A power selector circuit and radio frequency switch

Abstract

The application discloses a power selector circuit and a radio frequency switch, and has simple and reasonable circuit structure, which can save system space and cost; the power selector circuit is connected with voltage sources V1 and V2; when the voltage source V1 is high, the voltage source V2 is low; when the voltage source V1 is low, the voltage source V2 is high; the power selector circuit is a symmetrical structure; the power selector circuit comprises first to fourth voltage division modules and first to fifth switch modules; one end of the first voltage division module is connected with the voltage source V2; one end of the second voltage division module is connected with the voltage source V1; two ends of the third voltage division module are connected with the voltage sources V1 and V2 respectively; the radio frequency switch comprises a shell and a radio frequency switch chip; the radio frequency switch chip comprises a power selector, a voltage converter, an oscillator and a negative voltage generating circuit, a driving stage and a radio frequency switch stage which are connected in sequence; the power selector adopts the power selector circuit.

Description

Technical Field

[0001] The present invention relates to the technical field of radio frequency switches, and in particular to a power selector circuit and a radio frequency switch. Background Art

[0002] Radio frequency switches are widely used in mobile phones, computers, and other devices to switch between receiving and transmitting radio frequency signals. Commonly used RF switches include single-pole double-throw (SPDT) and single-pole triple-throw (SPTT) switches. In the field of Wi-Fi (Wi-Fi) communications, the RF front-end Wi-Fi switch chip typically receives an operating voltage from a voltage source (VDD) and a control signal from a control voltage (VCTRL). The voltage source (VDD) typically ranges from 2.5V to 4.5V, while the high-level voltage of the control voltage (VCTRL) ranges from 1.6V to 3.6V. To meet the switching control requirements of the RF switch, two voltage conversion modules are required to convert the voltage source (VDD) and the control voltage (VCTRL), respectively.

[0003] like Figure 1 As shown, the voltage source VDD and the control voltage VCTRL are converted into corresponding internal control signals by the voltage converter module and the level converter module respectively. The voltage converter module converts the external voltage source VDD into two sets of internal bias voltages Vreg_ana and Vreg_dig. Both sets of voltages are lower than 3V to meet the safe operating requirements of the internal SOI MOS transistor (the rated operating voltage of the SOI MOS transistor is 2.5V). The high level of the external control signal VCTRL is 1.6V~3.6V, which is converted into the internal control signal BS by the level converter module, wherein the high level of the control signal BS is equal to Vreg_ana. The internal voltage Vreg_dig powers the oscillator and the negative voltage generating circuit to generate a negative voltage Vneg. The driver stage is jointly powered by the bias voltage Vreg_ana and the negative voltage Vneg. Its function is to convert the control signal BS into the actual bias voltages Vg1, Vg2, Vb1, and Vb2 of the RF switch stage to control the on or off of the RF switch stage. It can be seen that the voltage source VDD and the control voltage VCTRL in the currently commonly used RF switch chips come from two different voltage domains, that is, different voltage source modules are used to provide the voltage source VDD and the control voltage VCTRL respectively. The setting of different voltage source modules not only increases the design complexity of the entire RF front-end system, but also increases the hardware resource investment cost, and occupies more space, which cannot meet the miniaturization requirements of the RF switch. Summary of the Invention

[0004] In view of the problem in the prior art that the voltage source VDD and control voltage VCTRL in the RF switch chip come from two different voltage domains, which not only increases the design complexity of the entire RF front-end system and the hardware resource investment, but also occupies more internal space of the RF switch chip and cannot meet the miniaturization requirements of the RF switch, the present invention provides a power selector circuit and an RF switch, whose circuit structure design is simple and reasonable, can save system space and cost, and ensure the working stability and reliability of the RF switch.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A power selector circuit, wherein a power supply terminal is connected to voltage sources V1 and V2, and the power selector circuit is used to select the input voltage sources V1 and V2, characterized in that when the voltage source V1 is at a high level, the voltage source V2 is at a low level, and conversely, when the voltage source V1 is at a low level, the voltage source V2 is at a high level;

[0007] The power selector circuit has a symmetrical structure and includes first to fourth voltage divider modules and first to fifth switch modules. One end of the first voltage divider module is connected to the voltage source V2, one end of the second voltage divider module is connected to the voltage source V1, and two ends of the third voltage divider module are respectively connected to the voltage sources V1 and V2. One end of the first switch module is respectively connected to the voltage source V1 and the input end of the fourth voltage divider module. The other end of the first switch module is respectively connected to one end of the third switch module and the first output end of the fourth voltage divider module. One end of the second switch module is respectively connected to the voltage source V2 and the input end of the fifth voltage divider module. The other end of the second switch module is respectively connected to one end of the fourth switch module and the first output end of the fifth voltage divider module. The second output end of the fourth voltage divider module, the second output end of the fifth voltage divider module, the other end of the third switch module, and the other end of the fourth switch module are connected.

[0008] The first voltage divider module is used to divide the voltage of the voltage source V2, and the other end of the first voltage divider module outputs a voltage V1IP;

[0009] The second voltage divider module is used to divide the voltage of the voltage source V1, and the other end of the second voltage divider module outputs a voltage V2IP;

[0010] The third voltage dividing module is used to divide the voltages of the voltage sources V1 and V2, and the output end of the third voltage dividing module outputs a voltage VMID;

[0011] The fourth voltage dividing module and the fifth voltage dividing module are both used for internal voltage division to obtain the internal voltage VDD_INT;

[0012] The first to fifth switch modules are each composed of a plurality of MOS transistors, and the MOS transistors in the first and second switch modules are controlled by corresponding voltages V1IP, V2IP, and VMID;

[0013] The MOS transistors in the third switch module and the fourth switch module are controlled by corresponding voltages V1IP and V2IP.

[0014] It is further characterized in that

[0015] The fourth voltage divider module includes diodes D1 and D2 connected in parallel, the anode of the diode D1 is respectively connected to the anode of the diode D2, one end of the first switch module, and the voltage source V1, the cathode of the diode D1 is the first output end of the fourth voltage divider module, and is respectively connected to the other end of the first switch module and one end of the third switch module, and the cathode of the diode D2 is the second output end of the fourth voltage divider module;

[0016] The fifth voltage divider module includes diodes D3 and D4 connected in parallel, the anode of the diode D3 is respectively connected to the anode of the diode D4, one end of the second switch module, and the voltage source V2, the cathode of the diode D3 is the first output end of the fifth voltage divider membrane, and is respectively connected to the other end of the second switch module and one end of the fourth switch module, and the cathode of the diode D4 is the second output end of the fifth voltage divider module;

[0017] The first switch module includes a MOS transistor M1 and a MOS transistor M2 connected in parallel, and a MOS transistor M3 connected in series with the MOS transistor M2. The source of the MOS transistor M1 is respectively connected to the source of the MOS transistor M2, the voltage source V1, the anode of the diode D1, and the anode of the diode D2. The drain of the MOS transistor M1 is respectively connected to the cathode of the diode D2, the source of the MOS transistor M3, and the sources of the MOS transistors M7 and M8 in the third switch module. The drain of the MOS transistor M2 is connected to the drain of the MOS transistor M3.

[0018] The second switch module includes a MOS transistor M4, a MOS transistor M5, and a MOS transistor M6. The source of the MOS transistor M4 is respectively connected to the source of the MOS transistor M5, the anode of the diode D3, and the anode of the diode D4. The drain of the MOS transistor M4 is respectively connected to the source of the MOS transistor M6 and the sources of the MOS transistors M10 and M11 in the fourth switch module. The drain of the MOS transistor M5 is connected to the drain of the MOS transistor M6.

[0019] The third switch module includes the MOS transistor M7, the MOS transistor M8, and the MOS transistor M9. The drain of the MOS transistor M7 is respectively connected to the source of the MOS transistor M9, the drain of the MOS transistor M10 and the drain of the MOS transistor M12 in the fourth switch module, the cathode of the diode D2, and the cathode of the diode D4. The drain of the MOS transistor M8 is connected to the drain of the MOS transistor M9.

[0020] The fourth switch module includes the MOS transistor M10, the MOS transistor M11, and the MOS transistor M12, and the drain of the MOS transistor M11 is connected to the drain of the MOS transistor M12;

[0021] The first voltage divider module includes a resistor R1, one end of which is connected to the voltage source V2, and the other end of which is respectively connected to the gate of the MOS transistor M2 in the first switch module, the gate of the MOS transistor M6 in the second switch module, the gates of the MOS transistors M7 and M8 in the third switch module, and the gate of the MOS transistor M12 in the fourth switch module;

[0022] The second voltage divider module includes a resistor R2, one end of which is connected to the voltage source V1, and the other end of which is respectively connected to the gate of the MOS transistor M3 in the first switch module, the gate of the MOS transistor M5 in the second switch module, the gate of the MOS transistor M9 in the third switch module, and the gates of the MOS transistors M10 and M11 in the fourth switch module;

[0023] The third voltage divider module includes resistors R3 and R4 connected in series, one end of the resistor R3 is connected to the voltage source V1, one end of the resistor R4 is connected to the voltage source V2, and the other end of the resistor R3 is respectively connected to the other end of the resistor R4, the gate of the MOS transistor M1 in the first switch module, and the gate of the MOS transistor M4 in the second switch module;

[0024] The diodes D1 to D4 are of model TN330 or TN3318;

[0025] The MOS tubes M1 to M12 are all PMOS tubes;

[0026] The output voltage VMID of the output terminal of the third voltage divider module is calculated as follows: VMID=1 / 2*(V1+V2);

[0027] The high level of the voltage sources V1 and V2 is 1.6V to 3.6V, and the low level is 0V.

[0028] A radio frequency switch comprises a housing and a radio frequency switch chip encapsulated in the housing, characterized in that the radio frequency switch chip comprises a power selector, a voltage converter, an oscillator and a negative voltage generating circuit, a driver stage, and a radio frequency switch stage connected in sequence, the power selector adopting the above-mentioned power selector circuit, the input end of the power selector inputting voltage sources V1 and V2 for selecting the voltage sources V1 and V2, the voltage converter being used to convert the voltage VDD_INT output by the power selector into bias voltages Vreg_ana and Vreg_dig, the bias voltage Vreg_dig being used to power the oscillator and the negative voltage generating circuit, the oscillator and the negative voltage generating circuit being used to generate a negative voltage Vneg, the bias voltage Vreg_ana and the negative voltage Vneg being used to power the driver stage, the input end of the driver stage also inputting a control signal BS, the output end of the driver stage outputting control voltage signals Vg1, Vg2, Vb1, and Vb2, the control voltage signals Vg1, Vg2, Vb1, and Vb2 being used to control switches in the radio frequency switch stage.

[0029] The above-mentioned structure of the present invention can achieve the following beneficial effects: the power selector circuit structure of the present application is symmetrical. When the voltage source V1 is at a high level, the voltage source V2 is at a low level. Conversely, when the voltage source V1 is at a low level, the voltage source V2 is at a high level. In addition, the first switch module and the third switch module in the power selector are symmetrically arranged with the second switch module and the fourth switch module, respectively. Therefore, the high and low levels of the external input voltage sources V1 and V2 can be switched by the MOS tubes in the first to fourth switch modules in the power selector to achieve the selection of the voltage sources V1 and V2, thereby providing a continuous control signal for the subsequent circuit. A set of voltage conversion modules corresponding to the output end can meet the power supply and control requirements of the subsequent circuit. The circuit structure is simple, which is conducive to saving system space and cost.

[0030] In addition, the voltage sources V1 and V2 of the present application are arranged at the front end of the entire RF switch system, that is, the currently commonly used voltage source VDD and control voltage VCTRL are replaced by voltage source V1 or V2. Here, the voltage source V1 / V2 serves as a power supply to provide power supply voltage for the RF switch chip, and also provides a control signal to control the corresponding RF switch to be turned on or off. The high levels of the voltage sources V1 and V2 are in the same voltage domain in the entire RF front-end system. Therefore, when designing the RF front-end system, only one voltage domain needs to be designed, which makes the design simpler and reduces hardware resource investment and cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a circuit structure diagram of an existing RF switch chip;

[0032] Figure 2is a circuit schematic diagram of the power selector circuit of the present invention;

[0033] Figure 3 This is a circuit structure block diagram of the radio frequency switch chip of the present invention. DETAILED DESCRIPTION

[0034] Different embodiments or examples are provided below to implement different structures of the present invention. In order to simplify the disclosure of the present invention, the components and settings of specific examples are described below. Of course, they are merely examples and are not intended to limit the present invention. In addition, the present invention may repeat reference numerals and / or reference letters in different examples. This repetition is for the purpose of simplicity and clarity and does not in itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present invention provides examples of various specific processes and materials, but those of ordinary skill in the art will appreciate the application of other processes and / or the use of other materials.

[0035] Figure 1 A currently common RF switch chip circuit structure is provided, which includes a voltage converter 1, a level converter 2, an oscillator and a negative voltage generating circuit 3, a driver stage 4, and an RF switch stage 5. The voltage converter module 1 converts the external power supply voltage VDD into two internal voltages Vreg_ana and Vreg_dig. Both voltages are lower than 3V, meeting the safety working requirements of subsequent internal SOI nominal 2.5V devices. The high level of the external control signal VCTRL is 1.6V to 3.6V, which needs to be converted by the level converter 2 into an internal control signal BS, where the high level of BS is equal to Vreg_ana. The internal voltage Vreg_dig powers the oscillator and the negative voltage generating circuit 3, so that it generates Negative voltage circuit Vneg; the driving stage is jointly powered by Vreg_ana and the negative voltage Vneg, and its function is to convert the control signal BS into the actual bias voltages Vg1, Vg2, Vb1, and Vb2 of the RF switch stage 5 to control the opening or closing of the RF switch stage. It can be seen that the voltage source VDD and the control voltage VCTRL in the currently commonly used RF switch chips come from two different voltage domains, that is, the voltage source VDD and the control voltage VCTRL are respectively provided by different voltage source modules. The setting of different voltage source modules not only increases the design complexity of the entire RF front-end system, but also increases the hardware resource investment cost, and occupies more space, which cannot meet the miniaturization requirements of the RF switch.

[0036] In order to solve the problem that the voltage source VDD and control voltage VCTRL in the RF switch chip in the prior art come from two different voltage domains, which not only increases the design complexity of the entire RF front-end system and the hardware resource investment, but also occupies a large amount of internal space of the RF switch chip, and cannot meet the miniaturization requirements of the RF switch, in a specific embodiment of the present invention, a power selector circuit and an RF switch are provided, and the switch in the RF switch stage 5 is a single-pole double-throw switch. Figure 2 The power supply end of the power selector circuit is connected to the voltage sources V1 and V2. The power selector circuit 6 is used to select the input voltage sources V1 and V2. When the voltage source V1 is at a high level, the voltage source V2 is at a low level. Conversely, when the voltage source V1 is at a low level, the voltage source V2 is at a high level. In this embodiment, the high levels of the voltage sources V1 and V2 are both 1.6V to 3.6V, and the low levels are both 0V.

[0037] The power selector circuit 6 has a symmetrical structure and includes a first voltage divider module 61 to a fifth voltage divider module 65 and a first switch module 66 to a fifth switch module 70. One end of the first voltage divider module 61 is connected to the voltage source V2, one end of the second voltage divider module 62 is connected to the voltage source V1, and two ends of the third voltage divider module 63 are connected to the voltage sources V1 and V2, respectively. One end of the first switch module 66 is connected to the voltage source V1 and the input end of the fourth voltage divider module 64, respectively. The other end of the first switch module 66 is connected to one end of the third switch module 68 and the first output end of the fourth voltage divider module 64, respectively. One end of the second switch module 67 is connected to the voltage source V2 and the input end of the fifth voltage divider module 65, respectively. The other end of the second switch module 67 is connected to one end of the fourth switch module 69 and the first output end of the fifth voltage divider module 65, respectively. The second output end of the fourth voltage divider module 64, the second output end of the fifth voltage divider module 65, the other end of the third switch module 68, and the other end of the fourth switch module 69 are connected.

[0038] The first voltage divider module 61 is used to divide the voltage of the voltage source V2, and the other end of the first voltage divider module 61 outputs the voltage V1IP; the second voltage divider module 62 is used to divide the voltage of the voltage source V1, and the other end of the second voltage divider module 62 outputs the voltage V2IP; the third voltage divider module 63 is used to divide the voltages of the voltage sources V1 and V2, and the output end of the third voltage divider module 63 outputs the voltage VMID; the fourth voltage divider module 64 and the fifth voltage divider module 65 are both used for internal voltage division to obtain the internal voltage VDD_INT; the first switch module 66 to the fifth switch module 70 are each composed of a plurality of MOS transistors, and the MOS transistors in the first switch module 66 and the second switch module 67 are controlled by the corresponding voltages V1IP, V2IP, and VMID; the MOS transistors in the third switch module 68 and the fourth switch module 69 are controlled by the corresponding voltages V1IP and V2IP.

[0039] The specific circuit structure of the power selector circuit is as follows: the fourth voltage divider module 64 includes diodes D1 and D2 connected in parallel, the anode of diode D1 is respectively connected to the anode of diode D2, one end of the first switch module 66, and the voltage source V1, the cathode of diode D1 is the first output end of the fourth voltage divider module 64, and is respectively connected to the other end of the first switch module 66 and one end of the third switch module 68, and the cathode of diode D2 is the second output end of the fourth voltage divider module 69.

[0040] The fifth voltage divider module 70 includes diodes D3 and D4 connected in parallel, the anode of diode D3 is respectively connected to the anode of diode D4, one end of the second switch module 67, and the voltage source V2, the cathode of diode D3 is the first output end of the fifth voltage divider membrane 65, and is respectively connected to the other end of the second switch module 67 and one end of the fourth switch module 68, and the cathode of diode D4 is the second output end of the fifth voltage divider module 70.

[0041] The first switch module 66 includes a MOS transistor M1 and a MOS transistor M2 connected in parallel, and a MOS transistor M3 connected in series with the MOS transistor M2. The source of the MOS transistor M1 is respectively connected to the source of the MOS transistor M2, the voltage source V1, the anode of the diode D1, and the anode of the diode D2. The drain of the MOS transistor M1 is respectively connected to the cathode of the diode D2, the source of the MOS transistor M3, and the sources of the MOS transistors M7 and M8 in the third switch module. The drain of the MOS transistor M2 is connected to the drain of the MOS transistor M3.

[0042] The second switch module 67 includes MOS transistors M4, M5, and M6. The source of MOS transistor M4 is respectively connected to the source of MOS transistor M5, the anode of diode D3, and the anode of diode D4. The drain of MOS transistor M4 is respectively connected to the source of MOS transistor M6 and the sources of MOS transistors M10 and M11 in the fourth switch module. The drain of MOS transistor M5 is connected to the drain of MOS transistor M6.

[0043] The third switch module 68 includes MOS transistors M7, M8, and M9. The drain of MOS transistor M7 is connected to the source of MOS transistor M9, the drain of MOS transistor M10 and M12 in the fourth switch module, the cathode of diode D2, and the cathode of diode D4. The drain of MOS transistor M8 is connected to the drain of MOS transistor M9.

[0044] The fourth switch module 69 includes a MOS transistor M10 , a MOS transistor M11 , and a MOS transistor M12 . The drain of the MOS transistor M11 is connected to the drain of the MOS transistor M12 .

[0045] The first voltage dividing module 61 comprises a resistor R1, one end of the resistor R1 is connected to the voltage source V2, and the other end is connected to the gate of the MOS transistor M2 in the first switch module, the gate of the MOS transistor M6 in the second switch module, the gates of the MOS transistors M7 and M8 in the third switch module, and the gate of the MOS transistor M12 in the fourth switch module.

[0046] The second voltage dividing module 62 comprises a resistor R2, one end of the resistor R2 is connected to the voltage source V1, and the other end is connected to the gate of the MOS transistor M3 in the first switch module, the gate of the MOS transistor M5 in the second switch module, the gate of the MOS transistor M9 in the third switch module, and the gates of the MOS transistors M10 and M11 in the fourth switch module.

[0047] The third voltage dividing module 63 comprises resistors R3 and R4 connected in series, one end of the resistor R3 is connected to the voltage source V1, one end of the resistor R4 is connected to the voltage source V2, and the other end of the resistor R3 is connected to the other end of the resistor R4, the gate of the MOS transistor M1 in the first switch module, and the gate of the MOS transistor M4 in the second switch module. In this embodiment, the MOS transistors M1 to M12 are PMOS transistors.

[0048] Taking the voltage source V1 as 3.6V and the voltage source V2 as 0V as an example, the voltage source V1 is the power supply, the voltage V2IP is obtained by dividing the voltage source V1 through the resistor R2 in the second voltage dividing module, the voltage V2IP is used as the gate drive voltage of the MOS transistors M3, M5, M9, M10, and M11 in the first switch module to the fourth switch module, the voltage V1IP is obtained by dividing the voltage source V2 through the resistor R1 in the first voltage dividing module, the voltage V1IP is used as the gate drive voltage of the MOS transistors M2, M6, M7, M8, and M12 in the first switch module to the fourth switch module, the resistors R3 and R4 in the third voltage dividing module are used to divide the voltages V1 and V2 respectively, and the voltage VMID is obtained, the calculation method of the voltage VMID is: VMID = 1 / 2*(V1+V2), the voltage VMID is used to provide the gate drive voltage for the corresponding MOS transistors M1 and M4 in the first switch module and the second switch module, and the diodes D1, D2, D3, and D4 in the fourth voltage dividing module and the fifth voltage dividing module are used to divide the internal voltage to obtain the internal voltage source VDD_INT, VDD_INT is equal to V1. When the MOS transistor M10 is closed and the MOS transistor M4 is closed, the diodes D1, D2, D3, and D4 ensure that the working voltage of the MOS transistor M10 and the MOS transistor M4 when closed is lower than the rated working voltage, thereby preventing the MOS transistors M10 and M4 from being damaged.

[0049] The working principle of the power selector circuit is as follows: in the first to fourth switch modules, MOS tubes M1, M4, M7, and M10 are four PMOS switch tubes of the main path, and the remaining eight MOS tubes are mainly used for substrate selection.

[0050] The power selector circuit structure is symmetrical. When the voltage source V1 is at a high level, the voltage source V2 is at a low level. Conversely, when the voltage source V1 is at a low level, the voltage source V2 is at a high level. In addition, the first and third switch modules in the power selector are symmetrically arranged with the second and fourth switch modules, respectively. Therefore, the MOS transistors in the first to fourth switch modules in the power selector can switch the high and low levels of the external input voltage sources V1 and V2 to achieve selection of the voltage sources V1 and V2, thereby providing continuous control signals for subsequent circuits.

[0051] Operating Principle: When voltage source V1 is high (3.3V) and voltage source V2 is low (0V), voltage source V1IP is 0V and voltage source V2IP is 3.3V. At this point, MOS transistors M1 and M7 are turned on, MOS transistors M4 and M10 are turned off, and voltage source VDD_INT is connected to voltage source V1 at 3.3V. Simultaneously, MOS transistors M2, M8, M12, or M6 in the substrate select device are turned on, while MOS transistors M3, M9, M11, or M5 are turned off, ensuring normal circuit operation and preventing leakage through the substrate. When voltage source V1 is low and voltage source V2 is high, the operation is similar to the above and will not be further described. When both voltage sources V1 and V2 are high, all PMOS transistors are turned off, and voltage sources V1 and V2 are connected to voltage source VDD_INT via diodes D2 and D4, respectively. Diodes D1 and D3 provide auxiliary functions, ensuring that all components operate within a safe voltage range.

[0052] The present application ensures that the voltage source V1 or the voltage source V2 (V1 / V2) can be switched stably and normally through a power selector, so as to provide a stable working power supply and control voltage for the subsequent circuit. The power selector is provided with a first voltage divider module to a fifth voltage divider module. The first voltage divider module to the third voltage divider module are used to divide the voltage sources V1 and V2, and the fourth voltage divider module and the fifth voltage divider module are used to divide the internal voltage, thereby preventing the voltage values ​​of the voltage sources V1 and V2 from being large and exceeding the rated working voltage of the MOS tube, thereby preventing the MOS tube from being damaged, thereby ensuring the working stability and reliability of the RF switch.

[0053] See Figure 3The above-mentioned power selector is applied to a radio frequency switch. The radio frequency switch includes a shell and a radio frequency switch chip encapsulated in the shell. The radio frequency switch chip includes a power selector, a voltage converter, an oscillator and a negative voltage generating circuit, a driver stage, and a radio frequency switch stage connected in sequence. The power selector adopts the above-mentioned power selector circuit. The input end of the power selector inputs voltage sources V1 and V2 for selecting voltage sources V1 and V2. The voltage converter is used to convert the voltage VDD_INT output by the power selector into bias voltages Vreg_ana and Vreg_dig. The bias voltage Vreg_dig is used to power the oscillator and the negative voltage generating circuit. The oscillator and the negative voltage generating circuit are used to generate a negative voltage Vneg. The bias voltage Vreg_ana and the negative voltage Vneg are used to power the driver stage. The input end of the driver stage also inputs a control signal BS. The output end of the driver stage outputs control voltage signals Vg1, Vg2, Vb1, and Vb2. The control voltage signals Vg1, Vg2, Vb1, and Vb2 are used to control the switch in the radio frequency switch stage.

[0054] For RF switch chips, a stable and equivalent power supply is required to ensure their normal operation. Therefore, this application sets voltage sources V1 and V2 and a power selector at the front end of the entire RF switch system, that is, the currently commonly used voltage source VDD and control voltage VCTRL are replaced with voltage sources V1 or V2, and the complementary high and low level inputs of the voltage source V1 / V2 are converted into a stable internal voltage VDD_INT through the power selector. The internal voltage VDD_INT provides power for the subsequent circuit, and the subsequent circuit reuses the existing circuit architecture and modules. In this way, the circuit structure of the entire RF switch chip is simple, and the reuse of existing circuits reduces design risks. At the same time, the power selector circuit module itself has a simple structure, which is conducive to saving chip area and cost. In addition, the power selector is provided with a first voltage divider module to a fifth voltage divider module. The first voltage divider module to the third voltage divider module are used to divide the voltage sources V1 and V2, and the fourth voltage divider module and the fifth voltage divider module are used to divide the internal voltage, thereby preventing the voltage values ​​of the voltage sources V1 and V2 from being large and exceeding the rated operating voltage of the MOS tube, thereby preventing the MOS tube from being damaged, thereby ensuring the working stability and reliability of the RF front-end switch.

[0055] The above are only preferred embodiments of the present application, and the present invention is not limited to the above embodiments. It is understood that other improvements and variations directly derived or imagined by those skilled in the art without departing from the spirit and concept of the present invention should be considered to be included in the scope of protection of the present invention.

Claims

1. A power selector circuit, wherein a power supply terminal is connected to voltage sources V1 and V2, and the power selector circuit is used to select the input voltage sources V1 and V2, characterized in that: When the voltage source V1 is at a high level, the voltage source V2 is at a low level; conversely, when the voltage source V1 is at a low level, the voltage source V2 is at a high level; The power selector circuit has a symmetrical structure and includes a first voltage divider module to a fifth voltage divider module and a first switch module to a fourth switch module; The first voltage dividing module is used to divide the voltage source V2 to output a voltage V1IP; The second voltage dividing module is used to divide the voltage source V1 to output a voltage V2IP; The third voltage dividing module is used to receive the voltage sources V1 and V2 and perform voltage division to output a voltage VMID; The fourth voltage divider module includes diodes D1, D2, the fifth voltage divider module includes diodes D3, D4, the fourth voltage divider module, the fifth voltage divider module are used for internal voltage division, to obtain the internal voltage VDD_INT; The first switch module includes a PMOS transistor M1, a PMOS transistor M2, and a PMOS transistor M3. The source of M1 is respectively connected to the source of M2, a voltage source V1, an anode of a diode D1, and an anode of a diode D2. The drain of M1 is respectively connected to the cathode of the diode D1, the source of M3, and the sources of PMOS transistors M7 and M8 in the third switch module. The drain of M2 is connected to the drain of M3. The gate of M1 is used to connect to the voltage VMID, the gate of M2 is used to input the voltage V1IP, and the gate of M3 is used to input the voltage V2IP. The second switch module includes a PMOS transistor M4, a PMOS transistor M5, and a PMOS transistor M6. The source of M4 is respectively connected to the source of M5, the voltage source V2, the anode of diode D3, and the anode of diode D4. The drain of M4 is respectively connected to the source of MOS transistor M6, the cathode of D3, and the sources of PMOS transistors M10 and M11 in the fourth switch module. The drain of M5 is connected to the drain of M6. The gate of M4 is used to input voltage VMID, the gate of M5 is used to input voltage V2IP, and the gate of M6 is used to input voltage V1IP. The third switch module includes the PMOS transistor M7, the PMOS transistor M8, and the PMOS transistor M9. The drain of the M7 is respectively connected to the source of the M9, the drain of the M10 in the fourth switch module, the drain of the PMOS transistor M12, the cathode of the diode D2, the cathode of the diode D4, and the voltage VDD_INT. The drain of the M8 is connected to the drain of the M9; the gate of the M7 is used to input the voltage V1IP, the gate of the M8 is used to input the voltage V1IP, and the gate of the M9 is used to input the voltage V2IP; The fourth switch module includes the PMOS transistor M10, the PMOS transistor M11, and the PMOS transistor M12. The drain of the M11 is connected to the drain of the M12. The gate of the M10 is used for the voltage V2IP, the gate of the M11 is used for the input voltage V2IP, and the gate of the M12 is used for the input voltage V1IP.

2. The power selector circuit according to claim 1, wherein: The first voltage divider module includes a resistor R1, one end of which is connected to the voltage source V2, and the other end is respectively connected to the gate of M2 in the first switch module, the gate of M6 in the second switch module, the gates of M7 and M8 in the third switch module, and the gate of M12 in the fourth switch module; the second voltage divider module includes a resistor R2, one end of which is connected to the voltage source V1, and the other end is respectively connected to the gate of M3 in the first switch module, the gate of M5 in the second switch module, the gate of M9 in the third switch module, and the gates of M10 and M11 in the fourth switch module; the third voltage divider module includes resistors R3 and R4 connected in series, one end of the resistor R3 is connected to the voltage source V1, one end of the resistor R4 is connected to the voltage source V2, and the other end of the resistor R3 is respectively connected to the other end of the resistor R4, the gate of M1 in the first switch module, and the gate of M4 in the second switch module.

3. The power selector circuit according to claim 2, wherein: The high level of the voltage sources V1 and V2 is 1.6V to 3.6V, and the low level is 0V.

4. A radio frequency switch comprising a housing and a radio frequency switch chip encapsulated in the housing, characterized in that: The RF switch chip includes a power selector, a voltage converter, an oscillator and a negative voltage generating circuit, a driver stage, and a RF switch stage connected in sequence. The power selector adopts the power selector circuit according to any one of claims 1 to 3. The input end of the power selector inputs voltage sources V1 and V2 for selecting the voltage sources V1 and V2. The voltage converter is used to convert the voltage VDD_INT output by the power selector into bias voltages Vreg_ana and Vreg_dig. The bias voltage Vreg_dig is used to power the oscillator and the negative voltage generating circuit. The oscillator and the negative voltage generating circuit are used to generate a negative voltage Vneg. The bias voltage Vreg_ana and the negative voltage Vneg are used to power the driver stage. The input end of the driver stage also inputs a control signal BS. The output end of the driver stage outputs control voltage signals Vg1, Vg2, Vb1, and Vb2. The control voltage signals Vg1, Vg2, Vb1, and Vb2 are used to control the switches in the RF switch stage.

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