A fast-switching radio frequency switch circuit, chip and electronic device thereof

Abstract

The present invention discloses a radio frequency switch circuit, a chip and an electronic device thereof with fast switching. The radio frequency switch circuit includes a series switch branch and a parallel switch branch of at least one transmitting path, and a series switch branch and a parallel switch branch of at least one receiving path. Among them, both ends of the series switch branch in the transmitting path are respectively connected to the transmitting end and the antenna end, and both ends of the parallel switch branch are respectively connected to the transmitting end and the ground potential end; both ends of the series switch branch in the receiving path are respectively connected to the receiving end and the antenna end, and both ends of the parallel switch branch are respectively connected to the receiving end and the ground potential end. Through optimized structural design, the radio frequency switch circuit realizes fast switching of the working mode of the radio frequency front-end system under the condition of ensuring performance indexes such as power handling capacity and linearity and without increasing the cost, and improves the transmission rate of the communication system.

Description

Technical Field

[0001] The present invention relates to a radio frequency (RF) switch circuit with fast switching, and also relates to an integrated circuit chip and a corresponding electronic device including the RF switch circuit, belonging to the technical field of RF integrated circuits. Background Art

[0002] In a wireless communication system, as one of the key modules in the RF front-end circuit, the RF switch is used to accurately and synchronously switch the transmission path of RF signals, select the corresponding RF signal path, and realize the reception and transmission of RF signals when the system shares an antenna.

[0003] With the continuous development of RF integrated circuit technology and the trend of diversified application scenarios of communication terminals, the RF front-end system of mobile communication terminals needs to support an increasing number of operating modes and frequency bands, and the requirements for the performance indicators of RF switches are also getting higher and higher. In addition to power handling capacity, isolation, linearity, and insertion loss, the switching time of the RF switch is also a very important performance indicator, which directly affects the transmission rate of the communication system.

[0004] In the prior art, there are usually three structural schemes for RF switch circuits, namely series-parallel type RF switches, relative negative voltage type RF switches, and constant negative voltage type RF switches.

[0005] The series-parallel type RF switch circuit is as Figure 1 shown. Each series-parallel switch branch is composed of switch transistors in a stacked structure. Among them, the gate voltage of the switch transistors in each conducting branch is 2.5V, and the gate voltage of the switch transistors in each non-conducting branch is 0V. The RF switch circuit of this scheme has a simple structure, a relatively small chip area, and a small switching time for the transceiver link. However, the disadvantage of this scheme is that as the number of stacked switch transistors increases, the linearity of the RF switch becomes poor.

[0006] The relative negative voltage type RF switch circuit is as Figure 2 shown. Each series-parallel switch branch is composed of switch transistors in a stacked structure in series with capacitors. Among them, the gate of each switch transistor in the conducting branch is biased at a high potential and the source is biased at a low potential, and its gate-source voltage is greater than the threshold voltage to turn on the switch; the gate of each switch transistor in the non-conducting branch is biased at a low potential and the source is biased at a high potential, and its gate-source voltage is a negative voltage to turn off the switch. The RF switch circuit of this scheme has a relatively simple structure and good linearity. However, the disadvantages of this scheme are that the chip area is large and the switching time of the transceiver link is large.

[0007] In a constant negative voltage type RF switch circuit, the gate and body regions of the switching transistors in each turn-off branch are biased at a constant negative voltage, which is generated by a charge pump driven by a fully differential ring oscillator. The linearity of the constant negative voltage type RF switch circuit is greatly improved, and at the same time, the switching time of the transceiver link is small. However, the disadvantages of this solution are relatively complex structure, large power consumption, and obvious increase in cost.

[0008] Therefore, how to reduce the switching time of the RF switch and improve the transmission rate of the communication system while ensuring performance indicators such as power handling capacity, isolation, and linearity and without increasing the cost has always been a very important technical research topic in this field. In a Chinese patent application with publication number CN113541663 A, a RF switch switching control circuit is disclosed. The circuit includes an edge detection delay circuit for generating a high level of the output delay pulse signal at the rising or falling edge of the power supply voltage signal and the RF switching control input signal; a voltage stabilizing circuit for stabilizing the power supply voltage signal, performing a boosting adjustment through the delay pulse signal, and outputting a stable boosted power supply signal; an oscillation circuit for outputting an oscillation signal with a corresponding frequency and amplitude; the oscillation signal includes a first oscillation signal corresponding to the high level period of the delay pulse signal and a second oscillation signal corresponding to the low level interval of the delay pulse signal, and the frequency and amplitude of the first oscillation signal are greater than those of the second oscillation signal; a negative charge pump circuit configured to be able to achieve rapid establishment of a negative voltage and increase the negative voltage output. This circuit can achieve rapid switching of the RF switch through the rapid charge and discharge of the negative charge pump circuit. Summary of the Invention

[0009] The primary technical problem to be solved by the present invention is to provide a rapidly switching RF switch circuit.

[0010] Another technical problem to be solved by the present invention is to provide an integrated circuit chip and a corresponding electronic device including the RF switch circuit.

[0011] To achieve the above object, the present invention adopts the following technical solutions:

[0012] According to the first aspect of the embodiments of the present invention, a rapidly switching RF switch circuit is provided, including a series switch branch and a parallel switch branch of at least one transmission path, and a series switch branch and a parallel switch branch of at least one reception path; wherein,

[0013] In the transmission path, two ends of the series switch branch are respectively connected to a transmitting end and an antenna end, and two ends of the parallel switch branch are respectively connected to the transmitting end and a ground potential end;

[0014] In the receiving path, both ends of the series switch branch are respectively connected to the receiving end and the antenna end, and both ends of the parallel switch branch are respectively connected to the receiving end and the ground potential end.

[0015] When the transmitting path or the receiving path is in the working state, the series switch branch in this path is closed and the parallel switch branch is opened;

[0016] When the transmitting path or the receiving path is in the non - working state, the series switch branch in this path is opened and the parallel switch branch is closed.

[0017] Preferably, both the series switch branch and the parallel switch branch adopt a switch transistor stacking structure, which is composed of multiple switch transistors connected in series by source - drain electrodes in sequence;

[0018] The body terminal of each switch transistor is connected to the ground potential end through a body - terminal bias resistor, the drain and source are respectively connected to the ground potential end through a drain - bias resistor and a source - bias resistor, and the gate is connected to the bias voltage through a gate - bias resistor.

[0019] Preferably, when the RF switch is in the transmitting working mode,

[0020] For the series switch branch of the transmitting path in the working state and the parallel switch branch of the receiving path, the gate - bias voltage of the switch transistor is a positive voltage;

[0021] For the parallel switch branch of the transmitting path in the working state and the series switch branch of the receiving path, and the series switch branch of the transmitting path not in the working state, the gate - bias voltage of the switch transistor is the ground potential.

[0022] Preferably, when the RF switch is in the receiving working mode,

[0023] For the series switch branch of the receiving path in the working state and the parallel switch branch of the transmitting path, the gate - bias voltage of the switch transistor is a positive voltage;

[0024] For the parallel switch branch of the receiving path in the working state and the series switch branch of the transmitting path, and the series switch branch of the receiving path not in the working state, the gate - bias voltage of the switch transistor is the ground potential.

[0025] Preferably, at one end of the series switch branch of the receiving path connected to the receiving end, a first parallel capacitor is added, and both ends of this parallel capacitor are respectively connected to the gate and source of the switch transistor, which is used to improve the linearity of the RF switch.

[0026] Preferably, a first parallel capacitor and a second parallel capacitor are respectively added to both ends of the series switch branch of the receiving path. The two ends of the first parallel capacitor are respectively connected to the gate and source of the switching transistor on the receiving end side, and the two ends of the second parallel capacitor are respectively connected to the gate and drain of the switching transistor on the antenna end side, so as to improve the linearity of the RF switch.

[0027] Preferably, a third parallel capacitor is added to one end of the parallel switch branch of the transmitting path that is connected to the ground potential terminal. The two ends of this parallel capacitor are respectively connected to the gate and source of the switching transistor, so as to improve the linearity of the RF switch.

[0028] Preferably, a third parallel capacitor and a fourth parallel capacitor are respectively added to both ends of the parallel switch branch of the transmitting path. The two ends of the third parallel capacitor are respectively connected to the gate and source of the switching transistor on the ground potential terminal side, and the two ends of the fourth parallel capacitor are respectively connected to the gate and drain of the switching transistor on the transmitting end side, so as to improve the linearity of the RF switch.

[0029] According to the second aspect of the embodiments of the present invention, an integrated circuit chip is provided, and the integrated circuit chip includes the above-mentioned RF switch circuit.

[0030] According to the third aspect of the embodiments of the present invention, an electronic device is provided, and the electronic device includes the above-mentioned RF switch circuit. Compared with the prior art, the fast-switching RF switch circuit, chip and its electronic device provided by the present invention realize the fast switching of the working mode of the RF front-end system through the optimized design of the RF switch circuit, while ensuring performance indicators such as power handling ability and linearity and without increasing the cost, and improve the transmission rate of the communication system. Therefore, the fast-switching RF switch circuit provided by the present invention has the beneficial effects of ingenious and reasonable design, simple structure, low cost, small switching time and high linearity. Description of the Drawings

[0031] Figure 1 is the schematic diagram of the series-parallel RF switch circuit in the prior art;

[0032] Figure 2 is the schematic diagram of the relative negative pressure type RF switch circuit in the prior art;

[0033] Figure 3 is the schematic diagram of the architecture of a RF front-end module in the Wi-Fi system in the prior art;

[0034] Figure 4In the embodiment of the present invention, it is the circuit schematic diagram of the fast-switching RF switch in the transmitting operating mode;

[0035] Figure 5 In the embodiment of the present invention, it is the circuit schematic diagram of the fast-switching RF switch in the receiving operating mode;

[0036] Figure 6 In the embodiment of the present invention, it is the circuit schematic diagram of the technical solution for improving the linearity of the RF switch;

[0037] Figure 7 In the embodiment of the present invention, it is the circuit schematic diagram of another technical solution for improving the linearity of the RF switch;

[0038] Figure 8 In the prior art, it is the simulation test diagram of the circuit switching time of the relative negative pressure type RF switch;

[0039] Figure 9 In the embodiment of the present invention, it is the simulation test diagram of the circuit switching time of the fast-switching RF switch;

[0040] Figure 10 It is the schematic diagram of the electronic device adopting the RF switch circuit provided by the present invention. Detailed Embodiment

[0041] The following further elaborates on the technical solution of the present invention in detail in conjunction with the accompanying drawings and specific embodiments.

[0042] For the convenience of understanding and illustration, the present invention first briefly introduces the conceptual connotation of the switching time of the RF switch, and on this basis, details the specific technical solutions of the embodiments of the present invention.

[0043] In the RF switch circuit, the specific definition of the switching time is as follows: In the branch where conduction switching occurs, starting from the point where the control voltage is at 50%, the time required for the signal amplitude at the RF output terminal to reach 90% is the conduction switching time. In the branch where turn-off switching occurs, starting from the point where the control voltage is at 50%, the time required for the signal amplitude at the RF output terminal to reach 10% is the turn-off switching time.

[0044] As one of the important performance indicators of the RF switch, the switching time is fundamentally determined by the RC time constant representing the transient response in the switch circuit, and is positively correlated with the magnitudes of the equivalent capacitance and equivalent resistance of the switch branch. Among them, the equivalent capacitance of the switch branch mainly includes the gate-source, gate-drain parasitic capacitances and series DC-blocking capacitances in the branch, and the equivalent resistance mainly includes the gate resistance of the switch transistor and the source-drain equivalent resistance in the branch.

[0045] In the radio frequency front-end module of a mobile communication system, the main function of the radio frequency switch is to switch the transmission path of radio frequency signals. According to the different compositions of the communication system, its forms include single-pole double-throw (SPDT) or single-pole multi-throw (SP3T, SP4T, SP5T), etc. Here, an example of a radio frequency front-end module architecture in an existing Wi-Fi system will be used for illustration.

[0046] As Figure 3 shown, the radio frequency front-end module includes at least one power amplifier (PA) transmission path and one bypass transmission path, as well as at least one low-noise amplifier (LNA) reception path and one bypass reception path. Among them, the power amplifier (PA) and the low-noise amplifier (LNA) are powered by separate low-dropout linear regulators (LDOs).

[0047] In this front-end module architecture, by turning on or off the radio frequency switches S1 at the antenna end and S2 at the transmission end, the front-end system can achieve five working modes, namely RX gain (amplified reception), RX bypass (bypass reception), TX gain (amplified transmission), BT gain (Bluetooth amplified transmission), and BT bypass (Bluetooth bypass reception).

[0048] In order to improve the transmission rate of the Wi-Fi front-end system and reduce the switching time between various working modes, in addition to configuring an LDO with strong load-carrying capacity to quickly power on the power amplifier PA and the low-noise amplifier LNA, the establishment time of the radio frequency signal path highly depends on the switching time of the radio frequency switches in the signal path. Therefore, in order to overcome the problems existing in the radio frequency switch circuit in the prior art, while ensuring performance indicators such as power handling capacity and linearity and without increasing costs, the present invention provides a radio frequency switch circuit with fast switching, which can reduce the switching time of the radio frequency switch circuit and improve the transmission rate of the communication system.

[0049] As Figure 4As shown, in an embodiment of the present invention, a fast-switching radio frequency (RF) switch circuit includes a series switch branch M1 and a parallel switch branch M3 of at least one transmit path, and a series switch branch M2 and a parallel switch branch M4 of at least one receive path. Among them, after one end of the series switch branch M1 of the transmit path is connected to one end of the parallel switch branch M3, they are jointly connected to the transmit end TX. The other end of the series switch branch M1 is connected to the antenna end (ANT). The other end of the parallel switch branch M3 is connected to the ground potential end. One end of the series switch branch M2 of the receive path is connected to one end of the parallel switch branch M4, and they are jointly connected to the receive end RX. The other end of the series switch branch M2 is connected to the antenna end (ANT). The other end of the parallel switch branch M4 is connected to the ground potential end.

[0050] In an embodiment of the present invention, the series and parallel switch branches in each transmit path and receive path adopt a stacked structure of switching transistors, which are formed by sequentially connecting the source-drain electrodes of multiple switching transistors in series. Among them, the number of series switching transistors is designed and selected according to the power of the RF signal and the requirements of ESD (electrostatic protection). Figure 4 The shown switch branch takes four switching transistors connected in series as an example. In the switching transistors of the stacked structure, the body electrode of each switching transistor is connected to the ground potential end through a body bias resistor, the drain and source electrodes are respectively connected to the ground potential end through a drain bias resistor and a source bias resistor, and the gate electrodes are connected to the bias voltage Vg through a gate bias resistor.

[0051] When the RF switch is in the transmit operating mode, as Figure 4 shown, in the series switch branch M1 of the transmit path and the parallel switch branch M4 of the receive path, the gate bias voltage Vg of the switching transistors is the positive voltage VDD (usually 2.5 - 3.8V); in the parallel switch branch M3 of the transmit path and the series switch branch M2 of the receive path, the gate bias voltage Vg of the switching transistors is the ground potential (usually 0V). Therefore, the series switch branch M1 of the transmit path conducts to close the transmit path, and the parallel switch branch M3 turns off to enable the transmit path to work properly. At this time, the RF signal is transmitted from the transmit end TX to the antenna end through the transmit path; the series switch branch M2 of the receive path turns off to disconnect the receive path, and the parallel switch branch M4 conducts to ground to isolate the receive and transmit paths from each other.

[0052] When the RF switch is in the receive operating mode, as Figure 5As shown, in the series switch branch M2 of the receiving path and the parallel switch branch M3 of the transmitting path, the gate bias voltage Vg of the switching transistor is the positive voltage VDD; in the parallel switch branch M4 of the receiving path and the series switch branch M1 of the transmitting path, the gate bias voltage Vg of the switching transistor is at the ground potential. Therefore, when the series switch branch M2 of the receiving path is turned on to close the receiving path and the parallel switch branch M4 is turned off to enable the receiving path to operate normally, at this time, the RF signal is transmitted from the antenna terminal to the receiving end RX through the transmitting path; the series switch branch M1 of the transmitting path is turned off to disconnect the transmitting path, and the parallel switch branch M3 is turned on to ground to isolate the receiving and transmitting paths from each other.

[0053] Compared with the relative negative voltage type RF switch in the prior art, in the RF switch circuit provided by the present invention, during the signal path switching process, since the source-drain electrodes of the series switching transistors in the conducting branch and the non-conducting branch are both at the ground potential, therefore, the large series DC blocking capacitor in the branch is eliminated, thereby reducing the switching time of the RF switch circuit.

[0054] Meanwhile, in an embodiment of the present invention, in order to improve the linearity of the RF switch, as Figure 4 shown, at one end of the series switch branch M2 of the receiving path connected to the receiving end RX, a parallel small capacitor C2 is added between the gate and source of the switching transistor. When the RF switch is in the transmitting operating mode and the RF signal is transmitted from the transmitting end TX to the antenna terminal through the transmitting path, in the series switch branch M2 of the receiving path, due to the parasitic capacitance existing between the gate-source and gate-drain of the series switching transistor, there will be a certain amplitude of RF signal at the gate, which reduces the linearity of the switch. After adding the parallel small capacitor C2, the conductance between the gate and source of the switching transistor increases, effectively pulling down the signal amplitude at the gate, making the series switch branch M2 of the receiving path in a better off state, thereby improving the linearity of the RF switch.

[0055] Similarly, as Figure 6 shown, on the basis of the above technical solution, parallel small capacitors C1 and C2 can also be added at both ends of the series switch branch M2 of the receiving path, where the small capacitor C1 is connected in parallel between the gate and drain of the switching transistor at the antenna terminal. When the RF switch is in the transmitting operating mode and the RF signal is transmitted from the transmitting end TX to the antenna terminal, after adding the parallel small capacitors C1 and C2, the conductance between the gate-drain and gate-source of the switching transistor increases, effectively pulling down the signal amplitude at the gate, making the series switch branch M2 of the receiving path in a good off state, thereby further improving the linearity of the RF switch.

[0056] In another embodiment of the present invention, in order to improve the linearity of the RF switch, as Figure 7As shown in the figure, at one end of the parallel switch branch M3 in the transmission path connected to the ground potential terminal, a parallel small capacitor C4 is added between the gate and source of the switching transistor; alternatively, at both ends of the parallel switch branch M3 in the transmission path, parallel small capacitors C3 and C4 are respectively added. Among them, the small capacitor C3 is connected in parallel between the gate and drain of the switching transistor. When the RF switch is in the transmission operating mode and the RF signal is transmitted from the transmitter TX to the antenna terminal through the transmission path, after adding the parallel small capacitor C4, or after adding the parallel small capacitors C3 and C4, the parallel switch branch M3 of the transmission path is in a good off state, preventing the RF signal from leaking to the ground, thereby improving the linearity of the RF switch. The working principle of this embodiment is the same as that of the above embodiment, so it will not be elaborated here.

[0057] It should be noted that in other embodiments of the present invention, the above several RF switch technical solutions for improving linearity can also be combined to form new technical solutions to optimize the linearity of the RF switch.

[0058] In order to verify the improvement of the switching time performance index of the RF switch circuit provided by the embodiments of the present invention, the inventors Figure 4 the technical solution of the present invention shown in the figure and Figure 2 the prior art solution shown in the figure were respectively subjected to simulation tests on the switching time of the RF switch. The following takes the working mode of the RF front-end module switching from the transmission mode (TX mode) to the reception mode (RX mode) as an example to conduct a simulation test on the RF switch at the antenna terminal, and the test results are as follows.

[0059] As Figure 8 shown, it is the simulation test result of the relative negative voltage type RF switch circuit in the prior art. Point A in the figure is the time point when the control signal rises to 50%, and point B is the time point when the amplitude of the RF signal at the receiving end reaches 90%. It can be seen from the figure that when the signal path switches from the transmission path to the reception path, the switching time of the RF switch using the prior art solution is 496 ns.

[0060] As Figure 9 shown, it is the simulation test result of the RF switch circuit using the technical solution of the present invention. Point A in the figure is the time point when the control signal rises to 50%, and point B is the time point when the amplitude of the RF signal at the receiving end reaches 90%. It can be seen from the figure that when the signal path switches from the transmission path to the reception path, the switching time of the RF switch using the technical solution of the present invention is 266 ns. Compared with the prior art solution, the switching time of the RF switch provided by the present invention is reduced by 230 ns, effectively improving the transmission rate of the communication system.

[0061] An embodiment of the present invention further provides an integrated circuit chip. The integrated circuit chip includes the above-mentioned radio frequency switch circuit with fast switching, which is used in the radio frequency front-end module of a wireless communication system. Its function is to accurately synchronously switch the transmission path of radio frequency signals and select the corresponding radio frequency path. The specific structure of the radio frequency switch circuit based on fast switching in the integrated circuit chip will not be elaborated here.

[0062] In addition, the radio frequency switch circuit provided by the present invention can also be used in an electronic device as an important part of a communication component. The electronic device mentioned here refers to a computer device that can be used in a mobile environment and supports multiple communication systems such as GSM, EDGE, TD_SCDMA, TDD_LTE, FDD_LTE, etc., including mobile phones, laptop computers, tablet computers, in-vehicle computers, etc. In addition, the technical solution provided by the present invention is also applicable to other occasions where radio frequency switches are applied, such as communication base stations, intelligent networked vehicles, etc.

[0063] As Figure 10 shown, the electronic device includes at least a processor and a memory, and may further include a communication component, a sensor component, a power supply component, a multimedia component, and an input / output interface according to actual needs. Among them, the memory, communication component, sensor component, power supply component, multimedia component, and input / output interface are all connected to the processor. The memory can be a static random access memory (SRAM), an electrically erasable programmable read-only memory (EEPROM), an erasable programmable read-only memory (EPROM), a programmable read-only memory (PROM), a read-only memory (ROM), a magnetic memory, a flash memory, etc. The processor can be a central processing unit (CPU), a graphics processing unit (GPU), a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), a digital signal processing (DSP) chip, etc. Other communication components, sensor components, power supply components, multimedia components, etc. can all be implemented by general components and will not be specifically described here.

[0064] In summary, compared with the prior art, the fast-switching RF switch circuit, chip and electronic device provided by the present invention achieve fast switching of the working mode of the RF front-end system through the optimized design of the RF switch circuit, while ensuring performance indicators such as power handling capacity and linearity and without increasing costs, thereby improving the transmission rate of the communication system. Therefore, the fast-switching RF switch circuit provided by the present invention has beneficial effects such as ingenious and reasonable design, simple structure, low cost, small switching time, high linearity, etc. The above has described in detail the fast-switching RF switch circuit, chip and electronic device provided by the present invention. For those of ordinary skill in the art, any obvious changes made to it without departing from the essential content of the present invention will fall within the protection scope of the patent right of the present invention.

Claims

1. A fast-switching radio frequency switch circuit, characterized in that A series switching branch and a parallel switching branch including at least one transmitting path, and a series switching branch and a parallel switching branch of at least one receiving path; wherein, In the transmitting path, two ends of the series switching branch are respectively connected to a transmitting end and an antenna end, and two ends of the parallel switching branch are respectively connected to the transmitting end and a ground potential end; In the receiving path, two ends of the series switching branch are respectively connected to a receiving end and an antenna end, and two ends of the parallel switching branch are respectively connected to the receiving end and a ground potential end; The series switching branch and the parallel switching branch are formed by multiple switch transistors connected in series between the drain and the source in sequence, and no series DC blocking capacitor is included; the drain and the source of each switch transistor are respectively connected to the ground potential end through a drain bias resistor and a source bias resistor; When the transmitting path is in the working state, the series switching branch in the transmitting path is closed, and the parallel switching branch in the transmitting path is opened; when the transmitting path is in the non-working state, the series switching branch in the transmitting path is opened, and the parallel switching branch in the transmitting path is closed; when the receiving path is in the working state, the series switching branch in the receiving path is closed, and the parallel switching branch in the receiving path is opened; when the receiving path is in the non-working state, the series switching branch in the receiving path is opened, and the parallel switching branch in the receiving path is closed.

2. The fast-switching radio frequency switch circuit according to claim 1, wherein: Both the series switching branch and the parallel switching branch adopt a switch transistor stacking structure; The body terminal of each switch transistor is connected to the ground potential end through a body bias resistor, and the gate terminal is connected to a bias voltage through a gate bias resistor.

3. The fast-switching radio frequency switch circuit according to claim 1 or 2, characterized in that When the radio frequency switch is in the transmitting working mode: For the series switching branch of the transmitting path in the working state and the parallel switching branch of the receiving path, the gate bias voltage of the switch transistor is a positive voltage; For the parallel switching branch of the transmitting path in the working state and the series switching branch of the receiving path, and the series switching branch of the transmitting path not in the working state, the gate bias voltage of the switch transistor is the ground potential.

4. The fast-switching radio frequency switch circuit according to claim 1 or 2, characterized in that When the radio frequency switch is in the receiving working mode: For the series switching branch of the receiving path in the working state and the parallel switching branch of the transmitting path, the gate bias voltage of the switch transistor is a positive voltage; For the parallel switching branch of the receiving path in the working state and the series switching branch of the transmitting path, and the series switching branch of the receiving path not in the working state, the gate bias voltage of the switch transistor is the ground potential.

5. The fast-switching radio frequency switch circuit according to claim 2, wherein: At one end of the series switching branch of the receiving path connected to the receiving end, a first parallel capacitor is added, and two ends of the parallel capacitor are respectively connected to the gate and the source of the switch transistor to improve the linearity of the radio frequency switch.

6. The fast-switching radio frequency switch circuit according to claim 2, wherein: A first parallel capacitor and a second parallel capacitor are respectively added at both ends of the series switch branch of the receiving path. Among them, both ends of the first parallel capacitor are respectively connected to the gate and source of the switch transistor on the receiving end side, and both ends of the second parallel capacitor are respectively connected to the gate and drain of the switch transistor on the antenna end side, for improving the linearity of the radio frequency switch.

7. The fast-switching radio frequency switch circuit according to claim 2, wherein: A third parallel capacitor is added to one end of the parallel switch branch of the transmitting path connected to the ground potential terminal, and both ends of this parallel capacitor are respectively connected to the gate and source of the switch transistor, for improving the linearity of the radio frequency switch.

8. The fast-switching radio frequency switch circuit according to claim 2, wherein: A third parallel capacitor and a fourth parallel capacitor are respectively added at both ends of the parallel switch branch of the transmitting path. Among them, both ends of the third parallel capacitor are respectively connected to the gate and source of the switch transistor on the ground potential end side, and both ends of the fourth parallel capacitor are respectively connected to the gate and drain of the switch transistor on the transmitting end side, for improving the linearity of the radio frequency switch.

9. An integrated circuit chip, characterized in that Comprising the fast-switching radio frequency switch circuit according to any one of claims 1 to 8.

10. An electronic device, characterized in that Comprising the fast-switching radio frequency switch circuit according to any one of claims 1 to 8.

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