Intelligent controllable electrostatic and surge protection circuit

Abstract

The application provides a kind of intelligent controllable electrostatic and surge protection circuit, including DC voltage resistance and trigger voltage control module, energy storage module, maintaining voltage control module and main discharge module, wherein the output end of the DC voltage resistance and trigger voltage control module is connected with the input end of the energy storage module and the control end of maintaining voltage control module respectively, the output end of the energy storage module is connected with the control end of the maintaining voltage control module, the control signal output end of the maintaining voltage control module is connected with the control end of main discharge module, the DC voltage resistance and trigger voltage control module is used for regulating trigger voltage, the energy storage module is used for adjusting the duration of maintaining voltage control module, and then controlling the discharge duration of main discharge module, the maintaining voltage control module is used for regulating maintaining voltage, the application can realize intelligent controllable trigger voltage, maintaining voltage, discharge duration and discharge voltage through the cooperation of each module.

Description

Technical Field

[0001] This invention relates to an electrostatic discharge (ESD) and surge protection circuit, specifically to an intelligent and controllable ESD and surge protection circuit. Background Technology

[0002] During the use of electronic devices, static electricity can easily be generated on the human body, clothing, and device surfaces due to friction, contact separation, and other reasons. When static electricity accumulates to a certain level, it will cause electrostatic discharge, releasing high-energy charges. This electrostatic discharge can seriously damage sensitive components such as integrated circuits inside electronic devices, leading to decreased device performance or even complete failure.

[0003] In some electronic devices that require high-voltage power supply, high-voltage electrostatic discharge (ESD) or surge protection circuits are needed to protect these electronic devices from electrostatic discharge or surge. Such protection circuits should meet two conditions: first, they should not be turned on when the electronic device is working normally; second, when an electrostatic discharge or surge pulse occurs, they should be able to immediately turn on to discharge the current and then turn off, so as not to affect the normal use of the electronic device.

[0004] Power clamping circuits commonly used for electrostatic discharge protection of high-voltage power supplies include TVS diodes or stacked Zener diodes triggered by junction breakdown. The advantage of these structures is that their IV curves usually have "no hysteresis" or "shallow hysteresis" characteristics, so that the voltage across the device after conduction will be higher than the power supply voltage, thus eliminating the risk of latch-up. However, the disadvantage is that the clamping voltage is large under high current, which can easily exceed the safe operating window of the protected circuit, leading to breakdown failure of the protected circuit. The second type of high-voltage ESD protection structure is a transient RC-MOS circuit triggered by the rising edge of an electrostatic pulse. The advantage of this type of circuit is that when the protected chip encounters an electrostatic event while powered off, its relatively small trigger and clamping voltage provides a large safety voltage window margin. The disadvantage is that when the protected chip is powered on and encounters a system-level electrostatic event such as a surge or an electron gun pulse as specified in IEC 61000-4-2 (a fundamental standard issued by the International Electrotechnical Commission suitable for electromagnetic compatibility testing of various electrical and electronic equipment), the clamping voltage of the high-voltage ESD protection circuit needs to be superimposed with the power supply voltage. This will cause the clamping voltage to increase dramatically, easily exceeding the safe operating window of the protected circuit. The third type of high-voltage ESD protection structure is an ESD protection circuit with hysteresis characteristics, such as an SCR (Silicon Controlled Resistor). Hysteresis can effectively help reduce the clamping voltage. However, because the sustaining voltage of an SCR is often very low and difficult to accurately assess and adjust, once the sustaining voltage falls below the operating voltage, it can easily cause latch-up of the equipment, leading to permanent thermal damage.

[0005] Therefore, the ESD protection circuit of high-voltage power supply always faces the dual challenges of continuously reducing clamping voltage and preventing latch-up risks. Summary of the Invention

[0006] To address the problems in the existing technology, this invention provides an intelligent and controllable electrostatic discharge and surge protection circuit, which can effectively resolve the contradiction between "reducing clamping voltage" and "suppressing latch-up" faced by traditional high-voltage ESD protection, and provides a good circuit solution for high-voltage ESD and EOS protection.

[0007] This invention discloses an intelligent controllable electrostatic discharge (ESD) and surge protection circuit, positioned between a first port and a second port. It includes a DC withstand voltage and trigger voltage control module, an energy storage module, a sustaining voltage control module, and a main discharge module. The input terminal of the DC withstand voltage and trigger voltage control module is connected to both the first and second ports, and its output terminal is connected to both the input terminal of the energy storage module and the control terminal of the sustaining voltage control module. The output terminal of the energy storage module is connected to the control terminal of the sustaining voltage control module, and the control signal output terminal of the sustaining voltage control module is connected to the control terminal of the main discharge module. The main discharge module is positioned between the first and second ports. The DC withstand voltage and trigger voltage control module regulates the trigger voltage. The energy storage module adjusts the continuous operating time of the sustaining voltage control module, thereby controlling the discharge time of the main discharge module. The sustaining voltage control module regulates the sustaining voltage. The main discharge module is controlled by the preceding sustaining voltage control module. This intelligent controllable ESD and surge protection circuit achieves intelligent controllability of the trigger voltage, sustaining voltage, discharge time, and discharge voltage through the DC withstand voltage and trigger voltage control module, energy storage module, sustaining voltage control module, and main discharge module.

[0008] Furthermore, the intelligent controllable electrostatic discharge and surge protection circuit operates in three states: a triggering phase, a sustaining phase, and a latch-off phase.

[0009] Triggering phase: When the voltage difference between the first port and the second port is greater than the trigger voltage, the triggering phase begins. The DC withstand voltage and trigger voltage control module activates the sustaining voltage control module, which in turn opens the main discharge module to discharge charge and simultaneously stores energy for the energy storage module.

[0010] Maintenance Phase: The DC withstand voltage and trigger voltage control module and / or energy storage module control the maintenance voltage control module to work continuously, thereby keeping the main discharge module in a charge discharge state. When the total voltage drop across the circuit continues to decrease and voltage hysteresis occurs, the DC withstand voltage and trigger voltage control module stops working.

[0011] Unlatch release phase: When the voltage of the energy storage module is lower than the operating voltage of the sustaining voltage control module, the sustaining voltage control module stops working, the main discharge module stops discharging charge, and the total voltage drop across the circuit rebounds and rises above the power supply voltage, exhibiting voltage hysteresis characteristics.

[0012] Furthermore, the DC withstand voltage and trigger voltage control module includes a first withstand voltage element with withstand voltage function and a current-limiting resistor connected in series therewith. The first withstand voltage element includes a forward diode string, or one or more of Zener diodes, Schottky diodes, bipolar transistors, GGNMOS or GDPMOS, either individually or in series.

[0013] Furthermore, the voltage sustaining control module includes a second voltage-resistant element with voltage withstand capability, a switching element, and a voltage divider unit, all connected in series. The second voltage-resistant element includes a forward diode string, or one or more of Zener diodes, Schottky diodes, bipolar transistors, GGNMOS, or GDPMOS, either individually or in series. The control signal output terminal of the DC withstand voltage and trigger voltage control module and the output terminal of the energy storage module are connected to the control terminal of the switching element.

[0014] Furthermore, the switching element includes a MOS switch or a BJT, and the voltage divider unit is a resistor or a resistor network.

[0015] Furthermore, the first port is connected to n IO ports P1-Pn respectively. The first withstand voltage element of the DC withstand voltage and trigger voltage control module has n connection control terminals A1-An. Each IO port is connected to the n connection control terminals A1-An one by one through a diode. The second withstand voltage element of the sustaining voltage control module has n control terminals B1-Bn connected to the DC withstand voltage and trigger voltage control module. Each IO port is also connected to the n control terminals B1-Bn one by one through a diode.

[0016] Furthermore, the first port includes a low-voltage port, a medium-voltage port, and a high-voltage port. The n IO ports P1-Pn are divided into three groups, and the three groups of IO ports are respectively connected to the low-voltage port, the medium-voltage port, and the high-voltage port. The main discharge module includes an LV main discharge element, an MV main discharge element, and an HV main discharge element. The LV main discharge element is disposed between the low-voltage port and the second port, the MV main discharge element is disposed between the medium-voltage port and the second port, and the HV main discharge element is disposed between the high-voltage port and the second port. The control terminals of the LV main discharge element, the MV main discharge element, and the HV main discharge element are connected to the control signal output terminal of the sustaining voltage control module.

[0017] Furthermore, the main discharge module includes MOSFETs and their stacked structures and / or BJTs and their stacked structures.

[0018] Furthermore, the main discharge module includes one or more main discharge elements, and the control terminal of each main discharge element is connected to the control signal output terminal of the sustaining voltage control module.

[0019] or,

[0020] The main discharge module includes m low-voltage discharge elements connected in series. The discharge module also includes a gate drive voltage distribution module. The gate drive voltage distribution module has m distribution voltage output terminals, which are respectively connected to the control terminals of the low-voltage discharge elements. The input terminal of the gate drive voltage distribution module is connected to the control signal output terminal of the sustaining voltage control module. m is a positive integer.

[0021] Furthermore, the intelligent controllable electrostatic discharge (ESD) and surge protection circuit is packaged as a separate ESD or surge protection chip. The ESD or surge protection chip includes a substrate, a drive control chip, a discharge chip, a first port pin, and a second port pin disposed on the substrate. The DC withstand voltage and trigger voltage control module, the energy storage module, and the sustaining voltage control module are integrated on the drive control chip, and the main discharge module is integrated on the discharge chip. The drive control chip and the discharge chip each have a first pin connected to the first port pin, a second pin connected to the second port pin, and a third pin interconnected with each other. The drive control chip controls the discharge chip to discharge the ESD or surge voltage on the first port pin or the second port pin through the third pin.

[0022] or,

[0023] The intelligent controllable electrostatic discharge and surge protection circuit is integrated on the chip that needs protection. The chip has an I / O ring, and the intelligent controllable electrostatic discharge and surge protection circuit is set in the I / O ring. The main discharge module has one or more main discharge elements, which are arranged along the I / O ring.

[0024] Compared with the prior art, the beneficial effects of the present invention are: the present invention has the advantages of adjustable trigger voltage, adjustable maintenance voltage, latch-up immunity, and low clamping voltage, which can effectively solve the contradiction between reducing clamping voltage and suppressing latch-up faced by traditional high voltage ESD protection, and provide a good circuit solution for high voltage ESD and EOS (Electrical Overstress) protection. Attached Figure Description

[0025] To more clearly illustrate the solutions in this invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0026] Figure 1(a) is the circuit schematic of Example 1 of the existing high-voltage port hysteresis-free Power Clamp circuit;

[0027] Figure 1(b) is the circuit schematic of Example 2 of the existing high-voltage port hysteresis-free Power Clamp circuit;

[0028] Figure 2 This is a schematic diagram of the IV characteristics of an RC transient-triggered Power Clamp circuit under both power-down and power-on conditions.

[0029] Figure 3 This is a circuit structure diagram of the first embodiment of the intelligent controllable electrostatic and surge protection circuit of the present invention;

[0030] Figure 4(a) is a transient voltage waveform diagram of the present invention under a single electrostatic or surge pulse;

[0031] Figure 4(b) is a diagram of the working mode of the first embodiment of the present invention in the triggering stage;

[0032] Figure 4(c) is a diagram of the working mode of the first embodiment of the present invention during the maintenance phase;

[0033] Figure 4(d) is a diagram of the working mode of the first embodiment of the present invention in the latch release stage;

[0034] Figure 5 This is a schematic diagram of the TLP IV characteristic curves corresponding to different energy storage module parameters in the first embodiment of the present invention;

[0035] Figure 6 This is a structural block diagram of the second embodiment of the present invention;

[0036] Figure 7(a) is a structural block diagram of the third embodiment of the present invention;

[0037] Figure 7(b) is a schematic diagram of the layout of the third embodiment of the present invention;

[0038] Figure 8 This is a packaging structure diagram of the fourth embodiment of the present invention;

[0039] Figure 9 This is a circuit structure diagram of the fifth embodiment of the present invention;

[0040] Figure 10 This is a circuit structure diagram of the sixth embodiment of the present invention. Detailed Implementation

[0041] Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention; the terms "comprising" and "having," and any variations thereof, in the specification, claims, and foregoing drawings are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the specification, claims, or foregoing drawings are used to distinguish different objects, not to describe a particular order.

[0042] In this invention, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment to other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this invention can be combined with other embodiments.

[0043] To enable those skilled in the art to better understand the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0044] Figures 1(a) and 1(b) show two common high-voltage port hysteresis-free Power Clamp circuits. Figure 1(a) is a high-voltage GC-NMOS discharge circuit. The gate of the discharge transistor Mbig1 is connected in series with a large resistor R1, and the gate-drain parasitic capacitance (Cgd) of Mbig1 itself forms an RC transient coupling circuit with R1. When an ESD event occurs, the transient gate coupling current generates a voltage drop across R1, and the channel of Mbig1 conducts to discharge the ESD current. Figure 1(b) is a static voltage breakdown triggered ESD protection circuit. When the port voltage exceeds the forward voltage of a series of Zener diodes connected in series, current will flow through resistor R2 and form a voltage drop V. R2 V R2 Once the value reaches the threshold voltage of the discharge NMOS transistor Mbig2, the channel discharge current of the discharge NMOS transistor Mbig2 is turned on. Both of these circuits are hysteresis-free protection circuits. One drawback of hysteresis-free protection circuits is that when an electrostatic discharge event occurs while the protected chip is powered on, the protection circuit of type 1(a) or 1(b) will generate a high clamping voltage, which can easily exceed the system's safe operating voltage range and fail to achieve effective protection.

[0045] Figure 2This refers to the TLP (Transmission Line Pulse Generator) IV characteristic curves of the RC transient-triggered Power Clamp circuit shown in Figure 1(a) under both power-down and power-on conditions. Curve 1 represents the TLP IV curve under power-down conditions. It can be observed that when the voltage on the protected port reaches the threshold voltage of the discharge tube Mbig1, the discharge tube Mbig1 can be activated to discharge the electrostatic current. The threshold voltage of the discharge tube in the RC transient-triggered Power Clamp circuit is usually very small, typically less than 2V. Using this circuit for ESD protection under power-down conditions has significant advantages in low clamping voltage and low trigger voltage. However, when the protected device is powered on, such as... Figure 2 Curve 2 indicates that the trigger voltage of the circuit needs to be superimposed with the power-on voltage VDD. This will cause the overall IV characteristic of the ESD protection circuit to shift to the right, increasing the clamping voltage of the protection circuit. This will significantly worsen the electrostatic protection effect under power-on conditions and may lead to premature failure.

[0046] like Figure 3 As shown, in order to solve the above-mentioned technical problems, the present invention proposes an intelligent and controllable electrostatic and surge protection circuit, which is set between port 1 and port 2. The circuit includes a DC withstand voltage and trigger control module, an energy storage module, a sustaining voltage control module, and a main discharge module.

[0047] The input terminal of the DC withstand voltage and trigger voltage control module is connected to the first port and the second port, and the output terminal is connected to the input terminal of the energy storage module and the control terminal of the sustaining voltage control module, respectively. The output terminal of the energy storage module is connected to the control terminal of the sustaining voltage control module, and the control signal output terminal of the sustaining voltage control module is connected to the control terminal of the main discharge module. The main discharge module is located between the first port and the second port. The DC withstand voltage and trigger voltage control module is used to regulate the trigger voltage. The energy storage module is used to adjust the continuous working time of the sustaining voltage control module, thereby controlling the discharge time of the main discharge module. The sustaining voltage control module is used to regulate the sustaining voltage. The main discharge module is controlled by the preceding sustaining voltage control module. The intelligent controllable electrostatic discharge and surge protection circuit realizes intelligent controllability of trigger voltage, sustaining voltage, discharge time, and discharge voltage through the DC withstand voltage and trigger voltage control module, the energy storage module, the sustaining voltage control module, and the main discharge module.

[0048] Overall, this invention has advantages such as adjustable trigger voltage, adjustable maintenance voltage, latch-up immunity, and low clamping voltage. It can effectively solve the contradiction between "reducing clamping voltage" and "suppressing latch-up" faced by traditional high-voltage ESD protection, and provide a good circuit solution for high-voltage ESD and EOS (Electrical Overstress) protection.

[0049] like Figure 3 As shown in the first embodiment of the present invention, the DC withstand voltage and trigger voltage control module is used to regulate the trigger voltage of the circuit of the present invention. By adjusting the circuit composition of this module, the trigger voltage can be adjusted within any range to meet the requirements of various operating voltages and effectively avoid the risk of "false triggering". This module includes various first withstand voltage components with withstand voltage capability and their series current-limiting resistors. The first withstand voltage components can be forward diode strings, Zener diodes, Schottky diodes, bipolar junction transistors (BJTs), GGNMOS, GDPMOS, etc., as well as their series or combinations. The current-limiting resistors are used for current limiting, so that they only serve as triggering functions and not as main discharge functions.

[0050] This invention relates to an energy storage module capable of storing specific amounts of energy to maintain the continuous operation of a subsequent "sustaining voltage control module." However, it's important to note that the energy stored in the module is limited, meaning it can only sustain the operation of the "sustaining voltage control module" for a limited time period (e.g., the duration of a surge pulse). After this time limit, the energy storage module, due to insufficient energy, will be unable to maintain the continued operation of the "sustaining voltage control module." In this invention, the energy storage time can be flexibly controlled by adjusting the circuit structure and parameters of the "energy storage module" to adapt to various electrostatic discharge types with different pulse widths. The energy storage module typically uses energy storage elements such as inductors and capacitors, and by adjusting the RC time constant τ, it can provide protection against various electrostatic and surge discharge models.

[0051] The sustaining voltage control module of this invention is used to regulate the sustaining voltage of the circuit. By adjusting the circuit composition of this module, the sustaining voltage can be adjusted within any range to meet various withstand voltage and clamping voltage requirements. The activation of this module depends on the preceding DC withstand voltage and trigger voltage control module, while subsequent continuous operation depends on the power supply of the energy storage module. Generally, the operating voltage of the DC withstand voltage and trigger voltage control module is higher than that of the sustaining voltage control module. Therefore, when the invention is triggered to start, the IV curve will exhibit a controllable hysteresis characteristic (snapback) to optimize the voltage clamping characteristics. As time passes, when the energy of the energy storage module is exhausted, the sustaining voltage control module will be forced to shut down. At this time, the IV curve of this invention will exhibit an anti-hysteresis characteristic, which is reflected in an increase in the clamping voltage to achieve timely and effective shutdown and avoid potential latch-up events. The core circuit of this module is a switching element, which can use a MOS switch or a BJT as the switch. Specifically, it can be a series network of various second withstand voltage elements with withstand voltage function and the switching transistor. In this invention, the controlled terminal (i.e., the gate of the MOS switch or the base of the BJT) is controlled by a DC withstand voltage and trigger voltage control module. The sustaining voltage of this invention is approximately equal to the sum of the voltage drops of the second withstand voltage element and the switch. The second withstand voltage element includes a forward diode string, or one or more of Zener diodes, Schottky diodes, bipolar transistors, GGNMOS, or GDPMOS, either individually or in series. The control signal output terminal of the DC withstand voltage and trigger voltage control module and the output terminal of the energy storage module are connected to the control terminal of the switch element. Additionally, this module also includes a voltage divider module in series. The voltage divider module can be a resistor network, and it provides the drive voltage for the subsequent main discharge module.

[0052] The main discharge module of this invention is the core component responsible for discharging static electricity or surge charge, and it is controlled by the preceding stage holding voltage control module. It can typically be a stacked structure of various high-voltage MOSFETs (such as LDMOS (laterally diffused metal-oxide semiconductor)), medium- and low-voltage MOSFETs, high-voltage BJTs (bipolar junction transistors), medium- and low-voltage BJTs, etc.

[0053] Overall, the various modules of this invention can be integrated onto analog or digital chips as an on-chip ESD and / or EOS protection solution, or used as a standalone off-chip protection chip.

[0054] As shown in Figure 4(a), the working state of the intelligent controllable electrostatic and surge protection circuit includes a triggering stage, a sustaining stage, and a latch-off stage. Each stage will be described separately below.

[0055] 1. Triggering Phase: When the voltage difference between port 1 and port 2 increases to the trigger voltage of the circuit of this invention, the DC withstand voltage and trigger control module starts working first. On the one hand, it activates the sustaining voltage control module, thereby starting the main discharge module; on the other hand, the DC withstand voltage and trigger control module can also charge the energy storage module at the same time. The main energy transfer between the modules in this phase is shown by the red arrow in Figure 4(b).

[0056] 2. Sustaining Phase: In this phase, the sustaining voltage control module relies primarily on the energy storage module to continue operating, ensuring the main discharge module remains in a charge-discharging state. The total voltage drop across the circuit decreases accordingly, exhibiting voltage hysteresis (Snapback). At this time, the DC withstand voltage and trigger control module is in an off state. The sustaining phase is the main process for discharging electrostatic and surge charges in this invention, and the sustaining time t2 needs to be greater than the pulse width of the protected electrostatic and surge waveforms. Thanks to the voltage hysteresis characteristic, this invention can significantly optimize the clamping voltage and significantly improve the electrostatic and surge protection effect. Note that the sustaining voltage Vh can be set lower than the power supply voltage VDD1 at this time, and latch-up risk does not need to be considered. The main energy transfer between the modules in this phase is shown by the red arrow in Figure 4(c).

[0057] 3. Unlatching Stage: As the energy storage module gradually depletes, it becomes insufficient to maintain the operation of the voltage control module. This causes the total voltage drop across the circuit to rebound and rise above the power supply voltage, exhibiting a voltage hysteresis characteristic. This characteristic primarily ensures that after discharging static electricity and surge charges, the invention can promptly unlatch itself and safely reset to the shutdown state, awaiting the next static electricity event. The main energy transfer between modules during this stage is shown by the red arrows in Figure 4(d).

[0058] This invention can be used for protection against various typical electrostatic discharge and surge discharge models, including but not limited to HBM (Human Body Model), TLP (Transmission Line Pulse), surge, CDM (Charged Device Model), MM (Machine Model), and contact discharge and air discharge as specified in IEC61000-4-2.

[0059] like Figure 5The present invention, for a 20V operating voltage port, constructs a TLP pulse model and obtains TLP IV characteristic curves using Spectre circuit simulation under different energy storage module parameter conditions. Curves 101 and 102 are IV characteristic curves obtained by adjusting the energy storage element parameters in the energy storage module, respectively, which can achieve precise control of trigger speed and hysteresis depth. Curve 103, on the other hand, is the IV characteristic curve obtained by simulation using a traditional power clamping architecture (structure in Figure 1(b)), exhibiting no hysteresis characteristics, but the voltage clamping capability is significantly worse than that of curves 101 and 102.

[0060] like Figure 6 As shown, as a second embodiment of the present invention, compared with the first embodiment, this embodiment uses m-level low-voltage discharge units stacked together to form the main discharge module to meet the withstand voltage requirements under high-voltage scenarios. At the same time, a gate drive voltage distribution module is added to provide gate drive voltages Vg1~Vgm to the m-level low-voltage discharge elements respectively, ensuring that each level of low-voltage discharge unit can be effectively turned on to discharge electrostatic current, where m is a positive integer.

[0061] As shown in Figure 7(a), as the third embodiment of the present invention, the first embodiment is divided into two parts: control circuit 3 and main discharge module 4. The main discharge module 4 can be composed of multiple groups of main discharge elements connected in parallel. This embodiment only shows 4 groups, that is, the first main discharge element to the fourth main discharge element share the same control circuit 3 to control their switching. The control circuit 3 is integrated by a DC withstand voltage and trigger voltage control module, an energy storage module and a sustaining voltage control module.

[0062] This embodiment has the following two advantages:

[0063] 1. In on-chip electrostatic discharge or surge protection, if there is a higher protection requirement between port 1 and port 2, the main discharge unit can be flexibly distributed in the top layer layout to obtain a more flexible and compact layout.

[0064] 2. Using a single set of control circuits saves layout area and manufacturing costs.

[0065] As shown in Figure 7(b), this embodiment arranges the circuit of the present invention in a top-level layout. In this example, it is integrated on the chip that needs protection. An IO ring is provided on the chip. The control circuit 3 and four sets of main discharge elements are arranged in the IO ring. The main discharge elements are arranged along the IO ring and distributed around the IO ring, and are controlled by a control circuit.

[0066] like Figure 8As shown, as the fourth embodiment of the present invention, this embodiment demonstrates a combined packaging scenario of the control circuit and the main discharge module in the third embodiment, forming a packaged chip 8. In this case, the control circuit 3 in the third embodiment evolves into an independent drive control chip 9, still mainly composed of a DC withstand voltage and trigger voltage control module, an energy storage module, and a sustaining voltage control module; while the main discharge module 4 also evolves into an independent discharge tube discrete chip 6 or a discrete device. The drive control chip 9 and the discharge tube discrete chip 6 each have three pins, representing the power supply terminal, ground terminal, and gate terminal, respectively. In the combined packaging application, the drive control chip 9 and the discharge tube discrete chip 6 are first fixed to the substrate 10 with insulating adhesive. Then, the gate terminals of the two chips are shorted by bonding wire 11 or RDL wiring; the power supply terminals of the two chips are shorted by bonding wire 11 or RDL wiring and led out to the external first port pin VDD PIN 5; similarly, the ground terminals of the two chips are also shorted by bonding wire or RDL wiring and led out to the external second port pin GND PIN 7. It should be noted that the purpose of this embodiment is to achieve a more flexible protection circuit design. Therefore, the packaging process is not limited to the wire bonding or RDL routing process here, but should be applicable to various typical integrated circuit packaging technologies. In addition, the encapsulation in this embodiment is also applicable to the PCB board level.

[0067] like Figure 9 As shown, in the fifth embodiment of the present invention, port 1 is connected to n IO ports P1-Pn respectively. The first withstand voltage element of the DC withstand voltage and trigger voltage control module is provided with n connection control terminals A1-An. Each IO port is connected to the n connection control terminals A1-An one by one through a diode. The second withstand voltage element of the sustaining voltage control module is provided with n control terminals B1-Bn connected to the DC withstand voltage and trigger voltage control module. Each IO port is also connected to the n control terminals B1-Bn one by one through a diode.

[0068] This embodiment extends the first embodiment to multi-port application scenarios, significantly saving the area of ​​the ESD protection chip. Specifically, based on the first embodiment, this embodiment expands the DC withstand voltage and trigger voltage control module to multi-port control (connection terminals A1~An) to achieve multiple trigger voltage selection specifications; simultaneously, the sustaining control module is also expanded to multi-port control (control terminals B1~Bn) to achieve multiple sustaining voltage selection specifications. In the circuit topology connection, three directional diodes are set for each protected port (P1~Pn): D1~Dn, Da1~Dan, and Db1~Dbn. Note that these directional diodes need to have sufficient reverse withstand voltage capability. Subsequently, D1~Dn are all shorted to an ESD bus and finally connected to port 1 of the main discharge module; while Da1~Dan are each connected to connection terminals A1~An of the control circuit 3 to achieve the corresponding "trigger voltage selection"; and Db1~Dbn are each connected to control terminals B1~Bn of the control circuit 3 to achieve the corresponding "sustaining voltage selection". In summary, this embodiment has the following advantages:

[0069] 1. Multiple protected I / O ports (P1~Pn) can reuse the same main discharge module, significantly saving chip area;

[0070] 2. The trigger voltage and sustaining voltage of multiple protected IO ports (P1~Pn) can be flexibly adjusted;

[0071] 3. Multiple protected I / O ports (P1~Pn) can correspond to different power domains, such as the low voltage domain, the middle voltage domain, and the high voltage domain, providing extremely high design flexibility. It is important to note that the main discharge module should be equipped with high-voltage devices to ensure consistent compatibility with the voltage withstand requirements of various power domains.

[0072] like Figure 10 As shown, this sixth embodiment of the present invention is a further variation based on the fifth embodiment.

[0073] Port 1 includes a low-voltage port, a medium-voltage port, and a high-voltage port. The n I / O ports P1-Pn are divided into three groups, and the three groups of I / O ports are respectively connected to the low-voltage port, the medium-voltage port, and the high-voltage port. The main discharge module includes an LV main discharge element, an MV main discharge element, and an HV main discharge element. The LV main discharge element is located between the low-voltage port and port 2, the MV main discharge element is located between the medium-voltage port and port 2, and the HV main discharge element is located between the high-voltage port and port 2. The control terminals of the LV main discharge element, the MV main discharge element, and the HV main discharge element are connected to the control signal output terminal of the sustaining voltage control module.

[0074] For multi-power domain applications, in the fifth embodiment, high-voltage devices must be used in the main discharge module to ensure consistent voltage withstand requirements. However, this is unfavorable for low-voltage and medium-voltage domains, as redundant withstand voltage capabilities lead to a decrease in electrostatic discharge (ESD) and surge protection efficiency. In contrast, this embodiment constructs multiple ESD rails (such as LV ESD BUS, MV ESD BUS, and HV ESD BUS) to connect various main discharge components with different voltage specifications (such as "LV main discharge module," "MV main discharge module," and "HV main discharge module"). This ensures that the voltage of the main discharge module remains consistent with the operating voltage of the protected port, thereby maximizing ESD and surge protection efficiency in each voltage domain.

[0075] The specific embodiments described above are preferred embodiments of the present invention and are not intended to limit the specific scope of the present invention. The scope of the present invention includes, but is not limited to, these specific embodiments. All equivalent changes made in accordance with the present invention are within the protection scope of the present invention.

Claims

1. An intelligent controllable electrostatic and surge protection circuit, disposed between a first port and a second port, characterized in that: The intelligent controllable electrostatic and surge protection circuit comprises a direct current voltage resistance and trigger voltage control module, an energy storage module, a maintaining voltage control module and a main discharge module, wherein an input end of the direct current voltage resistance and trigger voltage control module is connected with a first port and a second port, and output ends thereof are connected with an input end of the energy storage module and a control end of the maintaining voltage control module respectively, an output end of the energy storage module is connected with the control end of the maintaining voltage control module, a control signal output end of the maintaining voltage control module is connected with a control end of the main discharge module, and the main discharge module is arranged between the first port and the second port. The direct current voltage resistance and trigger voltage control module is used for regulating a trigger voltage, the energy storage module is used for adjusting a continuous working time length of the maintaining voltage control module, thereby controlling a discharge time length of the main discharge module, the maintaining voltage control module is used for regulating a maintaining voltage, and the main discharge module is controlled by the maintaining voltage control module of the previous stage. The intelligent controllable electrostatic and surge protection circuit realizes intelligent control of a trigger voltage, a maintaining voltage, a discharge time length and a discharge voltage through the direct current voltage resistance and trigger voltage control module, the energy storage module, the maintaining voltage control module and the main discharge module. The working state of the intelligent controllable electrostatic and surge protection circuit comprises a trigger stage, a maintaining stage and a latch release stage. In the trigger stage, when a voltage difference between the first port and the second port is greater than a trigger voltage, the trigger stage is entered, the direct current voltage resistance and trigger voltage control module activates the maintaining voltage control module, thereby starting the main discharge module to discharge charges, and the energy storage module is energized. In the maintaining stage, the direct current voltage resistance and trigger voltage control module and / or the energy storage module control the maintaining voltage control module to continuously work, thereby continuously keeping the main discharge module in a charge discharge state.

2. The intelligent controllable electrostatic and surge protection circuit according to claim 1, wherein: In the latch release stage, when a voltage of the energy storage module is less than a working voltage of the maintaining voltage control module, the maintaining voltage control module stops working, the main discharge module stops discharging charges, and a total voltage drop between the circuit is rebounded to above a power supply voltage, thereby presenting a voltage rebound characteristic.

3. The intelligent controllable electrostatic and surge protection circuit according to claim 2, wherein: The direct current voltage resistance and trigger voltage control module comprises a first voltage resistance element with a voltage resistance function and a current limiting resistor connected in series, the first voltage resistance element comprises a forward diode string, or one or more single or series combinations of a Zener diode, a Schottky diode, a bipolar transistor, a GGNMOS or a GDPMOS.

4. The intelligent controllable electrostatic and surge protection circuit of claim 3, wherein: The maintaining voltage control module comprises a second voltage resistance element with a voltage resistance function, a switch element and a voltage dividing unit connected in series, the second voltage resistance element comprises a forward diode string, or one or more single or series combinations of a Zener diode, a Schottky diode, a bipolar transistor, a GGNMOS or a GDPMOS, and a control signal output end of the direct current voltage resistance and trigger voltage control module and an output end of the energy storage module are connected with a control end of the switch element. The switch element comprises a MOS switch tube or a BJT, and the voltage dividing unit is a resistor or a resistor network.

5. The intelligent controllable electrostatic and surge protection circuit of claim 3, wherein: The first port is connected with n IO ports P1-Pn respectively, the first voltage-resistant element of the direct-current voltage-resistant and trigger voltage control module is provided with n connection control ends A1-An, each IO port is connected with the n connection control ends A1-An one by one through a diode respectively, the second voltage-resistant element of the maintaining voltage control module is provided with n control ends B1-Bn connected with the direct-current voltage-resistant and trigger voltage control module, and each IO port is also connected with the n control ends B1-Bn one by one through a diode respectively.

6. The intelligent controllable electrostatic and surge protection circuit of claim 5, wherein: The first port includes a low-voltage port, a medium-voltage port and a high-voltage port, the n IO ports P1-Pn are divided into three groups, and the three groups of IO ports are connected with the low-voltage port, the medium-voltage port and the high-voltage port one by one respectively, the main discharge module includes a LV main discharge element, a MV main discharge element and a HV main discharge element, the LV main discharge element is arranged between the low-voltage port and the second port, the MV main discharge element is arranged between the medium-voltage port and the second port, and the HV main discharge element is arranged between the high-voltage port and the second port, and the control ends of the LV main discharge element, the MV main discharge element and the HV main discharge element are connected with the control signal output end of the maintaining voltage control module.

7. The intelligent controllable electrostatic and surge protection circuit of claim 1, wherein: The main discharge module includes a MOSFET and a stack structure thereof and / or a BJT and a stack structure thereof.

8. The intelligent controllable electrostatic and surge protection circuit of claim 5, wherein: The main discharge module includes one or more than one main discharge element, the control end of each main discharge element is connected with the control signal output end of the maintaining voltage control module, Or, The main discharge module includes m low-voltage discharge elements connected in series, the discharge module further includes a gate drive voltage distribution module, the gate drive voltage distribution module is provided with m distribution voltage output ends connected with the control ends of the low-voltage discharge elements one by one respectively, the input end of the gate drive voltage distribution module is connected with the control signal output end of the maintaining voltage control module, and m is a positive integer.

9. The intelligent controllable electrostatic and surge protection circuit according to any of claims 1-8, characterized in that: The intelligent controllable electrostatic and surge protection circuit is packaged as a separate electrostatic protection or surge protection chip, the electrostatic protection or surge protection chip includes a substrate, a drive control chip, a discharge chip, a first port pin and a second port pin arranged on the substrate, wherein the direct-current voltage-resistant and trigger voltage control module, the energy storage module and the maintaining voltage control module are integrated on the drive control chip, the main discharge module is integrated on the discharge chip, the drive control chip and the discharge chip are respectively provided with a first pin connected with the first port pin, a second pin connected with the second port pin and a third pin connected with each other, and the drive control chip controls the discharge chip to discharge the electrostatic or surge voltage on the first port pin or the second port pin through the third pin, Or, The intelligent controllable electrostatic and surge protection circuit is integrated on a chip that needs protection, the chip is provided with an IO ring, the intelligent controllable electrostatic and surge protection circuit is arranged in the IO ring, the main discharge module is provided with one or more than one main discharge element, and the main discharge elements are arranged along the IO ring respectively.

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