the control signal is the solid waveform corresponding to PA_EN2;

[0144] The dotted waveform corresponding to Gy1 is the gain of the power amplifier circuit when there is a bias compensation module and when the waveform of the control signal is the dotted waveform corresponding to PA_EN1;

[0145] The solid waveform corresponding to Gy2 is the gain of the power amplifier circuit when there is a bias compensation module and when the waveform of the control signal is the solid waveform corresponding to PA_EN2.

[0146] From Figure 10 Gn1, Gn2, Gy1, and Gy2 in, it can be seen that when the power amplifier circuit does not include the bias compensation module 13, when switching from the second control signal to the first control signal, the gain drops significantly, while when the power amplifier circuit includes the bias compensation module 13, when switching from the second control signal to the first control signal, the gain tends to be consistent;

[0147] The reason for the above changes is that in the traditional power amplifier circuit, at two duty cycles of 10% (the second control signal) and 90% (the first control signal), the gain can have a difference of more than 1 dB. The decrease in gain will lead to a decrease in output power, thereby affecting the communication rate of the system. Moreover, the above change in gain is caused by the change in the junction temperature of the output transistor and the driving transistor. Therefore, adding a bias compensation module to compensate the bias current of the driving transistor can reduce the above changes.

[0148] The present invention further provides an electronic device, including the DEVM compensation circuit for a power amplifier or the power amplifier involved in the foregoing.

[0149] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than limiting them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A power amplifier circuit, characterized in that, It includes a driver stage module, an output stage module, a first bias module, a second bias module, and a bias compensation module; The bias compensation module is configured to be able to monitor the temperature of the output stage module to obtain the output stage temperature; The bias compensation module is further configured to be able to monitor the temperature of the environment where the power amplifier is located to obtain the ambient temperature; The bias compensation module accesses a control signal, and the bias compensation module is electrically connected to the input end of the first bias module for: when the duty cycle of the control signal changes, generating a bias compensation current according to the output stage temperature and the ambient temperature, and feeding back the bias compensation current to the first bias module; The duty cycle is a duty cycle control signal for switching between a first level signal and a second level signal in the control signal; The first bias module accesses the control signal, and the first bias module is electrically connected to the driver stage module to feed back a first bias voltage to the driver stage module according to the bias compensation current when the control signal is the first level signal; The second bias module accesses the control signal, and the second bias module is electrically connected to the output stage module to feed back a second bias voltage to the output stage module when the control signal is the first level signal; The first end of the driver stage module accesses an original input signal, and the second end of the driver stage module is electrically connected to the first end of the output stage module to amplify the original input signal based on the first bias voltage to obtain an amplified signal, and transmit the amplified signal to the output stage module; The second end of the output stage module is directly or indirectly electrically connected to an antenna to amplify the received amplified signal based on the second bias voltage to obtain a target signal, and directly or indirectly transmit the target signal to the antenna; The first bias module includes a first bias transistor and a first bias current source; The first end of the first bias current source is electrically connected to a second power supply, the controlled end of the first bias current source accesses the control signal, and the second end of the first bias current source is electrically connected to the control electrode of the first bias transistor; The control electrode of the first bias transistor is electrically connected to the output end of the bias compensation module; The first electrode of the first bias transistor is electrically connected to a third power supply, and the second electrode of the first bias transistor is electrically connected to the first end of the driver stage module; The driver stage module includes a driver transistor, the control electrode of the driver transistor is electrically connected to the output end of the first bias module, the first electrode of the driver transistor is directly or indirectly electrically connected to a third power supply, the second electrode of the driver transistor is grounded, and the driver transistor is a single GaAs HBT or an array composed of GaAs HBTs.

2. The power amplifier circuit according to claim 1, wherein The bias compensation module includes a temperature difference detection unit and a compensation control unit; The temperature difference detection unit is configured to be able to monitor the output stage temperature and the ambient temperature to generate a temperature difference signal according to the output stage temperature and the ambient temperature, and the temperature difference signal characterizes the temperature difference between the output stage temperature and the ambient temperature; The output end of the temperature difference detection unit is electrically connected to the first input end of the compensation control unit to transmit the temperature difference signal to the compensation control unit; The second input end of the compensation control unit accesses the control signal, and the output end of the compensation control unit is electrically connected to the input end of the first bias module. When the duty cycle of the control signal changes, a bias compensation current is generated according to the temperature difference signal, and the bias compensation current is fed back to the first bias module.

3. The power amplifier circuit according to claim 2, wherein The temperature difference detection unit includes a first temperature sensitive element, a second temperature sensitive element and a subtractor; The voltage value or resistance value of the first temperature sensitive element is adapted to the output stage temperature. The first end of the first temperature sensitive element is electrically connected to the first input end of the subtractor, and the second end of the first temperature sensitive element is grounded; The voltage value or resistance value of the second temperature sensitive element is adapted to the ambient temperature. The first end of the second temperature sensitive element is electrically connected to the second input end of the subtractor, and the second end of the second temperature sensitive element is grounded; The output end of the subtractor is electrically connected to the first input end of the compensation control unit.

4. The power amplifier circuit according to claim 3, characterized in that, The temperature difference detection unit further includes a first resistor and a second resistor. The first temperature sensitive element is a first diode, and the second temperature sensitive element is a second diode; The voltage value of the first diode is adapted to the output stage temperature. The positive electrode of the first diode is electrically connected to the first end of the first resistor and the first input end of the subtractor, and the negative electrode of the first diode is grounded; The voltage value of the second diode is adapted to the ambient temperature. The positive electrode of the second diode is electrically connected to the first end of the second resistor and the second input end of the subtractor, and the negative electrode of the second diode is grounded; The second ends of the first resistor and the second resistor are electrically connected to a first power supply.

5. The power amplifier circuit according to claim 2, characterized in that, The compensation control unit includes an analog-to-digital converter, a controller and a current source sub-unit; The input end of the analog-to-digital converter is electrically connected to the output end of the temperature difference detection unit, and the enable end of the analog-to-digital converter accesses the control signal. When the duty cycle of the control signal changes, the temperature difference signal is subjected to analog-to-digital conversion to obtain a digital temperature difference signal; The output end of the analog-to-digital converter is electrically connected to the input end of the controller to transmit the digital temperature difference signal to the controller; The output end of the controller is electrically connected to the input end of the current source sub-unit to control the current source sub-unit to generate a bias compensation current according to the digital temperature difference signal; The output end of the current source sub-unit is electrically connected to the input end of the first bias module to feed back the bias compensation current to the first bias module.

6. The power amplifier circuit according to claim 5, characterized in that The current source sub-unit includes M current sources and M switches. The first end of each switch is electrically connected to the output end of the controller, the second end of each switch is electrically connected to the first end of a current source, and the second end of each current source is electrically connected to the input end of the first bias module. The controller controls the number of closed switches among the M switches according to the digital temperature difference signal to control the magnitude of the bias compensation current.

7. The power amplifier circuit according to claim 1, characterized in that, The second bias module includes a second bias transistor and a second bias current source. The first end of the second bias current source is electrically connected to a fourth power supply, the controlled end of the second bias current source receives the control signal, and the second end of the second bias current source is electrically connected to the control electrode of the second bias transistor. The first pole of the second bias transistor is electrically connected to a third power supply, and the second pole of the second bias transistor is electrically connected to the first end of the output stage module.

8. The power amplifier circuit according to claim 1, wherein The driver stage module includes a drive inductor. The first end of the drive inductor is electrically connected to the first pole of the drive transistor, and the second end of the drive inductor is electrically connected to the third power supply.

9. The power amplifier circuit according to claim 1, wherein The output stage module includes an output transistor. The control electrode of the output transistor is electrically connected to the output end of the second bias module. The first pole of the output transistor is directly or indirectly electrically connected to the third power supply, and the second pole of the output transistor is grounded.

10. The power amplifier circuit according to claim 9, wherein, The output stage module includes an output inductor. The first end of the output inductor is electrically connected to the first pole of the output transistor, and the second end of the output inductor is electrically connected to the third power supply.

11. The power amplifier circuit according to claim 1, characterized in that, It further includes a first capacitor and a second capacitor. The first end of the first capacitor receives the original input signal, and the second end of the first capacitor is electrically connected to the first end of the driver stage module. The first end of the second capacitor is electrically connected to the second end of the driver stage module, and the second end of the second capacitor is electrically connected to the first end of the output stage module.

12. The power amplifier circuit according to claim 1, characterized in that, It further includes an output matching module. The first end of the output matching module is electrically connected to the second end of the output stage module, and the second end of the output matching module is electrically connected to the antenna.

13. The power amplifier circuit according to claim 1, wherein The driver stage module, the output stage module, the first bias module, and the second bias module are disposed on a first circuit board, and a part of the bias compensation module is disposed on a second circuit board.

14. An electronic device, characterized in that, It includes the power amplifier circuit according to any one of claims 1 to 13.

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