Electrostatic impedance protection circuit and electronic device

Abstract

The invention relates to the technical field of electronic circuits, in particular to an electrostatic impedance protection circuit and an electronic device.The electrostatic impedance protection circuit at least comprises multiple stages of impedance protection circuits, and at least one detection control circuit is arranged between every two adjacent stages of impedance protection circuits; the input end of the first-stage impedance protection circuit in the multi-stage impedance protection circuit is electrically connected with a static power supply, and the last-stage impedance protection circuit in the multi-stage impedance protection circuit is electrically connected with the static power supply and a circuit to be protected respectively; the detection control circuit is used for detecting the output voltage of the pre-stage impedance protection circuit, and the post-stage impedance protection circuit is started when the output voltage is greater than a preset voltage and discharges the static voltage of the static power supply. The invention provides an electrostatic impedance protection circuit which is simple in structure, lower in cost and capable of realizing lower ESD (Electro-Static Discharge) voltage.

Description

Technical Field

[0001] The present application relates to the technical field of electronic circuits, and in particular, to an electrostatic impedance protection circuit and an electronic device. Background Art

[0002] The ESD (Electro-Static discharge) circuit is a necessary circuit in the chip IO (Input / Output). It is usually set near each pin inside the chip to absorb the static interference introduced into the chip from the external environment through the pins, and can protect the chip from a certain ESD voltage without damage. In RF and analog circuits, the ESD circuit is required to have small parasitic parameters and be able to quickly discharge charge to ensure that the protected circuit will not be damaged due to excessive voltage difference.

[0003] Traditional ESD circuits generally include two levels of protection circuits and current limiting devices. During ESD discharge, the voltage of the first-level ESD protection circuit is higher, and after passing through the current limiting device, the voltage of the second-level ESD protection circuit is lower. The current is discharged by the first-level ESD circuit, and the current limiting device and the second-level ESD circuit further reduce the ESD voltage of the protected circuit. If a lower ESD voltage is required, more protection circuits and current limiting devices with better current limiting effects need to be connected in series, which greatly increases the cost.

[0004] Therefore, there is an urgent need for an ESD circuit that can simultaneously meet the goals of low cost and fast current discharge. Summary of the invention

[0005] In order to solve the above technical problems, an electrostatic impedance protection circuit and an electronic device are provided in an embodiment of the present application.

[0006] In a first aspect of an embodiment of the present application, there is provided an electrostatic impedance protection circuit, comprising at least: a multi-stage impedance protection circuit, wherein at least one detection control circuit is provided between two adjacent stages of the impedance protection circuits, wherein an input end of the first stage impedance protection circuit in the multi-stage impedance protection circuit is electrically connected to an electrostatic power source, and a last stage impedance protection circuit in the multi-stage impedance protection circuit is electrically connected to the electrostatic power source and a circuit to be protected, respectively;

[0007] The detection control circuit is used to detect the output voltage of the front-stage impedance protection circuit, and the rear-stage impedance protection circuit is started when the output voltage is greater than a preset voltage, and discharges the electrostatic voltage of the electrostatic power source; wherein, the front-stage impedance protection circuit refers to an impedance protection circuit electrically connected to the detection control circuit and located at the front stage of the detection control circuit, and the rear-stage impedance protection circuit refers to an impedance protection circuit electrically connected to the detection control circuit and located at the rear stage of the detection control circuit.

[0008] In an optional embodiment of the present application, the front-stage impedance protection circuit includes: a plurality of diode devices connected in series.

[0009] In an optional embodiment of the present application, the front-stage impedance protection circuit includes:

[0010] A first diode module and a second diode module are connected in parallel, wherein the input ends of the first diode module and the second diode module are respectively electrically connected to the static power source, and the output ends of the first diode module and the second diode module are respectively grounded; wherein the first diode module and the second diode module respectively include at least two diode devices connected in series, and the connection direction of the diode device in the first diode module is opposite to that of the diode device in the second diode module.

[0011] In an optional embodiment of the present application, the subsequent impedance protection circuit at least includes:

[0012] A transistor device, wherein the control end of the transistor device is electrically connected to the detection control circuit, the first connection end of the transistor device is electrically connected to the connection point of the front-stage impedance protection circuit and the electrostatic power source, the second connection end of the transistor device is grounded, and the transistor device is started when the operating voltage of the front-stage impedance protection circuit is greater than a preset voltage, and discharges the electrostatic voltage of the electrostatic power source.

[0013] In an optional embodiment of the present application, the transistor device is an N-type transistor.

[0014] In an optional embodiment of the present application, the detection control circuit at least includes:

[0015] A first resistor device, wherein a first end of the first resistor device is electrically connected to the previous impedance protection circuit;

[0016] A second resistor device, wherein a first end of the second resistor device is electrically connected to a second end of the first resistor device and a control end of the subsequent impedance protection circuit respectively, and a second end of the second resistor device is grounded.

[0017] In an optional embodiment of the present application, the electrostatic impedance protection circuit further includes:

[0018] A current limiting device, wherein the input end of the current limiting device is electrically connected to the connection point between the front-stage impedance protection circuit and the static power source, and the output end of the current limiting device is electrically connected to the first connection end of the rear-stage impedance protection circuit.

[0019] In an optional embodiment of the present application, the current limiting device includes a plurality of capacitor devices connected in series.

[0020] In an optional embodiment of the present application, the multi-stage impedance protection circuit is a two-stage impedance protection circuit.

[0021] A second aspect of the embodiments of the present application provides an electronic device, including:

[0022] A working circuit, wherein the working circuit generates static electricity when working;

[0023] The electrostatic impedance protection circuit as described in any of the above items, wherein the input end of the electrostatic impedance protection circuit is electrically connected to the working circuit, and the electrostatic impedance protection circuit is activated when the electrostatic voltage generated by the working circuit is greater than a preset voltage, and discharges the electrostatic voltage.

[0024] The electrostatic impedance protection circuit provided in the embodiment of the present application includes a multi-stage impedance protection circuit, and at least one detection control circuit is provided between two adjacent stages of impedance protection circuits, and the adjacent subsequent stage impedance protection circuit can be controlled by the previous stage impedance protection circuit. In other words, the previous stage impedance protection circuit performs a voltage reduction or a discharge on the electrostatic voltage generated by the electrostatic power source. If the electrostatic voltage after voltage reduction or discharge is less than or equal to the preset voltage, it means that the current limiting protection function of the previous stage impedance protection circuit has eliminated the static electricity to a safe range, and will not affect or interfere with the circuit to be protected. Therefore, the subsequent stage impedance protection circuit is in a closed state (non-working state), thereby reducing the overall energy consumption under the protection function;

[0025] Secondly, if the electrostatic voltage after voltage reduction or discharge is greater than the preset voltage, it means that the current limiting protection function of the previous-stage impedance protection circuit is not sufficient to eliminate the static electricity to a safe range, and the static electricity voltage will still affect or interfere with the circuit to be protected. Therefore, the output voltage of the previous-stage impedance protection circuit is used as the control voltage of the subsequent-stage impedance protection circuit to control the startup of the subsequent-stage impedance protection circuit. Since the subsequent-stage impedance protection circuit, or the last-stage impedance protection circuit is directly connected to the electrostatic power source, the subsequent-stage impedance protection circuit can directly discharge the electrostatic voltage of the electrostatic power source quickly without going through the previous-stage impedance protection circuit, skipping the previous-stage impedance protection circuit. The delay of the anti-protection circuit is increased, and the voltage reduction time efficiency is higher; at the same time, the setting of the rear-stage impedance protection circuit can effectively prevent the failure of the overall protection caused by the failure of the front-stage impedance protection circuit. Even if the rear-stage impedance protection circuit fails completely, the front-stage impedance protection circuit can reduce the electrostatic voltage of the static power source to a lower range, thereby minimizing the interference and influence on the circuit to be protected; in addition, the embodiment of the present application is provided with a multi-stage impedance protection circuit, which can minimize the influence of the static power source on the circuit to be protected, and effectively prevent any one or several impedance protection circuits from failing without affecting the overall impedance protection effect;

[0026] In a third aspect, the embodiment of the present application includes a front-stage impedance protection circuit and a rear-stage impedance protection circuit, and uses the output voltage of the front-stage impedance protection circuit as the control voltage of the rear-stage impedance protection circuit to control the startup of the rear-stage impedance protection circuit, and directly discharges the electrostatic voltage of the electrostatic power source quickly, so that a lower output ESD voltage can be achieved under the same ESD device size; correspondingly, when achieving the same ESD voltage, a smaller-sized ESD device can be selected, which greatly reduces the parasitic parameters of the ESD;

[0027] Fourthly, the embodiments of the present application include a front-stage impedance protection circuit and a post-stage impedance protection circuit. The output voltage of the front-stage impedance protection circuit is used as the control voltage of the post-stage impedance protection circuit to control the startup of the post-stage impedance protection circuit, and the electrostatic voltage of the electrostatic power source is directly and quickly discharged. The same or even better discharge effect can be achieved without the current limiting device in the traditional solution, which greatly simplifies the circuit structure and reduces the circuit cost.

[0028] In summary, the embodiments of the present application provide an electrostatic impedance protection circuit with a simple structure, lower cost, and the ability to achieve lower ESD voltage. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0030] Figure 1 A schematic diagram of the structure of an electrostatic impedance protection circuit provided in an embodiment of the present application;

[0031] Figure 2 A schematic diagram of the structure of an electrostatic impedance protection circuit provided in an embodiment of the present application;

[0032] Figure 3 A comparison diagram of voltage simulation results of a conventional ESD circuit and an electrostatic impedance protection circuit 10 provided in an embodiment of the present application;

[0033] Figure 4 A comparison diagram of simulation results of the ESD voltage Vesd (i.e., the overall output voltage of the electrostatic impedance protection circuit 10 provided in the present application) of a traditional ESD circuit and the electrostatic impedance protection circuit 10 provided in the embodiment of the present application;

[0034] Figure 5 A schematic diagram of the structure of an electrostatic impedance protection circuit provided by an embodiment of the present application;

[0035] Figure 6 A schematic diagram of the structure of an electrostatic impedance protection circuit provided by an embodiment of the present application.

[0036] 10. Electrostatic impedance protection circuit; 100. Front-stage impedance protection circuit; 110. First diode module; 120. Second diode module; 200. Detection control circuit; 300. Post-stage impedance protection circuit; 400. Current limiting device; 20. Electrostatic power source; 30. Circuit to be protected. DETAILED DESCRIPTION

[0037] In the process of realizing the present application, the applicant discovered that there is an urgent need for an ESD circuit that can simultaneously meet the goals of low cost and fast current discharge.

[0038] In view of the above problems, an electrostatic impedance protection circuit and an electronic device are provided in the embodiments of the present application. In order to make the purpose, technical solution and advantages of the present application more clear, the following embodiments and the accompanying drawings are used to further describe an electrostatic impedance protection circuit and an electronic device of the present application. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0039] The serial numbers assigned to the components herein, such as "first", "second", etc., are only used to distinguish the objects described and do not have any order or technical meaning. The "connection" and "coupling" mentioned in this application, unless otherwise specified, include direct and indirect connections (couplings). In the description of this application, it should be understood that the orientation or position relationship indicated by the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc. are based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to this application.

[0040] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0041] The electrostatic impedance protection circuit provided in the embodiment of the present application is applied to a circuit or electronic device containing an electrostatic source, and the electrostatic source can be any circuit, electronic device or external environment, and any device or environment that can generate static electricity. The static electricity generated by the electrostatic source will enter the circuit to be protected inside the chip along with the conductor such as the pin, thereby affecting the normal operation of the circuit. The electrostatic impedance protection circuit provided in the embodiment of the present application is used in the circuit to be protected, and is used to eliminate the electrostatic interference generated by the electrostatic source, so as to protect the circuit to be protected.

[0042] The electrostatic impedance protection circuit provided in the embodiment of the present application adds an ESD voltage detection control circuit 200 compared to the traditional electrostatic protection circuit, which can control the second-level ESD circuit 300 to quickly discharge the ESD current according to the detected ESD voltage, thereby providing better electrostatic protection performance.

[0043] See also Figure 1 The embodiment of the present application provides an electrostatic impedance protection circuit 10, which at least includes: a multi-stage impedance protection circuit and a detection control circuit 200, wherein:

[0044] The multi-stage impedance protection circuits are cascaded with each other, the input end of the front-stage impedance protection circuit in the multi-stage impedance protection circuit is electrically connected to the static power source 20, and the last-stage impedance protection circuit in the multi-stage impedance protection circuit is electrically connected to the static power source 20 and the circuit to be protected 30 respectively.

[0045] Among them, the front-stage impedance protection circuit 100 refers to an impedance protection circuit electrically connected to the detection control circuit 200 and located at the front stage of the detection control circuit 200, and the rear-stage impedance protection circuit 300 refers to an impedance protection circuit electrically connected to the detection control circuit 200 and located at the rear stage of the detection control circuit 200. The front-most impedance protection circuit refers to an impedance protection circuit at the front end of a multi-stage impedance protection circuit, which is generally directly connected to the static power source 20, or is mutually inductive, or is the closest impedance protection circuit; the last-stage impedance protection circuit refers to an impedance protection circuit at the end of a multi-stage impedance protection circuit, which is generally directly connected to or is the closest impedance protection circuit to the circuit to be protected 30.

[0046] The working voltage or output voltage of the front-stage impedance protection circuit 100 is used as the control voltage of the rear-stage impedance protection circuit 300. For example, the multi-stage impedance protection circuit includes a first impedance protection circuit, a second impedance protection circuit and a third impedance protection circuit that are cascaded in sequence. Correspondingly, the working voltage or output voltage of the first impedance protection circuit is used as the control voltage of the second impedance protection circuit to control the working state of the second impedance protection circuit; the working voltage or output voltage of the second impedance protection circuit is used as the control voltage of the third impedance protection circuit to control the working state of the third impedance protection circuit.

[0047] At least one detection control circuit 200 is arranged between two adjacent levels of the impedance protection circuit. The detection control circuit 200 is used to detect the output voltage of the front-stage impedance protection circuit 100. The rear-stage impedance protection circuit 300 is started when the output voltage is greater than a preset voltage, and the electrostatic voltage Vesd of the electrostatic power source 20 is discharged; the detection control circuit 200 is used to detect the output voltage of the front-stage impedance protection circuit 100. The embodiment of the present application does not impose any limitation on the form of the detection control circuit 200, and it can be flexibly adjusted according to actual conditions, as long as it can realize the detection of the output voltage of the front-stage impedance protection circuit 100.

[0048] The electrostatic impedance protection circuit 10 provided in the embodiment of the present application includes a multi-stage impedance protection circuit, and at least one detection control circuit 200 is provided between two adjacent stages of impedance protection circuits, and the adjacent subsequent stage impedance protection circuit 300 can be controlled by the previous stage impedance protection circuit 100. In other words, the previous stage impedance protection circuit 100 performs a voltage reduction or a discharge on the electrostatic voltage Vesd generated by the electrostatic power source 20. If the electrostatic voltage Vesd after voltage reduction or discharge is less than or equal to the preset voltage, it means that the current limiting protection function of the previous stage impedance protection circuit 100 has eliminated the static electricity to a safe range, and will not affect or interfere with the circuit to be protected 30, so the subsequent stage impedance protection circuit 300 is in a closed state (non-working state), thereby reducing the overall energy consumption under the protection function;

[0049] Secondly, if the electrostatic voltage Vesd after voltage reduction or discharge is greater than the preset voltage, it means that the current limiting protection function of the front-stage impedance protection circuit 100 is not sufficient to eliminate the static electricity to a safe range, and the electrostatic voltage Vesd will still affect or interfere with the protection circuit 30. Therefore, the output voltage of the front-stage impedance protection circuit 100 is used as the control voltage of the rear-stage impedance protection circuit 300 to control the startup of the rear-stage impedance protection circuit 300. Since the rear-stage impedance protection circuit 300, or the last-stage impedance protection circuit is directly electrically connected to the electrostatic power source 20, the rear-stage impedance protection circuit 300 can directly discharge the electrostatic voltage Vesd of the electrostatic power source 20 quickly without going through the front-stage impedance protection circuit 100. , skipping the delay of the front-stage impedance protection circuit 100, and having a higher voltage reduction time efficiency; at the same time, the setting of the rear-stage impedance protection circuit 300 can effectively prevent the failure of the overall protection caused by the failure of the front-stage impedance protection circuit 100. Even if the rear-stage impedance protection circuit 300 fails completely, the front-stage impedance protection circuit 100 can also reduce the electrostatic voltage Vesd of the static power source 20 to a lower range, thereby minimizing the interference and influence on the circuit to be protected 30; in addition, the embodiment of the present application is provided with a multi-stage impedance protection circuit, which can minimize the influence of the static power source 20 on the circuit to be protected 30, and effectively prevent any one or several impedance protection circuits from failing without affecting the overall impedance protection effect;

[0050] In a third aspect, the embodiment of the present application includes a front-stage impedance protection circuit 100 and a rear-stage impedance protection circuit 300, and uses the output voltage of the front-stage impedance protection circuit 100 as the control voltage of the rear-stage impedance protection circuit 300 to control the startup of the rear-stage impedance protection circuit 300, and directly discharges the electrostatic voltage Vesd of the electrostatic source 20 quickly, so that a lower output ESD voltage can be achieved under the same ESD device size; correspondingly, when achieving the same ESD voltage, a smaller-sized ESD device can be selected, which greatly reduces the parasitic parameters of the ESD;

[0051] Fourthly, the embodiment of the present application includes a front-stage impedance protection circuit 100 and a rear-stage impedance protection circuit 300, and uses the output voltage of the front-stage impedance protection circuit 100 as the control voltage of the rear-stage impedance protection circuit 300 to control the startup of the rear-stage impedance protection circuit 300, and directly discharges the electrostatic voltage Vesd of the electrostatic source 20 quickly, without the need for the current limiting device 400 in the traditional solution to achieve the same or even better discharge effect, which greatly simplifies the circuit structure and reduces the circuit cost; Figure 3 and Figure 4 The effect simulation diagram of the conventional ESD circuit and the electrostatic impedance protection circuit 10 provided in the embodiment of the present application is shown as follows: Figure 3The figure shows a comparison of voltage simulation results of a conventional ESD circuit and the electrostatic impedance protection circuit 10 provided in the embodiment of the present application. It can be clearly seen that the Vesd1 (output voltage of the preceding stage impedance protection circuit 100) of the conventional ESD circuit and the electrostatic impedance protection circuit 10 provided in the embodiment of the present application are almost the same, but the Vesd2 (output voltage of the succeeding stage impedance protection circuit 300) of the electrostatic impedance protection circuit 10 provided in the embodiment of the present application is greatly reduced.

[0052] Figure 4 By comparing the simulation results of the ESD voltage Vesd (i.e., the overall output voltage of the electrostatic impedance protection circuit 10 provided in the present application) of the traditional ESD circuit and the electrostatic impedance protection circuit 10 provided in the embodiment of the present application, it can be seen that the ESD voltage of the electrostatic impedance protection circuit 10 provided in the embodiment of the present application is reduced by about 2.5V, which can significantly improve the ESD performance.

[0053] In summary, the embodiment of the present application provides an electrostatic impedance protection circuit 10 with a simple structure, lower cost, and the ability to achieve a lower ESD voltage.

[0054] Please continue to see Figure 2 In an optional embodiment of the present application, the front-stage impedance protection circuit 100 includes: a plurality of diode devices connected in series, for example Figure 2 D1 and D2 in .

[0055] In a circuit, when the voltage value that a diode is required to withstand exceeds its maximum reverse operating voltage, it is difficult for an ordinary diode to meet the requirement. In the embodiment of the present application, two or more diode devices are connected in series to replace a single diode device, so that each diode device shares the reverse voltage evenly and does not exceed its limit value. This can greatly improve the overall voltage resistance level, thereby improving the voltage resistance level of the electrostatic impedance protection circuit 10 in the embodiment of the present application.

[0056] See also Figure 5 In an optional embodiment of the present application, the front-stage impedance protection circuit 100 includes: a first diode module 110 and a second diode module 120 connected in parallel, the input ends of the first diode module 110 and the second diode module 120 are respectively electrically connected to the static power source 20, and the output ends of the first diode module 110 and the second diode module 120 are respectively grounded; wherein, the first diode module 110 and the second diode module 120 each include at least two diode devices connected in series, and the diode devices in the first diode module 110 and the diode devices in the second diode module 120 are connected in opposite directions. For example Figure 5The first diode module 110 includes diode devices D1 and D2. The first diode module 110 includes diode devices D3 and D4. D1 and D2 are forward connected, and D3 and D4 are reverse connected.

[0057] By connecting in parallel two first diode modules 110 and second diode modules 120 with opposite connection directions, the port voltage can be effectively clamped when positive and negative electrostatic voltages are generated. When the electrostatic voltage of the electrostatic source 20 is negative, the voltage stabilizing effect of the reversely connected second diode module 120 makes the voltage difference between the port and the ground no longer increase. When the electrostatic voltage of the electrostatic source 20 is positive, the voltage stabilizing effect of the forwardly connected first diode module 110 makes the voltage difference between the port and the ground no longer increase, thereby protecting the stability and safety of the overall circuit.

[0058] Please continue to see Figure 5 In an optional embodiment of the present application, the post-stage impedance protection circuit 300 at least includes: a transistor device M1, wherein:

[0059] The control end of the transistor device M1 is electrically connected to the detection control circuit 200, the first connection end of the transistor device M1 is electrically connected to the connection point between the front-stage impedance protection circuit 100 and the electrostatic source 20, the second connection end of the transistor device M1 is grounded, and the transistor device M1 is started when the operating voltage of the front-stage impedance protection circuit 100 is greater than the preset voltage, and discharges the electrostatic voltage Vesd of the electrostatic source 20.

[0060] The embodiment of the present application utilizes the switching characteristics of the transistor to start different working states under different output voltages through the transistor, so that the rear-stage impedance protection circuit 300 can switch to different working states under different output voltages under the action of the front-stage impedance protection circuit 100, thereby achieving the effect of electrostatic protection while reducing energy consumption.

[0061] Please continue to see Figure 5 In an optional embodiment of the present application, the transistor device M1 is an N-type transistor.

[0062] The N-type transistor is turned on under the action of a high level to achieve the purpose of current discharge, and is turned off under the action of a low level to achieve the effect of reducing energy consumption. For example, the N-type transistor can be a GGNMOS (Gate-Grounded NMOS, NMOS with the gate connected to the ground). The structure of the GGNMOS is compared with the ordinary NMOS structure. A certain distance is pulled between Drain and Gate, which is called DCG (i.e., the distance from drain contact to gate gate). There is also a certain size control between the source source and the gate gate, which is called SCG (i.e., the distance from source contact to gate gate);

[0063] GGNMOS is connected in parallel with the circuit to be protected 30. When the electrostatic voltage Vesd of the electrostatic source 20 is too large and the I / O has a large voltage, the Drian / bulk voltage exceeds its breakdown voltage, and avalanche breakdown is likely to occur, thereby causing device breakdown. In the embodiment of the present application, the detection control circuit 200 turns on the GGNMOS to ensure that all are turned on before the first device finally breaks down, thereby turning on the transistor and achieving the purpose of quickly discharging the electrostatic voltage Vesd, ensuring that the voltage of the circuit to be protected 30 is not too high, and improving the overall reliability and working stability of the electrostatic impedance protection circuit 10 in the embodiment of the present application.

[0064] Please continue to see Figure 5 In an optional embodiment of the present application, the detection control circuit 200 at least includes: a first resistor device R1 and a second resistor device R2, wherein:

[0065] The first end of the first resistor device R1 is electrically connected to the front-stage impedance protection circuit 100; the second resistor device R2, the first end of the second resistor device R2 is electrically connected to the second end of the first resistor device R1 and the control end of the rear-stage impedance protection circuit 300 respectively, and the second end of the second resistor device R2 is grounded.

[0066] In the embodiment of the present application, the output voltage of the front-stage impedance protection circuit 100 is detected by a circuit composed of a first resistor device R1 and a second resistor device R2. The use of the first resistor device R1 and the second resistor device R2 has a simple structure and ensures that M1 is in an off state during normal operation without affecting the normal working state of the circuit. By adjusting the ratio of the resistor R1 and the second resistor device R2, the turn-on voltage of M1 can be flexibly adapted to ensure that the transistor device M1 can be turned on normally when an electrostatic voltage occurs, thereby improving the working performance of the rear-stage impedance protection circuit 300.

[0067] See also Figure 6 In an optional embodiment of the present application, the electrostatic impedance protection circuit 10 further includes: a current limiting device 400, wherein:

[0068] The input end of the current limiting device 400 is electrically connected to the connection point of the front-stage impedance protection circuit 100 and the static power source 20 , and the output end of the current limiting device 400 is electrically connected to the first connection end of the rear-stage impedance protection circuit 300 .

[0069] The embodiment of the present application directly sets a current limiting device 400 in the front-stage impedance protection circuit 100 and the rear-stage impedance protection circuit 300, so as to limit the electrostatic voltage Vesd within a relatively stable range, so as to ensure that the rear-stage impedance protection circuit 300 can work normally, and prevent the instability of the rear-stage impedance protection circuit 300 due to excessive or unstable static electricity, thereby improving the stability and reliability of the electrostatic impedance protection circuit 10 provided in the embodiment of the present application.

[0070] Please continue to see Figure 6 In an optional embodiment of the present application, the current limiting device 400 includes a plurality of capacitor devices C1 connected in series.

[0071] Due to the characteristics of the capacitor device C1 that blocks direct current and passes alternating current as well as charging and discharging, the electrostatic charge generated by the electrostatic power source 20 can be stored and flow into the subsequent impedance protection circuit 300 after the voltage stabilizes, rather than flowing directly into the subsequent impedance protection circuit 300. This can avoid the occurrence of pulses, instability, etc. that may damage the normal operation of the subsequent impedance protection circuit 300, thereby improving the stability and reliability of the electrostatic impedance protection circuit 10 provided in the embodiment of the present application.

[0072] In an optional embodiment of the present application, the multi-stage impedance protection circuit is a two-stage impedance protection circuit.

[0073] That is, the front end of the detection control circuit 200 is connected to the front-stage impedance protection circuit, that is, the front-stage impedance protection circuit 100. Correspondingly, the back end of the detection control circuit 200 is connected to the final-stage impedance protection circuit, that is, the rear-stage impedance protection circuit 300. The electrostatic voltage Vesd is preliminarily discharged through the front-stage impedance protection circuit 100, and then the rear-stage impedance protection circuit 300 is controlled by the output voltage of the front-stage impedance protection circuit 100. The purpose of the above-mentioned fast discharge can be achieved through the simplest circuit structure. While achieving fast discharge, the circuit structure is further simplified, the device miniaturization is promoted, and the circuit cost is further reduced.

[0074] In an optional embodiment of the present application, the above-mentioned circuit to be protected is a radio frequency system circuit, which includes a low-noise amplifier circuit for amplifying a signal while maintaining the system, and the low-noise amplifier circuit at least includes: an amplifier input circuit and an amplifier output circuit; wherein, there is at least one group of tail inductance structures in the amplifier input circuit and the amplifier output circuit; a first resonant circuit, the first resonant circuit is a closed structure, the first resonant circuit is coupled to the tail inductance structure, and the first resonant circuit is used to discharge the current generated by the tail inductance structure; the first resonant circuit at least includes: a secondary coil, coupled to the primary coil in the tail inductance structure; a first capacitor module, the first end of the first capacitor module is electrically connected to the secondary coil.

[0075] In an optional embodiment of the present application, the first resonant circuit further includes: a first adjustable resistor, wherein the first end of the first adjustable resistor is electrically connected to the first end of the secondary coil, and the second end of the first adjustable resistor is electrically connected to the second end of the first capacitor module; wherein the secondary coil, the first capacitor module and the first adjustable resistor are electrically connected to each other to form a closed structure.

[0076] In an optional embodiment of the present application, the amplifying input circuit at least includes:

[0077] An electrostatic protection circuit, wherein an input end of the electrostatic protection circuit is used to receive a radio frequency signal to be amplified, and the electrostatic protection circuit is grounded;

[0078] A second capacitor module, wherein a first end of the second capacitor module is electrically connected to the output end of the electrostatic protection circuit, and a second end of the capacitor module is grounded;

[0079] A first transistor module, wherein the control end of the first transistor module is electrically connected to the second capacitor module and the bias voltage, the source end of the first transistor module is electrically connected to the amplifying output circuit, and the drain end of the first transistor module is electrically connected to the primary coil in the tail inductor structure.

[0080] In an optional embodiment of the present application, the first transistor module at least includes:

[0081] a first transistor device, wherein a gate of the first transistor device is electrically connected to the second capacitor module and a first bias voltage, and a drain of the first transistor device is electrically connected to the primary coil in the tail inductor structure;

[0082] A second transistor device, wherein the gate of the second transistor device is used to connect to a second bias voltage, the source of the second transistor device is electrically connected to the amplifying output circuit, and the drain of the second transistor device is electrically connected to the source of the first transistor device.

[0083] In an optional embodiment of the present application, the amplification output circuit at least includes:

[0084] a second transistor module, wherein a gate of the second transistor module is used to receive an enable signal, and a drain of the second transistor module is electrically connected to the second capacitor module;

[0085] a second resonant circuit, wherein an input end of the second resonant circuit is electrically connected to a source of the second crystal module;

[0086] An output matching circuit, wherein the input end of the output matching circuit is electrically connected to the output end of the second resonant circuit, and the output matching circuit is used to perform frequency matching and gain adjustment on the signal output by the second resonant circuit and then output a target radio frequency signal.

[0087] In an optional embodiment of the present application, the output matching circuit at least includes:

[0088] at least two groups of capacitors connected in parallel, wherein a first end of the capacitor is electrically connected to an output end of the second resonant circuit;

[0089] a first attenuation device, wherein an input end of the first attenuation device is electrically connected to the second end of the capacitor device, and the first attenuation device and the capacitor device perform frequency matching and gain adjustment on a signal output by the second resonant circuit to the target radio frequency signal;

[0090] An output module, wherein an input end of the output module is electrically connected to an output end of the first attenuation device, and the output module is used to output the target radio frequency signal.

[0091] In an optional embodiment of the present application, the above-mentioned low-noise amplifier circuit further includes: a second attenuation device, wherein the input end of the second attenuation device is electrically connected to the source of the second transistor module, and the output end of the second attenuation device is electrically connected to the second resonant device.

[0092] In an optional embodiment of the present application, the tail inductor structure in the amplifier input circuit at least includes:

[0093] The primary coil;

[0094] A plurality of third transistor modules, wherein the gates of the third transistor modules are used to receive control signals, the sources of the third transistor modules are respectively electrically connected to the primary coils, and the drains of the third transistors are grounded.

[0095] In an optional embodiment of the present application, the power supply of the front-stage impedance protection circuit is a dual power supply system, including an analog power supply and a digital circuit, wherein the analog power supply is used to provide the working current of the front-stage impedance protection circuit, and the digital power supply is powered on first to ensure that the control signal to the front-stage impedance protection circuit is in a certain state before the front-stage impedance protection circuit is powered on. A level shift unit, the input end of the level shift unit is electrically connected to the digital power supply, and the level shift unit is used to pull the digital power supply to a comparison voltage within a preset voltage range; the electrostatic impedance protection circuit also includes:

[0096] A level comparison output unit, wherein the input end of the level comparison output unit is electrically connected to the input end of the analog power supply and the level shift unit respectively, and the level comparison output unit is used to output a first control signal when the comparison voltage is greater than the analog voltage of the analog power supply, and output a second control signal when the comparison voltage is not greater than the analog voltage; wherein the first control signal controls the front-stage impedance protection circuit not to work, and the second control signal controls the front-stage impedance protection circuit to work.

[0097] In an optional embodiment of the present application, the level shift unit at least includes: a level shift module, an output end of the level shift module is electrically connected to an input end of the level comparison output unit;

[0098] A first transistor device, wherein a gate of the first transistor device is electrically connected to the digital power supply, a source of the first transistor device is electrically connected to an input end of the level shift module, and a drain of the first transistor is grounded.

[0099] In an optional embodiment of the present application, the level comparison output unit includes:

[0100] A level comparison module, wherein an input end of the level comparison module is electrically connected to an output end of the analog power supply and the level shift module respectively;

[0101] A comparison output module, wherein the control end of the comparison output module is electrically connected to the gate of the first transistor device, the input end of the comparison output module is electrically connected to the output end of the level comparison module, the first output end of the comparison output module is grounded, and the second output end of the comparison output module is used to output the first control signal or the second control signal.

[0102] In an optional embodiment of the present application, the level comparison module at least includes:

[0103] a second transistor device, wherein a gate and a drain of the second transistor device are electrically connected to an input terminal of the level shift module, and a source of the second transistor device is electrically connected to the analog power supply;

[0104] A third transistor device, wherein a gate of the third transistor device is electrically connected to the gate of the second transistor device, a source of the third transistor device is electrically connected to the analog power supply, and a drain of the third transistor device is electrically connected to the input end of the comparison output module.

[0105] In an optional embodiment of the present application, the comparison output module includes at least: a fourth transistor device and a fifth transistor device, wherein the gate of the fourth transistor device is electrically connected to the digital power supply, and the source of the fourth transistor device is electrically connected to the drain of the third transistor device; the gate of the fifth transistor device is electrically connected to the digital power supply, the source of the fifth transistor device is electrically connected to the drain of the fourth transistor device, and the drain of the fifth transistor device is grounded.

[0106] In an optional embodiment of the present application, the first transistor device, the second transistor device, the third transistor device and the fourth transistor device are all P-type transistor devices; the fifth transistor device is an N-type transistor device. The level shift module includes a plurality of transistors, each of which is formed by connecting a number of diodes that are not completely the same. The number of the transistors is positively correlated with the absolute value of the voltage difference between the digital power supply and the analog power supply.

[0107] An embodiment of the present application provides an electronic device, including:

[0108] A working circuit, wherein the working circuit generates static electricity when working;

[0109] As described in any of the above items, the input end of the electrostatic impedance protection circuit 10 is electrically connected to the working circuit, and the electrostatic impedance protection circuit 10 is started when the electrostatic voltage Vesd generated by the working circuit is greater than a preset voltage, and discharges the electrostatic voltage Vesd.

[0110] The beneficial effects of the electrostatic impedance protection circuit 10 have been described in detail in the above embodiments, and will not be repeated here. As described in the above embodiments, the embodiments of the present application provide an electronic device that can simultaneously meet the purposes of low energy consumption and rapid discharge of static electricity.

[0111] It should be understood that, although the various steps in the flow chart are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear description in this article, the execution of these steps is not strictly limited in order, and these steps can be executed in other orders. Moreover, at least a portion of the steps in the figure may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these sub-steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

[0112] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0113] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. An electrostatic impedance protection circuit, characterized in that: At least: A multi-stage impedance protection circuit, wherein at least one detection control circuit is provided between two adjacent stages of the impedance protection circuits, the input end of the first stage impedance protection circuit in the multi-stage impedance protection circuit is electrically connected to a static power source, and the last stage impedance protection circuit in the multi-stage impedance protection circuit is electrically connected to the static power source and the circuit to be protected, respectively; The detection control circuit is used to detect the output voltage of the front-stage impedance protection circuit, and the rear-stage impedance protection circuit is started when the output voltage is greater than a preset voltage, and discharges the electrostatic voltage of the electrostatic power source; wherein, the front-stage impedance protection circuit refers to an impedance protection circuit electrically connected to the detection control circuit and located at the front stage of the detection control circuit, and the rear-stage impedance protection circuit refers to an impedance protection circuit electrically connected to the detection control circuit and located at the rear stage of the detection control circuit.

2. The electrostatic impedance protection circuit according to claim 1, characterized in that: The front-stage impedance protection circuit includes: a plurality of diode devices connected in series.

3. The electrostatic impedance protection circuit according to claim 2, characterized in that: The front-stage impedance protection circuit comprises: A first diode module and a second diode module are connected in parallel, wherein the input ends of the first diode module and the second diode module are respectively electrically connected to the static power source, and the output ends of the first diode module and the second diode module are respectively grounded; wherein the first diode module and the second diode module respectively include at least two diode devices connected in series, and the connection direction of the diode device in the first diode module is opposite to that of the diode device in the second diode module.

4. The electrostatic impedance protection circuit according to claim 1, characterized in that: The post-stage impedance protection circuit at least comprises: A transistor device, wherein the control end of the transistor device is electrically connected to the detection control circuit, the first connection end of the transistor device is electrically connected to the connection point between the front-stage impedance protection circuit and the electrostatic power source, the second connection end of the transistor device is grounded, and the transistor device is started when the operating voltage of the front-stage impedance protection circuit is greater than a preset voltage, and discharges the electrostatic voltage of the electrostatic power source.

5. The electrostatic impedance protection circuit according to claim 4, characterized in that: The transistor device is an N-type transistor.

6. The electrostatic impedance protection circuit according to claim 1, characterized in that: The detection control circuit at least comprises: A first resistor device, wherein a first end of the first resistor device is electrically connected to the previous impedance protection circuit; A second resistor device, wherein a first end of the second resistor device is electrically connected to a second end of the first resistor device and a control end of the subsequent impedance protection circuit respectively, and a second end of the second resistor device is grounded.

7. The electrostatic impedance protection circuit according to claim 1, characterized in that: Also includes: A current limiting device, wherein the input end of the current limiting device is electrically connected to the connection point between the front-stage impedance protection circuit and the static power source, and the output end of the current limiting device is electrically connected to the first connection end of the rear-stage impedance protection circuit.

8. The electrostatic impedance protection circuit according to claim 7, characterized in that: The current limiting device includes a plurality of capacitor devices connected in series.

9. The electrostatic impedance protection circuit according to claim 1, characterized in that: The multi-stage impedance protection circuit is a two-stage impedance protection circuit.

10. An electronic device, characterized in that: include: A working circuit, wherein the working circuit generates static electricity when working; The electrostatic impedance protection circuit according to any one of claims 1 to 9, wherein the input end of the electrostatic impedance protection circuit is electrically connected to the working circuit, and the electrostatic impedance protection circuit is activated when the electrostatic voltage generated by the working circuit is greater than a preset voltage, and discharges the electrostatic voltage.

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