Electrostatic impedance protection circuit and electronic device

Abstract

The application 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 comprises at least: a multistage impedance protection circuit, at least one detection control circuit is arranged between two adjacent stages of the impedance protection circuit, an input end of the first-stage impedance protection circuit in the multistage impedance protection circuit is electrically connected with an electrostatic power supply, and the last-stage impedance protection circuit in the multistage impedance protection circuit is electrically connected with the electrostatic power supply and a circuit to be protected respectively; the detection control circuit is used for detecting an output voltage of the first-stage impedance protection circuit, a next-stage impedance protection circuit is started when the output voltage is greater than a preset voltage, and the electrostatic voltage of the electrostatic power supply is discharged. The electrostatic impedance protection circuit has the advantages of simple structure, lower cost and lower ESD 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] An ESD (electro-static discharge) circuit is essential for chip input / output (IO) circuits. Typically located near each pin within the chip, it absorbs static electricity introduced into the chip from the external environment through the pins, protecting the chip from certain ESD voltages. In RF and analog circuits, ESD circuits must have low parasitic parameters and be able to quickly discharge charge to prevent damage to the protected circuits caused by excessive voltage differences.

[0003] Traditional ESD circuits typically consist of two stages of protection circuits and current-limiting devices. During an ESD discharge, the voltage of the first-stage ESD protection circuit is higher, while after passing through the current-limiting device, the voltage of the second-stage ESD protection circuit is lower. While the first-stage ESD circuit discharges the current, the current-limiting device and the second-stage 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 must be connected in series, significantly increasing costs.

[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] A first aspect of an embodiment of the present application provides 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 a first-stage impedance protection circuit in the multi-stage impedance protection circuit is electrically connected to an electrostatic source, and a last-stage impedance protection circuit in the multi-stage impedance protection circuit is electrically connected to the electrostatic 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 comprises a plurality of diode devices connected in series.

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

[0010] a first diode module and a second diode module connected in parallel with each other, input ends of the first diode module and the second diode module being electrically connected to the electrostatic source, and output ends of the first diode module and the second diode module being grounded; wherein the first diode module and the second diode module each comprise at least two diode devices connected in series, and the diode devices in the first diode module and the second diode module are connected in opposite directions.

[0011] In an optional embodiment of the present application, the back-stage impedance protection circuit comprises at least:

[0012] a transistor device, a control end of the transistor device being electrically connected to the detection control circuit, a first connection end of the transistor device being electrically connected to the connection point of the front-stage impedance protection circuit and the electrostatic source, and a second connection end of the transistor device being grounded, the transistor device being activated when the working voltage of the front-stage impedance protection circuit is greater than a preset voltage, and discharging the electrostatic voltage of the electrostatic 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 comprises at least:

[0015] a first resistor device, a first end of the first resistor device being electrically connected to the front-stage impedance protection circuit;

[0016] a second resistor device, a first end of the second resistor device being electrically connected to a second end of the first resistor device and a control end of the back-stage impedance protection circuit respectively, and a second end of the second resistor device being grounded.

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

[0018] a current-limiting device, an input end of the current-limiting device being electrically connected to the connection point of the front-stage impedance protection circuit and the electrostatic source, and an output end of the current-limiting device being electrically connected to a first connection end of the back-stage impedance protection circuit.

[0019] In an optional embodiment of the present application, the current-limiting device comprises 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] In a second aspect of the embodiments of the present application, an electronic device is provided, comprising:

[0022] a working circuit, which generates static electricity when working;

[0023] The static electricity impedance protection circuit according to any one of the preceding embodiments, wherein an input end of the static electricity impedance protection circuit is electrically connected to the working circuit, and the static electricity impedance protection circuit is started when a static electricity voltage generated by the working circuit is greater than a preset voltage, and discharges the static electricity voltage.

[0024] The static electricity impedance protection circuit provided by the embodiments of the present application comprises a multi-stage impedance protection circuit, and at least one detection control circuit is arranged between adjacent two-stage impedance protection circuits, so that the adjacent next-stage impedance protection circuit can be controlled by the previous-stage impedance protection circuit. In other words, the previous-stage impedance protection circuit reduces the static electricity voltage generated by the static electricity source by one time or discharges the static electricity voltage by one time. If the static electricity voltage after the 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 protected circuit, so that the next-stage impedance protection circuit is in a closed state (non-working state), thereby reducing the overall energy consumption under the protection function;

[0025] In a second aspect, if the static electricity voltage after the 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 protected circuit, so that the output voltage of the previous-stage impedance protection circuit is used as the control voltage of the next-stage impedance protection circuit to control the next-stage impedance protection circuit to start. Since the next-stage impedance protection circuit, or the last-stage impedance protection circuit, is directly electrically connected to the static electricity source, the next-stage impedance protection circuit can directly discharge the static electricity voltage of the static electricity source quickly without passing through the previous-stage impedance protection circuit, thereby skipping the delay of the previous-stage impedance protection circuit and having a higher voltage reduction efficiency. At the same time, the arrangement of the next-stage impedance protection circuit can effectively prevent the failure of the previous-stage impedance protection circuit from causing the failure of the overall protection function. Even if the next-stage impedance protection circuit fails completely, the previous-stage impedance protection circuit can still reduce the static electricity voltage of the static electricity source to a lower range, thereby minimizing the interference and influence on the protected circuit. In addition, the multi-stage impedance protection circuit provided by the embodiments of the present application can minimize the influence of the static electricity source on the protected circuit, and effectively prevent the failure of any one or several impedance protection circuits from affecting the overall impedance protection effect;

[0026] In a third aspect, the embodiments of the present application include a front-stage impedance protection circuit and a back-stage impedance protection circuit, the output voltage of the front-stage impedance protection circuit is used as the control voltage of the back-stage impedance protection circuit to control the start of the back-stage impedance protection circuit, and the static voltage of the static source is directly and quickly discharged, so that a lower output ESD voltage can be realized under the same size of ESD device; correspondingly, a smaller size of ESD device can be selected when realizing the same ESD voltage, and the parasitic parameters of the ESD are greatly reduced;

[0027] In a fourth aspect, the embodiments of the present application include a front-stage impedance protection circuit and a back-stage impedance protection circuit, the output voltage of the front-stage impedance protection circuit is used as the control voltage of the back-stage impedance protection circuit to control the start of the back-stage impedance protection circuit, and the static voltage of the static source is directly and quickly discharged, so that the same or even better discharge effect can be realized without the current limiting device in the traditional scheme, the circuit structure is greatly simplified, and the circuit cost is reduced.

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

[0029] The accompanying drawings, which are included to provide a further understanding of the present application, constitute a part of the present application, the illustrative embodiments of the present application and the description thereof serve to explain the present application, and do not constitute improper limitations on the present application. In the drawings:

[0030] Figure 1 A static impedance protection circuit structure diagram provided by the embodiments of the present application;

[0031] Figure 2 A static impedance protection circuit structure diagram provided by the embodiments of the present application;

[0032] Figure 3 A voltage simulation result comparison diagram of the static impedance protection circuit 10 provided by the traditional ESD circuit and the embodiments of the present application;

[0033] Figure 4 An ESD voltage Vesd (i.e. the overall output voltage of the static impedance protection circuit 10 provided by the present application) simulation result comparison diagram of the static impedance protection circuit 10 provided by the traditional ESD circuit and the embodiments of the present application;

[0034] Figure 5 A static impedance protection circuit structure diagram provided by one embodiment of the present application;

[0035] Figure 6 A static impedance protection circuit structure diagram provided by one embodiment of the present application. Wherein:

[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, rear-stage impedance protection circuit; 400, current limiting device; 20, electrostatic source; 30, circuit to be protected. DETAILED DESCRIPTION

[0037] In the process of implementing the present application, the applicant finds that there is an urgent need for an ESD circuit that meets the purposes of low cost and fast discharge at the same time.

[0038] To solve the above problems, the present application provides an electrostatic impedance protection circuit and electronic device. In order to make the purpose, technical scheme and advantages of the present application more clear and explicit, the electrostatic impedance protection circuit and electronic device of the present application are further described in detail below through embodiments and in conjunction with the drawings. It should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.

[0039] The serial numbers of components in this paper, such as "first", "second", etc., are only used to distinguish the described objects, and do not have any sequence or technical meaning. And the "connection" and "coupling" in the present application, unless otherwise specified, include direct and indirect connection (coupling). In the description of the present application, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate the orientation or positional relationship shown in the drawings, and are only used to facilitate the description of the present application and simplify the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0040] In the present application, unless otherwise expressly specified and limited, the first feature is "on" or "under" the second feature, which can be direct contact between the first and second features, or indirect contact between the first and second features through an intermediate medium. Moreover, the first feature "above", "above" and "above" the second feature can be directly above or obliquely above the first feature, or only indicate that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "below" and "below" the second feature can be directly below or obliquely below the first feature, or only indicate that the horizontal height of the first feature is less than that of the second feature.

[0041] The electrostatic impedance protection circuit provided by the embodiments of the present application is applied to a circuit or electronic device containing an electrostatic source, which can be any circuit, electronic device or external environment, or any device or environment that can generate static electricity. Static electricity generated by the electrostatic source can enter the to-be-protected circuit inside the chip through a pin or other conductive body, thereby affecting the normal operation of the circuit. The electrostatic impedance protection circuit provided by the embodiments of the present application is used in the to-be-protected circuit, and is used to eliminate the static interference generated by the electrostatic source, thereby protecting the to-be-protected circuit.

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

[0043] Please refer to Figure 1 The electrostatic impedance protection circuit 10 provided by the embodiments of the present application at least includes: a multi-stage impedance protection circuit and a detection control circuit 200, wherein:

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

[0045] The first-stage impedance protection circuit 100 refers to the impedance protection circuit that is electrically connected with the detection control circuit 200 and located in the front stage of the detection control circuit 200, and the last-stage impedance protection circuit 300 refers to the impedance protection circuit that is electrically connected with the detection control circuit 200 and located in the rear stage of the detection control circuit 200. The first-stage impedance protection circuit refers to the impedance protection circuit at the most front end in the multi-stage impedance protection circuit, which is generally directly connected with the electrostatic source 20, or is in mutual induction, or is the impedance protection circuit closest to the electrostatic source 20. The last-stage impedance protection circuit refers to the impedance protection circuit at the most rear end in the multi-stage impedance protection circuit, which is generally directly connected with the to-be-protected circuit 30 or is the impedance protection circuit closest to the to-be-protected circuit 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 comprises a first impedance protection circuit, a second impedance protection circuit and a third impedance protection circuit connected in sequence, and 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 stages of the impedance protection circuits, and the detection control circuit 200 is used to detect the output voltage of the front-stage impedance protection circuit 100, and the rear-stage impedance protection circuit 300 is started when the output voltage is greater than a preset voltage, and the static voltage Vesd of the static source 20 is discharged; the detection control circuit 200 is used to detect the output voltage of the front-stage impedance protection circuit 100, and the form of the detection control circuit 200 is not limited in the embodiment, and can be adjusted flexibly according to the actual situation, as long as the detection of the output voltage of the front-stage impedance protection circuit 100 can be realized.

[0048] The static impedance protection circuit 10 provided by the embodiment comprises a multi-stage impedance protection circuit, and at least one detection control circuit 200 is arranged between two adjacent stages of the impedance protection circuits, so that the front-stage impedance protection circuit 100 can control the rear-stage impedance protection circuit 200. In other words, the front-stage impedance protection circuit 100 performs one-time voltage reduction or one-time discharge on the static voltage Vesd generated by the static source 20, and if the static voltage Vesd after the voltage reduction or discharge is less than or equal to a preset voltage, it means that the current limiting protection of the front-stage impedance protection circuit 100 has eliminated the static electricity to a safe range, and the rear-stage impedance protection circuit 300 is in a closed state (non-working state), so as to reduce the overall energy consumption under the protection effect.

[0049] In a second aspect, if the static voltage VESD after voltage reduction or discharge is greater than the preset voltage, it means that the current limiting protection of the front-stage impedance protection circuit 100 is insufficient to eliminate the static electricity to a safe range, and the static voltage VESD still affects or interferes with the circuit to be protected 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 rear-stage impedance protection circuit 300 to start. Since the rear-stage impedance protection circuit 300, or the last-stage impedance protection circuit, is directly electrically connected to the static source 20, the rear-stage impedance protection circuit 300 can directly discharge the static voltage VESD of the static source 20 quickly without passing through the front-stage impedance protection circuit 100, thereby skipping the delay of the front-stage impedance protection circuit 100 and achieving higher voltage reduction efficiency. At the same time, the setting of the rear-stage impedance protection circuit 300 can effectively prevent the failure of the front-stage impedance protection circuit 100 from causing the failure of the overall protection effect. Even if the rear-stage impedance protection circuit 300 fails completely, the front-stage impedance protection circuit 100 can still reduce the static voltage VESD of the static source 20 to a lower range, thereby minimizing the interference and influence on the circuit to be protected 30. In addition, the multiple-stage impedance protection circuit provided in the embodiment of the application can minimize the influence of the static source 20 on the circuit to be protected 30, and effectively prevent the failure of any one or several impedance protection circuits from affecting the overall impedance protection effect.

[0050] In a third aspect, the embodiment of the application includes the front-stage impedance protection circuit 100 and the rear-stage impedance protection circuit 300. 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 rear-stage impedance protection circuit 300 to start, thereby directly discharging the static voltage VESD of the static source 20 quickly. This can achieve a lower output ESD voltage under the same size of ESD device. Correspondingly, when achieving the same ESD voltage, a smaller size of ESD device can be selected, thereby greatly reducing the parasitic parameters of the ESD.

[0051] In a fourth aspect, the embodiment of the application includes the front-stage impedance protection circuit 100 and the rear-stage impedance protection circuit 300. 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 rear-stage impedance protection circuit 300 to start, thereby directly discharging the static voltage VESD of the static source 20 quickly. This can achieve the same or even better discharge effect without the current limiting device 400 in the traditional scheme, thereby greatly simplifying the circuit structure and reducing the circuit cost. Figure 3 and Figure 4 The effect simulation diagram of the static impedance protection circuit 10 provided by the traditional ESD circuit and the embodiment of the application is as follows: Figure 3The voltage simulation result comparison of the traditional ESD circuit and the static electricity impedance protection circuit 10 provided by the embodiment of the present application is shown. It can be clearly seen that the Vesd1 (the output voltage of the front-stage impedance protection circuit 100) of the traditional ESD circuit and the static electricity impedance protection circuit 10 provided by the embodiment of the present application is almost the same, but the Vesd2 (the output voltage of the back-stage impedance protection circuit 300) of the static electricity impedance protection circuit 10 provided by the embodiment of the present application is greatly reduced.

[0052] Figure 4 The ESD voltage Vesd (i.e. the overall output voltage of the static electricity impedance protection circuit 10 provided by the present application) simulation result comparison of the traditional ESD circuit and the static electricity impedance protection circuit 10 provided by the embodiment of the present application can be seen. The ESD voltage of the static electricity impedance protection circuit 10 provided by the embodiment of the present application is reduced by about 2.5V, which can obviously improve the ESD performance.

[0053] In summary, the static electricity impedance protection circuit 10 provided by the embodiment of the present application has simple structure, lower cost and can realize 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 comprises a plurality of series-connected diode devices, for example Figure 2 D1 and D2 in the above.

[0055] In the circuit, when the voltage value required to be borne by the diode exceeds its maximum reverse working voltage, an ordinary diode is difficult to meet the requirement. The embodiment of the present application connects two or more diode devices in series to replace one diode device, so that each diode device averagely shares the reverse voltage and does not exceed its limit value. The overall voltage withstand level can be greatly improved, thereby improving the pressure bearing level of the static electricity impedance protection circuit 10 provided by the embodiment of the present application.

[0056] Please see Figure 5 In an optional embodiment of the present application, the front-stage impedance protection circuit 100 comprises a first diode module 110 and a second diode module 120 connected in parallel with each other, the input ends of the first diode module 110 and the second diode module 120 are electrically connected with the static electricity source 20 respectively, and the output ends of the first diode module 110 and the second diode module 120 are grounded respectively; wherein the first diode module 110 and the second diode module 120 each comprise at least two series-connected diode devices, and the connection direction of the diode devices in the first diode module 110 is opposite to that of the diode devices in the second diode module 120. For example Figure 5The first diode module 110 in the first diode module 110 includes diode devices D1 and D2, and the first diode module 110 includes diode devices D3 and D4, D1 and D2 are connected in positive direction, and D3 and D4 are connected in reverse direction.

[0057] By connecting the first diode module 110 and the second diode module 120 in parallel, the port voltage can be effectively clamped when the positive and negative electrostatic voltage is generated. When the electrostatic voltage of the electrostatic source 20 is negative, the voltage stabilization effect of the reverse-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 stabilization effect of the positive-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 refer to Figure 5 In an optional embodiment of the present application, the later-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 with the detection control circuit 200, the first connection end of the transistor device M1 is electrically connected with the connection point of 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 working voltage of the front-stage impedance protection circuit 100 is greater than a 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, and realizes different working states under different output voltages through the transistor, so that the later-stage impedance protection circuit 300 can realize switching of different working states under different output voltages under the action of the front-stage impedance protection circuit 100, thereby realizing the electrostatic protection function under the condition of reducing energy consumption.

[0061] Please continue to refer to 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 discharge, and is turned off under the action of a low level to achieve the purpose of reducing energy consumption. For example, the N-type transistor can be a GGNMOS (Gate-Grounded NMOS). The structure of the GGNMOS is pulled apart from the ordinary NMOS structure by a certain distance between the Drain and the Gate, becoming a DCG (i.e., the distance between the Drain Contact and the Gate). The distance between the Source and the Gate is also controlled to a certain size, which is called an SCG (i.e., the distance between the Source Contact and the Gate).

[0063] The GGNMOS is connected in parallel with the to-be-protected circuit 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 the breakdown voltage, and avalanche breakdown is easily caused, thereby causing the breakdown of the device. In the embodiment of the application, the GGNMOS can be opened by the detection control circuit 200 to ensure that all the GGNMOS are opened before the first device is finally broken down, to achieve the opening of the transistor and the purpose of rapid discharge of the electrostatic voltage Vesd, so as to ensure that the voltage of the to-be-protected circuit 30 is not too high, and to improve the overall reliability and working stability of the electrostatic impedance protection circuit 10.

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

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

[0066] The embodiment of the application realizes the detection of the output voltage of the front-stage impedance protection circuit 100 by the circuit composed of the first resistance device R1 and the second resistance device R2. The first resistance device R1 and the second resistance device R2 have a simple structure, can ensure that M1 is in an off state in a normal working state, and do not affect the normal working state of the circuit. By adjusting the ratio of the resistance R1 and the second resistance device R2, the opening voltage of M1 can be flexibly adapted, so that the transistor device M1 can be normally opened when the electrostatic voltage occurs, to improve the working performance of the rear-stage impedance protection circuit 300.

[0067] Please refer to Figure 6 In an optional embodiment of the application, the above 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 with the connection point of the front-stage impedance protection circuit 100 and the electrostatic source 20, and the output end of the current-limiting device 400 is electrically connected with the first connection end of the rear-stage impedance protection circuit 300.

[0069] The embodiment of the present application can limit the electrostatic voltage Vesd in a relatively stable range by directly arranging the current-limiting device 400 between the front-stage impedance protection circuit 100 and the rear-stage impedance protection circuit 300, so as to ensure that the rear-stage impedance protection circuit 300 can work normally, prevent the rear-stage impedance protection circuit 300 from being unstable due to excessive or unstable electrostatic, and further improve the stability and reliability of the electrostatic impedance protection circuit 10 provided by 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 series-connected capacitor devices C1.

[0071] Due to the characteristics of the capacitor device C1 in blocking direct current and passing alternating current and charging and discharging, the electrostatic charge generated by the electrostatic source 20 can be stored and then flow into the rear-stage impedance protection circuit 300 after the voltage is stable, instead of directly flowing in, so as to avoid the occurrence of pulse, instability and other situations to damage the normal work of the rear-stage impedance protection circuit 300, and further improve the stability and reliability of the electrostatic impedance protection circuit 10 provided by 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] The front end connected with the detection control circuit 200 is the frontmost-stage impedance protection circuit, that is, the front-stage impedance protection circuit 100, and correspondingly, the rear end connected with the detection control circuit 200 is the last-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 output voltage of the front-stage impedance protection circuit 100 controls the rear-stage impedance protection circuit 300, so that the above-mentioned rapid discharge purpose can be achieved through the most simplified circuit structure, the circuit structure is further simplified while realizing rapid discharge, the device is promoted to be miniaturized, and the circuit cost is further reduced.

[0074] In an optional embodiment of the present application, the to-be-protected circuit is a radio frequency system circuit, and the radio frequency system circuit comprises a low noise amplifier circuit for amplifying a signal while maintaining a low noise of the system, and the low noise amplifier circuit at least comprises: an amplification input circuit and an amplification output circuit; wherein at least one set of tail inductance structures is arranged in the amplification input circuit and the amplification 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 for discharging a current generated by the tail inductance structure; the first resonant circuit at least comprises: a secondary coil, which is coupled to a primary coil in the tail inductance structure; and a first capacitor module, a 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 comprises: a first adjustable resistor, a first end of the first adjustable resistor is electrically connected to a first end of the secondary coil, and a second end of the first adjustable resistor is electrically connected to a 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 amplification input circuit at least comprises:

[0077] An electrostatic protection circuit, an input end of the electrostatic protection circuit is used for receiving a to-be-amplified radio frequency signal, and the electrostatic protection circuit is grounded.

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

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

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

[0081] A first transistor device, 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 inductance structure.

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

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

[0084] a second transistor module, a gate of the second transistor module being configured to receive an enable signal, a drain of the second transistor module being electrically connected with the second capacitor module;

[0085] a second resonant circuit, an input of the second resonant circuit being electrically connected with a source of the second crystal module;

[0086] an output matching circuit, an input of the output matching circuit being electrically connected with an output of the second resonant circuit, the output matching circuit being configured to output a target radio frequency signal after frequency matching and gain adjustment on a signal output by the second resonant circuit.

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

[0088] at least two groups of parallel capacitor devices, a first end of the capacitor device being electrically connected with the output of the second resonant circuit;

[0089] a first attenuation device, an input of the first attenuation device being electrically connected with a second end of the capacitor device, the first attenuation device and the capacitor device being configured to frequency match and gain adjust the signal output by the second resonant circuit to the target radio frequency signal;

[0090] an output module, an input of the output module being electrically connected with an output of the first attenuation device, the output module being configured to output the target radio frequency signal.

[0091] In an optional embodiment of the present application, the low-noise amplification circuit further comprises: a second attenuation device, an input of the second attenuation device being electrically connected with the source of the second transistor module, an output of the second attenuation device being electrically connected with the second resonant device.

[0092] In an optional embodiment of the present application, the tail inductance structure in the amplification input circuit at least comprises:

[0093] the main-stage coil;

[0094] a plurality of third transistor modules, a gate of the third transistor module being configured to receive a control signal, a source of the third transistor module being electrically connected with the main-stage coil respectively, a drain of the third transistor being 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 power supply, wherein the analog power supply is configured to provide working current for the front-stage impedance protection circuit, the digital power supply is powered first to ensure that the control signal of the front-stage impedance protection circuit is in a determined state before the front-stage impedance protection circuit is powered. A level shift unit, an input end of the level shift unit is electrically connected with the digital power supply, and the level shift unit is configured to pull up the digital power supply to a comparison voltage in a preset voltage range; the static impedance protection circuit further comprises:

[0096] A level comparison output unit, input ends of the level comparison output unit are electrically connected with the input ends of the analog power supply and the level shift unit, respectively, and the level comparison output unit is configured to output a first control signal when the comparison voltage is greater than an 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 to not 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 comprises: a level shift module, an output end of the level shift module is electrically connected with an input end of the level comparison output unit;

[0098] A first transistor device, a gate of the first transistor device is electrically connected with the digital power supply, a source of the first transistor device is electrically connected with 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 comprises:

[0100] A level comparison module, input ends of the level comparison module are electrically connected with the analog power supply and an output end of the level shift module, respectively;

[0101] A comparison output module, a control end of the comparison output module is electrically connected with the gate of the first transistor device, an input end of the comparison output module is electrically connected with an output end of the level comparison module, a first output end of the comparison output module is grounded, and a second output end of the comparison output module is configured 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 comprises:

[0103] A second transistor device, a gate and a drain of the second transistor device are electrically connected with the input end of the level shift module, and a source of the second transistor device is electrically connected with the analog power supply;

[0104] a third transistor device, a gate of the third transistor device being electrically connected with the gate of the second transistor device, a source of the third transistor device being electrically connected with the analog power supply, and a drain of the third transistor device being electrically connected with an input terminal of the comparison output module.

[0105] In an optional embodiment of the present application, the comparison output module at least includes a fourth transistor device and a fifth transistor device, wherein a gate of the fourth transistor device is electrically connected with the digital power supply, a source of the fourth transistor device is electrically connected with the drain of the third transistor device; a gate of the fifth transistor device is electrically connected with the digital power supply, a source of the fifth transistor device is electrically connected with the drain of the fourth transistor device, and a 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; and the fifth transistor device is an N-type transistor device. The level shift module includes a plurality of transistors, each transistor being composed of a number of diode connections which are not completely 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, comprising:

[0108] a working circuit, the working circuit generating static electricity when working;

[0109] The static electricity impedance protection circuit 10 as any one of the above embodiments, an input terminal of the static electricity impedance protection circuit 10 being electrically connected with the working circuit, the static electricity impedance protection circuit 10 being started when the static voltage Vesd generated by the working circuit is greater than a preset voltage, and the static voltage Vesd being discharged.

[0110] The beneficial effects of the static electricity 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 which can simultaneously satisfy low energy consumption and rapid discharge of static electricity.

[0111] It should be understood that, although the steps in the flowchart are shown in a sequential order, the steps are not necessarily performed in the order shown by the arrows. Unless explicitly stated otherwise, the steps can be performed in any order, and the steps can be performed in other sequences. Moreover, at least some of the steps in the diagram can include multiple sub-steps or multiple stages, which are not necessarily performed at the same time, but can be performed at different times, and the order of the sub-steps or stages can not be sequential, but can be round-robin or alternating with at least some of the other steps or sub-steps or stages of other steps.

[0112] The technical features of the above-described embodiments can be combined in any manner. For brevity, not all possible combinations of the technical features in the above-described embodiments are described, but it should be understood that any combination of the technical features is within the scope of the present disclosure as long as there is no contradiction.

[0113] The above-described embodiments are merely representative of several embodiments of the present application, and the description is relatively specific and detailed, but should not be construed as limiting the scope of the patent application. It should be noted that, for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present application, and these are within the scope of the present application. Therefore, the scope of the patent of the present application should be subject to the appended 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 the 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. The rear-stage impedance protection circuit is activated when the output voltage is greater than a preset voltage and discharges the electrostatic voltage of the electrostatic source. 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. The front-stage impedance protection circuit includes: 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 electrostatic 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 each include at least two diode devices connected in series, and the diode devices in the first diode module are connected in opposite directions to the diode devices in the second diode module, so as to clamp the port voltage when positive and negative electrostatic voltages are generated.

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

3. The electrostatic impedance protection circuit according to claim 1, wherein: The post-stage impedance protection circuit at least includes: A transistor device, wherein a control end of the transistor device is electrically connected to the detection control circuit, a first connection end of the transistor device is electrically connected to a connection point between the preceding-stage impedance protection circuit and the electrostatic source, a second connection end of the transistor device is grounded, and the transistor device is activated when the operating voltage of the preceding-stage impedance protection circuit is greater than a preset voltage, and discharges the electrostatic voltage of the electrostatic source.

4. The electrostatic impedance protection circuit according to claim 3, characterized in that: The transistor device is an N-type transistor.

5. The electrostatic impedance protection circuit according to claim 1, wherein: The detection control circuit at least includes: a first resistor component, wherein a first end of the first resistor component is electrically connected to the front-stage impedance protection circuit; A second resistor device, wherein a first end of the second resistor device is electrically connected to the second end of the first resistor device and the control end of the subsequent impedance protection circuit respectively, and a second end of the second resistor device is grounded.

6. The electrostatic impedance protection circuit according to claim 1, wherein: Also includes: A current limiting device, wherein the input end of the current limiting device is electrically connected to the connection point of 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.

7. The electrostatic impedance protection circuit according to claim 6, characterized in that: The current limiting device includes a plurality of capacitor devices connected in series.

8. The electrostatic impedance protection circuit according to claim 1, wherein: The multi-stage impedance protection circuit is a two-stage impedance protection circuit.

9. An electronic device, characterized in that: include: a working circuit, wherein the working circuit generates static electricity when in operation; The electrostatic impedance protection circuit according to any one of claims 1 to 8, wherein an 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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