Electrostatic protection circuit and chip

Abstract

The invention discloses an electrostatic protection circuit and a chip. The electrostatic protection circuit comprises an anti-disturbance module, a dynamic electrostatic discharge module, a power supply end and a grounding end, the anti-disturbance module and the dynamic electrostatic discharge module are connected in series between the power supply end and the grounding end; wherein the dynamic electrostatic discharge module is configured to control the conduction state of the power supply end and the grounding end according to the change rate of the voltage transmitted to the dynamic electrostatic discharge module by the power supply end; the anti-disturbance module is configured to reduce the change rate of the voltage transmitted from the power supply end to the dynamic electrostatic discharge module. The problem of false triggering of the electrostatic protection circuit can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of electrostatic protection, and in particular to an electrostatic protection circuit and a chip. Background Art

[0002] ESD (Electro-Static discharge) is an important factor in chip failure. Therefore, ESD protection for chips is becoming increasingly important.

[0003] In the related art, RC_clamp can be used for ESD protection. Among them, RC_clamp can detect the energy pulse change, that is, the voltage change rate. If the energy pulse changes greatly, RC_clamp is turned on to discharge static electricity; if the energy pulse changes slightly, RC_clamp is turned off.

[0004] However, when the voltage jitter (Glitch) between the power supply and the ground is large, the RC_clamp may be triggered by mistake, thereby affecting the normal operation of the subsequent circuit. Summary of the invention

[0005] The present invention provides an electrostatic protection circuit and a chip to improve the problem of false triggering of the electrostatic protection circuit.

[0006] According to one aspect of the present invention, an electrostatic protection circuit comprises:

[0007] Anti-disturbance module, dynamic electrostatic discharge module, power supply terminal and grounding terminal;

[0008] The anti-disturbance module and the dynamic electrostatic discharge module are connected in series between the power supply end and the ground end; wherein, the dynamic electrostatic discharge module is configured to control the conduction state of the power supply end and the ground end according to the change rate of the voltage transmitted from the power supply end to the dynamic electrostatic discharge module; the anti-disturbance module is configured to reduce the change rate of the voltage transmitted from the power supply end to the dynamic electrostatic discharge module.

[0009] Optionally, the first end of the anti-disturbance module is electrically connected to the power supply end, the second end of the anti-disturbance module is electrically connected to the first end of the dynamic electrostatic discharge module, and the second end of the dynamic electrostatic discharge module is electrically connected to the ground end;

[0010] Alternatively, the first end of the dynamic electrostatic discharge module is electrically connected to the power supply end, the second end of the dynamic electrostatic discharge module is electrically connected to the first end of the anti-disturbance module, and the second end of the anti-disturbance module is electrically connected to the ground end.

[0011] Optionally, the anti-disturbance module comprises n voltage clamping units connected in series between a first end of the anti-disturbance module and a second end of the anti-disturbance module, and the voltage clamping units are configured to have a fixed voltage drop when turned on; n≥1, where n is an integer.

[0012] Optionally, n≥2; at least two of the clamping units have different circuit structures;

[0013] Alternatively, the circuit structures of all the clamping units are the same.

[0014] Optionally, the voltage clamping unit includes at least one of a diode, a Zener diode, a GGNMOS, a PNP transistor, an NPN transistor and a silicon controlled rectifier.

[0015] Optionally, the dynamic electrostatic discharge module includes:

[0016] A detection unit, wherein a first end of the detection unit is electrically connected to a first end of the dynamic electrostatic discharge module, a second end of the detection unit is electrically connected to a second end of the dynamic electrostatic discharge module, and the detection unit is configured to output a first voltage signal or a second voltage signal from an output end of the detection unit according to a rate of change of a voltage at the first end thereof;

[0017] a trigger unit, wherein a first end of the trigger unit is electrically connected to a first end of the dynamic electrostatic discharge module, a second end of the trigger unit is electrically connected to the ground end, and a control end of the trigger unit is electrically connected to an output end of the detection unit; the trigger unit is configured to output an on signal at the output end of the trigger unit according to the first voltage signal, and output an off signal at the output end of the trigger unit according to the second voltage signal;

[0018] A clamping unit, wherein the first end of the clamping unit is electrically connected to the first end of the dynamic electrostatic discharge module, the second end of the clamping unit is electrically connected to the second end of the dynamic electrostatic discharge module, and the control end of the clamping unit is electrically connected to the output end of the trigger unit; the clamping unit is configured to conduct the first end with its second end according to the conduction signal, and to disconnect the first end with its second end according to the shutdown signal.

[0019] Optionally, the detection unit includes a first resistor and a detection capacitor, the first resistor and the detection capacitor are connected in series between a first end of the detection unit and a second end of the detection unit; a common connection end of the first resistor and the detection capacitor is electrically connected to an output end of the detection unit.

[0020] Optionally, the trigger unit includes a first transistor and a second resistor; the control end of the first transistor is electrically connected to the control end of the trigger unit; the first end of the first transistor is electrically connected to the first end of the trigger unit, the second end of the first transistor is electrically connected to the first end of the second resistor, and the second end of the second resistor is electrically connected to the second end of the trigger unit;

[0021] Alternatively, the trigger unit includes a first transistor and a second transistor connected in sequence between the first end of the trigger unit and the second end of the trigger unit; the control end of the first transistor and the control end of the second transistor are both electrically connected to the control end of the trigger unit; the first transistor is a P-channel transistor, and the second transistor is an N-channel transistor.

[0022] Optionally, the clamping unit includes a third transistor, a first end of the third transistor is electrically connected to the first end of the clamping unit, a second end of the third transistor is electrically connected to the second end of the clamping unit, and a control end of the third transistor is electrically connected to the control end of the clamping unit.

[0023] According to another aspect of the present invention, a chip is provided, wherein the chip includes the electrostatic protection circuit as described above.

[0024] The technical solution of the embodiment of the present invention adopts an electrostatic protection circuit including an anti-disturbance module, a dynamic electrostatic discharge module, a power supply terminal and a ground terminal; the anti-disturbance module and the dynamic electrostatic discharge module are connected in series between the power supply terminal and the ground terminal; wherein the dynamic electrostatic discharge module is configured to control the conduction state of the power supply terminal and the ground terminal according to the change rate of the voltage transmitted from the power supply terminal to the dynamic electrostatic discharge module; the anti-disturbance module is configured to reduce the change rate of the voltage transmitted from the power supply terminal to the dynamic electrostatic discharge module. By setting the anti-disturbance module, the change rate of the voltage transmitted to the dynamic electrostatic discharge module becomes smaller, so that the voltage disturbance between the power supply terminal and the ground terminal will not trigger the dynamic electrostatic discharge module, thereby greatly improving the false triggering problem of the electrostatic protection circuit.

[0025] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0027] Figure 1 A schematic diagram of a circuit structure of an electrostatic protection circuit provided by an embodiment of the present invention;

[0028] Figure 2 A schematic diagram of a circuit structure of another electrostatic protection circuit provided in an embodiment of the present invention;

[0029] Figure 3 A schematic diagram of a circuit structure of an anti-disturbance module provided in an embodiment of the present invention;

[0030] Figures 4 to 11 Schematic diagrams of various circuit structures of the anti-disturbance module provided in the embodiments of the present invention;

[0031] Fig.12 A schematic diagram of the circuit structure of a dynamic electrostatic discharge module provided in an embodiment of the present invention;

[0032] Fig.13 A schematic diagram of a circuit structure of a detection unit provided in an embodiment of the present invention;

[0033] Fig.14 A schematic diagram of a circuit structure of another detection unit provided in an embodiment of the present invention;

[0034] Fig.15 A schematic diagram of a circuit structure of a trigger unit provided in an embodiment of the present invention;

[0035] Fig.16 A schematic diagram of a circuit structure of another trigger unit provided in an embodiment of the present invention;

[0036] Fig.17 A schematic diagram of a circuit structure of another trigger unit provided in an embodiment of the present invention;

[0037] Fig.18 A schematic diagram of a circuit structure of a clamping unit provided in an embodiment of the present invention;

[0038] Fig.19 A schematic diagram of a circuit structure of another electrostatic protection circuit provided in an embodiment of the present invention;

[0039] Fig. 20 A schematic diagram of the circuit structure of another electrostatic protection circuit provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0040] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0041] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0042] Figure 1 A schematic diagram of a circuit structure of an electrostatic protection circuit provided by an embodiment of the present invention, referring to Figure 1 , the electrostatic protection circuit includes: an anti-disturbance module 11, a dynamic electrostatic discharge module 12, a power supply terminal Power and a ground terminal GND. The anti-disturbance module 11 and the dynamic electrostatic discharge module 12 are connected in series between the power supply terminal Power and the ground terminal GND; wherein the dynamic electrostatic discharge module 12 is configured to control the conduction state of the power supply terminal Power and the ground terminal GND according to the change rate of the voltage transmitted from the power supply terminal Power to the dynamic electrostatic discharge module 12; the anti-disturbance module 11 is configured to reduce the change rate of the voltage transmitted from the power supply terminal Power to the dynamic electrostatic discharge module 12.

[0043] Specifically, the electrostatic protection circuit can be applied to the circuit to be protected, for example, it can be applied to the chip. The power terminal Power of the electrostatic protection circuit is the power terminal of the circuit to be protected, and the ground terminal GND of the electrostatic protection circuit is the ground terminal of the circuit to be protected. In other words, the electrostatic protection circuit is used to prevent the static electricity between the power terminal and the ground terminal of the circuit to be protected from affecting the circuit to be protected.

[0044] The electrostatic voltage between the power terminal Power and the ground terminal GND has a faster rate of change, that is, at this time, the dv1 / dt between the power terminal Power and the ground terminal GND is large, where dv1 is the difference in potential between the power terminal Power and the ground terminal GND within the dt time. When the rate of change dv1 / dt of the voltage between the power terminal Power and the ground terminal GND is large, the dynamic electrostatic discharge module 12 is turned on, thereby transmitting the static electricity on the power terminal Power to the ground terminal GND, preventing the static electricity from affecting the subsequent circuit to be protected.

[0045] When the circuit to be protected is powered on normally, the rate of change of the voltage between the power terminal Power and the ground terminal GND is small, that is, dv1 / dt is small. At this time, the dynamic electrostatic discharge module 12 is turned off, that is, the electrostatic protection circuit is equivalent to an open circuit, and no short circuit will occur between the power terminal Power and the ground terminal GND, so that the subsequent circuit to be protected can work normally.

[0046] In some current implementations, for example, when the disturbance of the circuit to be protected is large, or it can also be understood as large jitter (Glitch), the circuit to be protected is, for example, a high-power drive circuit and a high-noise circuit. The voltage disturbance between the power terminal Power and the ground terminal GND of the circuit to be protected is large, that is, although the voltage change rate between the power terminal Power and the ground terminal GND corresponding to the voltage disturbance is smaller than the voltage change rate between the power terminal Power and the ground terminal GND corresponding to static electricity, it will still turn on the dynamic static discharge module 12, that is, the static protection circuit has a false triggering phenomenon, so that when the circuit to be protected is working normally, the power terminal Power and the ground terminal GND are short-circuited, thereby damaging the circuit to be protected.

[0047] In the present embodiment, by connecting the anti-disturbance module 11 and the dynamic electrostatic discharge module 12 in series, the anti-disturbance module 11 can reduce the rate of change of the voltage transmitted from the power supply terminal Power to the dynamic electrostatic discharge module 12. Thus, the rate of change of the voltage received by the dynamic electrostatic discharge module 12 becomes smaller, that is, the rate of change of the voltage at both ends of the dynamic electrostatic discharge module 12 (dv2 / dt) is less than the rate of change of the voltage between the power supply terminal Power and the ground terminal (dv1 / dt). In other words, when the disturbance of the voltage between the power supply terminal Power and the ground terminal GND is large, due to the setting of the anti-disturbance module 11, the rate of change of the voltage received by the dynamic electrostatic discharge module 12 becomes smaller, and the dynamic electrostatic discharge module 12 remains in the off state, thereby avoiding the dynamic electrostatic discharge module 12 from being triggered incorrectly.

[0048] Of course, it should be noted that for the static electricity at the power supply end Power, the corresponding voltage change rate (dv1 / dt) is relatively large. Even after being processed by the anti-disturbance module 11, the change rate (dv2 / dt) of the voltage transmitted to the dynamic electrostatic discharge module 12 is still relatively large, which means that the electrostatic protection circuit can effectively identify static electricity. During normal power-on, the dv1 / dt corresponding to the normal power-on voltage is relatively small. After being processed by the anti-disturbance module 11, the change rate (dv2 / dt) of the voltage transmitted to the dynamic electrostatic discharge module 12 is even smaller, so that the dynamic electrostatic discharge module 12 is turned off, and the circuit to be protected can be powered on normally. In summary, the electrostatic protection circuit of this embodiment can effectively identify static electricity, voltage disturbances and normal power-on, and will not be triggered during voltage disturbances, that is, the probability of false triggering is relatively small.

[0049] The technical solution of this embodiment adopts an electrostatic protection circuit including an anti-disturbance module, a dynamic electrostatic discharge module, a power supply terminal and a ground terminal; the anti-disturbance module and the dynamic electrostatic discharge module are connected in series between the power supply terminal and the ground terminal; wherein the dynamic electrostatic discharge module is configured to control the conduction state of the power supply terminal and the ground terminal according to the change rate of the voltage transmitted from the power supply terminal to the dynamic electrostatic discharge module; the anti-disturbance module is configured to reduce the change rate of the voltage transmitted from the power supply terminal to the dynamic electrostatic discharge module. That is, by setting the anti-disturbance module, the change rate of the voltage transmitted to the dynamic electrostatic discharge module becomes smaller, and then the voltage disturbance between the power supply terminal and the ground terminal will not erroneously trigger the dynamic electrostatic discharge module, thereby greatly improving the false triggering problem of the electrostatic protection circuit.

[0050] It should be noted that the dynamic electrostatic discharge module 12 is an electrostatic protection structure triggered according to the rate of change of the voltage, which can have a lower trigger voltage and clamping voltage, so that the circuit to be protected can be effectively protected. In addition, there is no need to use feedback or other forms to reduce the risk of false triggering, so there is no need for precise feedback control, and it will not affect the discharge of electrostatic pulses. The dynamic electrostatic discharge module 12 and the anti-disturbance module 11 are connected in series. Compared with the electrostatic protection structure that integrates the anti-disturbance module 11 into the dynamic electrostatic discharge module 12, the parameter design of the dynamic electrostatic discharge module 12 is easier.

[0051] Optionally, refer to Figure 1 The first end a of the anti-disturbance module 11 is electrically connected to the power end Power, the second end b of the anti-disturbance module 11 is electrically connected to the first end c of the dynamic electrostatic discharge module 12, and the second end d of the dynamic electrostatic discharge module 12 is electrically connected to the ground end GND.

[0052] Specifically, in this embodiment, when the voltage at the power terminal Power is large enough to turn on the anti-disturbance module 11, the change rate of the voltage at the power terminal Power is reduced after passing through the anti-disturbance module 11 and is then loaded to the first terminal c of the dynamic electrostatic discharge module 12.

[0053] Optionally, Figure 2 A schematic diagram of the circuit structure of another electrostatic protection circuit provided by an embodiment of the present invention. Figure 2 The first end c of the dynamic electrostatic discharge module 12 is electrically connected to the power end Power, the second end d of the dynamic electrostatic discharge module 12 is electrically connected to the first end a of the anti-disturbance module 11, and the second end b of the anti-disturbance module 11 is electrically connected to the ground end GND.

[0054] Specifically, in this embodiment, the anti-disturbance module 11 reduces the voltage between the first end and the second end of the dynamic electrostatic discharge module 12, thereby reducing the rate of change of the voltage at the first end a of the dynamic electrostatic discharge module 12, thereby reducing the probability of false triggering of the electrostatic protection circuit.

[0055] Optionally, refer to Figure 3 , Figure 3 A schematic diagram of the circuit structure of an anti-disturbance module provided in an embodiment of the present invention. The anti-disturbance module 11 includes n clamping units 11A connected in series between a first end a of the anti-disturbance module 11 and a second end b of the anti-disturbance module 11, and the clamping unit 11A is configured to have a fixed voltage drop when turned on; n≥1, where n is an integer.

[0056] Specifically, among the n clamping units 11A, the first end of the first-stage clamping unit 11A(1) is electrically connected to the first end a of the anti-disturbance module 11; when the second end of the current-stage clamping unit 11A(i) is electrically connected to the first end of the next-stage clamping unit 11A(i+1), 1<i<n, i is an integer; the second end of the last-stage clamping unit 11A(n) is electrically connected to the second end b of the anti-disturbance module 11. When the clamping unit 11A is turned on, there is a fixed voltage drop between its first end and the second end. That is, if the voltage at the first end of the clamping unit 11A is Va, then when the clamping unit 11A is turned on, the voltage at the second end is Va-Vth, where Vth is the inherent voltage drop of the clamping unit 11A. When the rate of change of the voltage at the power supply end Power is dv1 / dt, by setting n clamping units, the rate of change of the voltage at the first end of the dynamic electrostatic discharge module 12 is (dv1-n*Vth) / dt. It can be seen that, in this embodiment, the function of reducing the rate of change of the voltage at the power supply end of the anti-disturbance module 11 can be achieved by providing n voltage clamping units 11A.

[0057] Optionally, the voltage clamping unit includes at least one of a diode, a Zener diode, a GGNMOS, a PNP transistor, an NPN transistor and a silicon controlled rectifier (SCR).

[0058] In some embodiments, n≥2, and the circuit structures of all the clamping units are the same, that is, all the clamping units are diodes, Zener diodes, GGNMOS, PNP transistors, NPN transistors, or silicon controlled rectifiers.

[0059] Specifically, Figures 4 to 9 Schematic diagram of various circuit structures of the anti-disturbance module provided by the embodiment of the present invention. Figure 4 In this embodiment, all the clamping units are diodes 111, and the anode of the diode 111 serves as the first end of the clamping unit, and the cathode of the diode 111 serves as the second end of the clamping unit. Figure 5 In this embodiment, all the clamping units are Zener tubes 112, the cathode of the Zener tube 112 serves as the first end of the clamping unit, and the anode of the Zener tube 112 serves as the second end of the clamping unit. Figure 6 In this embodiment, all the clamping units are GGNMOS113, that is, NMOS with gate and source connected, wherein the drain of the NMOS serves as the first end of the clamping unit, and the source of the NMOS serves as the second end of the clamping unit. Figure 7 In this embodiment, all the clamping units are PNP transistors 114, the base and emitter of the PNP transistors are electrically connected, wherein the collector of the PNP transistor serves as the first end of the clamping unit, and the emitter of the PNP transistor serves as the second end of the clamping unit. Figure 8 In this embodiment, all the clamping units are NPN transistors 115, the base and emitter of the NPN transistor are electrically connected, wherein the collector of the NPN transistor serves as the first end of the clamping unit, and the emitter of the NPN transistor serves as the second end of the clamping unit. Fig. 9 In this embodiment, all the clamping units are silicon controlled rectifiers SCR 116 .

[0060] In this embodiment, the circuit structures of all the clamping units are set to be the same, so that the circuit structure of the anti-disturbance module 11 is simple, the types of components in the electrostatic protection circuit are relatively small, and the cost of the electrostatic protection circuit can be reduced. In addition, the consistency of the components in the anti-disturbance module 11 is high, and the stability of the anti-disturbance module 11 is also higher.

[0061] Optionally, in some other embodiments, at least two clamping units with different circuit structures may be provided. For example, the anti-disturbance module 11 may be composed of at least two of a diode, a Zener tube, a GGNMOS, a PNP transistor, an NPN transistor and a thyristor rectifier connected in series. In other words, the specific circuit structure of the anti-disturbance module 11 may be determined according to the range of the voltage disturbance at the power supply end, so that the voltage disturbance can reduce the rate of change of the voltage to a range that does not trigger the dynamic electrostatic discharge module 12 after passing through the anti-disturbance module 11.

[0062] Specifically, Fig.10 and Fig.11 Schematic diagram of various circuit structures of the anti-disturbance module provided by the embodiment of the present invention. Fig.10 The anti-disturbance module 11 can be composed of a diode and a Zener tube, that is, a Zener tube can be used to replace multiple diodes, so that the number of components in the anti-disturbance module 11 is small, which is conducive to reducing the volume of the anti-disturbance module 11. Fig.11 The anti-disturbance module 11 can be composed of a GGNMOS and a thyristor rectifier.

[0063] It should be noted that Fig.10 and Fig.11 There is no limitation on the number and series connection sequence of the clamping units with different circuit structures.

[0064] Optionally, Fig.12 A schematic diagram of the circuit structure of a dynamic electrostatic discharge module provided by an embodiment of the present invention. Fig.12 The dynamic electrostatic discharge module 12 includes a detection unit 121 , a trigger unit 122 and a clamping unit 123 .

[0065] Among them, the first end e1 of the detection unit 121 is electrically connected to the first end c of the dynamic electrostatic discharge module 12, the second end e2 of the detection unit 121 is electrically connected to the second end d of the dynamic electrostatic discharge module 12, and the detection unit 121 is configured to output a first voltage signal or a second voltage signal from the output end of the detection unit 121 according to the rate of change of the voltage of its first end e1.

[0066] The first end f1 of the trigger unit 122 is electrically connected to the first end c of the dynamic electrostatic discharge module 12, the second end f2 of the trigger unit 122 is electrically connected to the second end d of the dynamic electrostatic discharge module 12, and the control end f3 of the trigger unit 122 is electrically connected to the output end e3 of the detection unit 121; the trigger unit 122 is configured to output a conduction signal at the output end f4 of the trigger unit 122 according to the first voltage signal, and to output an off signal at the output end f4 of the trigger unit 122 according to the second voltage signal.

[0067] The first end g1 of the clamping unit 123 is electrically connected to the first end c of the dynamic electrostatic discharge module 12, the second end g2 of the clamping unit 123 is electrically connected to the second end d of the dynamic electrostatic discharge module 12, and the control end g3 of the clamping unit 123 is electrically connected to the output end f4 of the trigger unit 122; the clamping unit 123 is configured to conduct the first end g1 and the second end g2 according to the conduction signal, and to disconnect the first end g1 and the second end g2 according to the shutdown signal.

[0068] Specifically, in this embodiment, when the rate of change of the voltage at the first end e1 of the detection unit 121 is large, such as exceeding the preset rate of change threshold, that is, when dv2 / dt exceeds the preset rate of change threshold, the detection unit 121 outputs a first voltage signal; the trigger unit 122 can be turned on in response to the first voltage signal, thereby outputting a conduction signal; the clamping unit 123 is turned on in response to the conduction signal, thereby connecting the first end c of the dynamic electrostatic discharge module 12 with the second end d of the dynamic electrostatic discharge module 12, thereby connecting the power supply end Power with the ground end GND, and the static electricity of the power supply end Power is discharged. When the rate of change of the voltage at the first end e1 of the detection unit 121 does not exceed the preset rate of change threshold, the detection unit 121 outputs a second voltage signal, the trigger unit 122 is not turned on, so that the trigger unit 122 outputs a shutdown signal, and the clamping unit 123 is turned off in response to the shutdown signal.

[0069] Optionally, Fig.13 A schematic diagram of a circuit structure of a detection unit provided in an embodiment of the present invention, Fig.14 A circuit diagram of another detection unit provided in an embodiment of the present invention is shown in FIG. Fig.13 and Fig.14 The detection unit 121 includes a first resistor R1 and a detection capacitor C1, which are connected in series between a first terminal e1 of the detection unit and a second terminal e2 of the detection unit, and a common connection terminal of the first resistor R1 and the detection capacitor C1 is electrically connected to an output terminal e3 of the detection unit.

[0070] Specifically, in Fig.13In the illustrated embodiment, the first end of the detection capacitor C1 is electrically connected to the first end e1 of the detection unit 121, the second end of the detection capacitor C1 is electrically connected to the first end of the first resistor R1, the second end of the first resistor R1 is electrically connected to the second end e2 of the detection unit 121, and the second end of the detection capacitor C1 is electrically connected to the output end e3 of the detection unit 121. When the rate of change of the voltage at the first end c of the dynamic electrostatic discharge module 12 is large, that is, the rate of change of the voltage at the first end e1 of the detection unit 121 is large (corresponding to static electricity at the power supply end), the detection capacitor C1 is quickly charged, so that current flows through the detection unit 121, thereby causing the voltage across the first resistor R1 to change, so that the output end e3 of the detection unit 121 generates a first voltage signal. When the rate of change of the voltage at the first end e1 of the detection unit 121 is small (corresponding to voltage disturbance or normal power-on at the power supply end), the first capacitor C1 is equivalent to an open circuit state, and the voltage at the output end e3 of the detection unit 121 remains unchanged, that is, it remains as the second voltage signal.

[0071] exist Fig.14 In the illustrated embodiment, the first end of the first resistor R1 is electrically connected to the first end e1 of the detection unit 121, the second end of the first resistor R1 is electrically connected to the first end of the detection capacitor C1, the second end of the detection capacitor C1 is electrically connected to the second end e2 of the detection unit 121, and the first end of the detection capacitor C1 is electrically connected to the output end e3 of the detection unit 121. When the rate of change of the voltage at the first end c of the dynamic electrostatic discharge module 12 is large, that is, the rate of change of the voltage at the first end e1 of the detection unit 121 is large (corresponding to static electricity at the power supply end), the detection capacitor C1 is quickly charged, so that current flows through the detection unit 121, thereby causing the voltage at both ends of the first resistor R1 to change, so that the output end e3 of the detection unit 121 generates a first voltage signal. When the rate of change of the voltage at the first end of the detection unit 121 is small (corresponding to the power supply end being a voltage disturbance or normal power-on), the first capacitor C1 is equivalent to an open circuit state, and the voltage at the output end e3 of the detection unit 121 remains unchanged, that is, it remains as a second voltage signal.

[0072] In the above embodiment, the detection unit 121 adopts the method of connecting the first resistor R1 and the detection capacitor C1 in series, and the anti-disturbance module 11 is connected in series with the detection unit 121 of the dynamic electrostatic discharge module 12, so that the clamping unit 11A in the anti-disturbance module 11 and the detection capacitor C1 of the detection unit 121 can form a filtering and shaping circuit structure, and the signal of the power supply end Power is filtered and shaped, which can not only meet the function of electrostatic protection, but also have a low probability of false triggering. Furthermore, since the anti-disturbance module 11 is connected in series with the dynamic electrostatic discharge module 12, the anti-disturbance module 11 is not integrated in the dynamic electrostatic discharge module 12, so the detection unit 121, the trigger unit 122 and the clamping unit 123 in the dynamic electrostatic discharge module 12 will not be affected by the anti-disturbance module 11 when designing. The design method of various parameters in the anti-disturbance module 11 is relatively mature, so the electrostatic protection circuit of this embodiment has the advantages of easy implementation and low cost. In addition, the anti-disturbance module 11 is connected in series with the dynamic electrostatic discharge module 12, and the anti-disturbance module 11 has little effect on the speed of electrostatic triggering and the opening time of the clamping unit, so that the electrostatic protection circuit has a higher triggering speed and a longer conduction time, and static electricity can be effectively discharged. In addition, since the anti-disturbance module 11 and the dynamic electrostatic discharge module 12 are connected in series as a whole, the anti-disturbance module 11 will not affect the conduction degree of the clamping unit 123, that is, the voltage of the control terminal g3 of the clamping unit 123 can be pulled to the same potential as the first terminal g1, and the clamping unit 123 can be effectively turned on, thereby ensuring the electrostatic discharge speed.

[0073] Optionally, Fig.15 A schematic diagram of a circuit structure of a trigger unit provided in an embodiment of the present invention, Fig.16 A schematic diagram of a circuit structure of another trigger unit provided by an embodiment of the present invention. Fig.15 and Fig.16 The trigger unit 122 includes a first transistor M1 and a second resistor R2; the control end of the first transistor M1 is electrically connected to the control end f3 of the trigger unit 122. The first end of the first transistor M1 is electrically connected to the first end f1 of the trigger unit 122, the second end of the first transistor M1 is electrically connected to the first end of the second resistor R2, and the second end of the second resistor R2 is electrically connected to the second end f2 of the trigger unit 122.

[0074] Specifically, in Fig.15 In the embodiment shown, the first transistor M1 is an N-channel field effect transistor. If the corresponding first voltage signal is high and the second voltage signal is low, the on signal output by the trigger module is high and the off signal is low. If the first voltage signal is low and the second voltage signal is high, the on signal output by the trigger module is low and the off signal is high. Fig.16In the embodiment shown, the first transistor M1 is a P-channel field effect transistor. If the corresponding first voltage signal is high and the second voltage signal is low, the on signal output by the trigger module is low and the off signal is high. If the first voltage signal is low and the second voltage signal is high, the on signal output by the trigger module is high and the off signal is low.

[0075] Optionally, Fig.17 A circuit structure diagram of another trigger unit provided in an embodiment of the present invention, referring to Fig.17 In this embodiment, the trigger unit 122 includes a first transistor M1 and a second transistor M2 which are sequentially connected between a first terminal f1 of the trigger unit 122 and a second terminal f2 of the trigger unit 122; the control terminal of the first transistor M1 and the control terminal of the second transistor M2 are both electrically connected to the control terminal of the trigger unit 122; that is, the first terminal of the first transistor M1 is electrically connected to the first terminal f1 of the trigger unit 122, the second terminal of the first transistor M1 is electrically connected to the first terminal of the second transistor M2, and the second terminal of the second transistor M2 is electrically connected to the second terminal f2 of the trigger unit 122. The first transistor M1 is a P-channel transistor, and the second transistor M2 is an N-channel transistor. The first transistor M1 and the second transistor M2 form an inverter. When the first voltage signal is at a high level and the second voltage signal is at a low level, the on signal is at a low level and the off signal is at a high level; when the first voltage signal is at a low level and the second voltage signal is at a high level, the on signal is at a high level and the off signal is at a low level.

[0076] Optionally, Fig.18 A schematic diagram of a circuit structure of a clamping unit provided in an embodiment of the present invention. Fig.18 , the clamping unit 123 includes a third transistor M3, a first end of the third transistor M3 is electrically connected to the first end g1 of the clamping unit 123, a second end of the third transistor M3 is electrically connected to the second end g2 of the clamping unit 123, and a control end of the third transistor M3 is electrically connected to the control end of the clamping unit 123. The third transistor M3 can be a high-voltage n-channel field effect transistor, a high-voltage p-channel field effect transistor, a high-voltage pnp-type transistor, or a high-voltage npn-type transistor. When the clamping unit 123 is turned on, a low-resistance path can be provided for the power supply terminal and the ground terminal, so that static electricity can be discharged quickly. It can be understood that the channel type of the third transistor M3 needs to match the type of the turn-on signal and the turn-off signal.

[0077] For example, Fig.19 As shown, Fig.19 A schematic diagram of the circuit structure of another electrostatic protection circuit provided in an embodiment of the present invention. In this embodiment, the detection unit 121 can be used Fig.14The trigger unit 122 may adopt the structure shown in Fig.17 In this case, the clamping unit 123 may use an N-channel transistor. Alternatively, for example, Fig. 20 As shown, Fig. 20 A schematic diagram of the circuit structure of another electrostatic protection circuit provided in an embodiment of the present invention. In this embodiment, the detection unit 121 can be used Fig.13 The trigger unit 122 may adopt the structure shown in Fig.17 In the structure shown in , at this time, the clamping unit 123 can use a P-channel transistor.

[0078] The present invention further provides a chip, the chip comprising the electrostatic protection circuit provided by any embodiment of the present invention. Since the chip provided by the embodiment of the present invention comprises the electrostatic protection circuit provided by the embodiment of the present invention, it also has the same beneficial effects, which will not be described in detail here.

[0079] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An electrostatic protection circuit, characterized in that: The electrostatic protection circuit comprises: Anti-disturbance module, dynamic electrostatic discharge module, power supply terminal and grounding terminal; The anti-disturbance module and the dynamic electrostatic discharge module are connected in series between the power supply end and the ground end; wherein, the dynamic electrostatic discharge module is configured to control the conduction state of the power supply end and the ground end according to the change rate of the voltage transmitted from the power supply end to the dynamic electrostatic discharge module; the anti-disturbance module is configured to reduce the change rate of the voltage transmitted from the power supply end to the dynamic electrostatic discharge module.

2. The electrostatic protection circuit according to claim 1, characterized in that: The first end of the anti-disturbance module is electrically connected to the power supply end, the second end of the anti-disturbance module is electrically connected to the first end of the dynamic electrostatic discharge module, and the second end of the dynamic electrostatic discharge module is electrically connected to the ground end; Alternatively, the first end of the dynamic electrostatic discharge module is electrically connected to the power supply end, the second end of the dynamic electrostatic discharge module is electrically connected to the first end of the anti-disturbance module, and the second end of the anti-disturbance module is electrically connected to the ground end.

3. The electrostatic protection circuit according to claim 2, characterized in that: The anti-disturbance module comprises n voltage clamping units connected in series between a first end of the anti-disturbance module and a second end of the anti-disturbance module, and the voltage clamping units are configured to have a fixed voltage drop when turned on; n≥1, where n is an integer.

4. The electrostatic protection circuit according to claim 3, characterized in that: n≥2; the circuit structures of at least two of the clamping units are different; Alternatively, the circuit structures of all the clamping units are the same.

5. The electrostatic protection circuit according to claim 3 or 4, characterized in that: The voltage clamping unit includes at least one of a diode, a Zener tube, a GGNMOS, a PNP transistor, an NPN transistor and a silicon controlled rectifier.

6. The electrostatic protection circuit according to claim 2, characterized in that: The dynamic electrostatic discharge module comprises: A detection unit, wherein a first end of the detection unit is electrically connected to a first end of the dynamic electrostatic discharge module, a second end of the detection unit is electrically connected to a second end of the dynamic electrostatic discharge module, and the detection unit is configured to output a first voltage signal or a second voltage signal from an output end of the detection unit according to a rate of change of a voltage at the first end thereof; a trigger unit, wherein a first end of the trigger unit is electrically connected to a first end of the dynamic electrostatic discharge module, a second end of the trigger unit is electrically connected to the ground end, and a control end of the trigger unit is electrically connected to an output end of the detection unit; the trigger unit is configured to output an on signal at the output end of the trigger unit according to the first voltage signal, and output an off signal at the output end of the trigger unit according to the second voltage signal; A clamping unit, wherein the first end of the clamping unit is electrically connected to the first end of the dynamic electrostatic discharge module, the second end of the clamping unit is electrically connected to the second end of the dynamic electrostatic discharge module, and the control end of the clamping unit is electrically connected to the output end of the trigger unit; the clamping unit is configured to conduct the first end with its second end according to the conduction signal, and to disconnect the first end with its second end according to the shutdown signal.

7. The electrostatic protection circuit according to claim 6, characterized in that: The detection unit includes a first resistor and a detection capacitor, the first resistor and the detection capacitor are connected in series between a first end of the detection unit and a second end of the detection unit; a common connection end of the first resistor and the detection capacitor is electrically connected to an output end of the detection unit.

8. The electrostatic protection circuit according to claim 6, characterized in that: The trigger unit includes a first transistor and a second resistor; the control end of the first transistor is electrically connected to the control end of the trigger unit; the first end of the first transistor is electrically connected to the first end of the trigger unit, the second end of the first transistor is electrically connected to the first end of the second resistor, and the second end of the second resistor is electrically connected to the second end of the trigger unit; Alternatively, the trigger unit includes a first transistor and a second transistor connected in sequence between the first end of the trigger unit and the second end of the trigger unit; the control end of the first transistor and the control end of the second transistor are both electrically connected to the control end of the trigger unit; the first transistor is a P-channel transistor, and the second transistor is an N-channel transistor.

9. The electrostatic protection circuit according to claim 6, characterized in that: The clamping unit includes a third transistor, a first end of the third transistor is electrically connected to the first end of the clamping unit, a second end of the third transistor is electrically connected to the second end of the clamping unit, and a control end of the third transistor is electrically connected to the control end of the clamping unit.

10. A chip, characterized in that: The chip includes the electrostatic protection circuit according to any one of claims 1 to 9.

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