Driving circuit, driving chip and electronic device

Abstract

This application discloses a driving circuit, a driving chip, and an electronic device, belonging to the field of power electronics technology. The driving circuit includes: a pull-up circuit, the first terminal of which is electrically connected to a power supply voltage node; a pull-down circuit, the second terminal of which is electrically connected to a ground node, the equivalent on-resistance of which is determined based on the device dimensions, which are configured to meet electrostatic discharge requirements; and an impedance unit, the first terminal of which is electrically connected to the first terminal of the pull-down circuit, and the second terminal of which is electrically connected to the second terminal of the pull-up circuit. The difference between the sum of the impedance unit's resistance and the pull-down circuit's equivalent on-resistance and the target driving resistance is less than an error threshold. The total equivalent resistance of the impedance unit and the pull-down circuit is close to the target driving resistance, ensuring that the circuit's driving capability meets the application scenario requirements and, while improving electrostatic discharge capability, ensuring that the circuit's driving capability remains within a predetermined range.

Description

Technical Field

[0001] This application belongs to the field of power electronics technology, and in particular relates to a drive circuit, a drive chip, and an electronic device. Background Technology

[0002] In electronic devices, driver chips are widely used in various circuit systems. During assembly, testing and use, the exposed pins of the chip are prone to transient high voltage due to electrostatic discharge (ESD) from the human body. The driving devices in the driver chip are usually too small to meet the discharge capacity of human body static electricity, which leads to breakdown and damage of the driving devices.

[0003] Traditional solutions use larger driving devices to improve their ESD discharge capability, but the driving capability of larger driving devices is too large and cannot meet the needs of application scenarios. Summary of the Invention

[0004] This application aims to address at least one of the technical problems existing in the prior art. To this end, this application proposes a driving circuit, a driving chip, and an electronic device that, while improving electrostatic discharge capability, ensures that the driving capability of the circuit is within a predetermined range, thereby improving the stability and reliability of the driving circuit.

[0005] In a first aspect, this application provides a driving circuit, including:

[0006] Pull-up circuit, the first terminal of the pull-up circuit is electrically connected to the power supply voltage node;

[0007] The second terminal of the pull-down circuit is electrically connected to the ground node. The equivalent on-resistance of the pull-down circuit is determined based on the size of the components in the pull-down circuit. The size of the components in the pull-down circuit is configured to meet the electrostatic discharge requirements.

[0008] The impedance unit has its first end electrically connected to the first end of the pull-down circuit and its second end electrically connected to the second end of the pull-up circuit. The difference between the sum of the resistance of the impedance unit and the equivalent conduction resistance of the pull-down circuit and the target driving resistance is less than the error threshold.

[0009] According to the driving circuit of this application, the equivalent total resistance of the impedance unit and the pull-down circuit is close to the target driving resistance, which can ensure that the driving capability of the circuit meets the requirements of the application scenario. While improving the electrostatic discharge capability, it can ensure that the driving capability of the circuit is within the predetermined range, thereby improving the stability and reliability of the driving circuit.

[0010] According to one embodiment of this application, the impedance unit includes a polysilicon resistor, the first end of which is electrically connected to the first end of the pull-down circuit, and the second end of which is electrically connected to the second end of the pull-up circuit.

[0011] According to one embodiment of this application, the length L and width W of the polysilicon resistor satisfy the following relationship:

[0012]

[0013] Among them, R L Rc is the equivalent on-resistance of the pull-down circuit, Rc is the target drive resistance, and Rsp is the sheet resistance of the polysilicon resistor.

[0014] According to one embodiment of this application, the pull-up circuit includes a P-type MOS transistor, the source of which is electrically connected to the power supply voltage node, and the drain of which is electrically connected to the second terminal of the impedance unit.

[0015] According to one embodiment of this application, the pull-down circuit includes an N-type MOS transistor, the source of which is electrically connected to a ground node, and the drain of which is electrically connected to the first terminal of an impedance unit.

[0016] According to one embodiment of this application, the driving circuit includes:

[0017] Multiple inverters are used. The input terminals of the inverters are used to receive control signals, and the output terminals of the inverters are electrically connected to the driving terminals of either the pull-up or pull-down switching transistors.

[0018] According to one embodiment of this application, the driving circuit further includes:

[0019] The clamping circuit has its first terminal electrically connected to the power supply voltage node and its second terminal electrically connected to the grounding node. The clamping circuit is configured to form an electrostatic discharge path when the electrostatic voltage is greater than the voltage threshold.

[0020] According to one embodiment of this application, the clamping circuit includes:

[0021] An electromagnetic energy storage device, the first end of which is electrically connected to the power supply voltage node;

[0022] The resistor has its first end electrically connected to the second end of the electromagnetic energy storage device.

[0023] The clamping switch has its first terminal electrically connected to the power supply voltage node, its second terminal electrically connected to the second terminal of the resistor and the ground node, and its drive terminal electrically connected to the second terminal of the electromagnetic energy storage device.

[0024] Secondly, this application provides a driver chip that includes the aforementioned driver circuit.

[0025] According to the driver chip of this application, by reasonably configuring the channel size of the pull-down switch transistor to meet the requirements of human body electrostatic discharge, the breakdown and damage of the driving device caused by electrostatic discharge can be avoided. At the same time, the equivalent total resistance of the impedance unit and the pull-down switch transistor is close to the target driving resistance value, which can ensure that the driving capability of the circuit meets the requirements of the application scenario. While improving the electrostatic discharge capability, it can ensure that the driving capability of the circuit is within the predetermined range, thereby improving the stability and reliability of the driving circuit.

[0026] Thirdly, this application provides an electronic device that includes the aforementioned driver chip.

[0027] According to the electronic device of this application, the equivalent total resistance of the impedance unit and the pull-down switch is close to the target driving resistance, which can ensure that the driving capability of the circuit meets the requirements of the application scenario. While improving the electrostatic discharge capability, it can ensure that the driving capability of the circuit is within a predetermined range, thereby improving the stability and reliability of the driving circuit.

[0028] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0029] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0030] Figure 1 This is one of the circuit topologies of the driving circuit provided in the embodiments of this application;

[0031] Figure 2 This is the second circuit topology diagram of the driving circuit provided in the embodiments of this application;

[0032] Figure 3 This is the third circuit topology diagram of the driving circuit provided in the embodiments of this application.

[0033] Figure label:

[0034] Drive circuit 10, clamping circuit 20, first pull-up switch Q1, second pull-up switch Q3, third pull-up switch Q5, first pull-down switch Q2, second pull-down switch Q4, third pull-down switch Q6, first to third polysilicon resistors Ra1 to Ra3, inverter A, electromagnetic energy storage device C, resistor R0, clamping switch Q3, power supply voltage node VCC, ground node GND. Detailed Implementation

[0035] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0036] In the following description, a "circuit" refers to a conductive loop consisting of at least one element or sub-circuit connected by an electrical or electromagnetic link. When an element or circuit is said to be "coupled to" or "connected to" another element, or when an element / circuit is said to be "coupled at" or "connected at" two nodes, it can be directly coupled to or connected to the other element, or there may be intermediate elements. The connection between elements can be physical, logical, or a combination thereof. Conversely, when an element is said to be "directly coupled to" or "directly connected to" another element, it means that there are no intermediate elements between them.

[0037] In the description, the terms "first," "second," etc., are used to distinguish similar objects, not to describe a specific order or sequence. It should be understood that such numerical descriptors can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class, not limited in number; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0038] Furthermore, the use of terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicates that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0039] Figure 1 The circuit topology of the driving circuit 10 provided in an embodiment of this application is shown. (Refer to...) Figure 1One embodiment of this application proposes a driving circuit 10, including: a pull-up circuit, a pull-down circuit, and an impedance unit. The first terminal of the pull-up circuit is electrically connected to the power supply voltage node VCC; the second terminal of the pull-down circuit is electrically connected to the ground node GND. The equivalent on-resistance of the pull-down circuit is determined based on the device dimensions in the pull-down circuit, and the device dimensions in the pull-down circuit are configured to meet electrostatic discharge requirements. The first terminal of the impedance unit is electrically connected to the first terminal of the pull-down circuit, and the second terminal of the impedance unit is electrically connected to the second terminal of the pull-up circuit. The difference between the sum of the first resistance of the impedance unit and the equivalent on-resistance of the pull-down circuit and the target driving resistance is less than an error threshold.

[0040] The driving circuit 10 is mainly used to provide a driving signal to the switch transistor to be driven, so as to drive the switch transistor to switch between the on and off states. The driving circuit 10 includes a pull-up circuit, an impedance unit, and a pull-down circuit connected in series. The connection node of the pull-up circuit and the impedance unit can serve as the output node of the driving circuit 10, providing a driving signal.

[0041] The pull-up circuit may include a first pull-up switch Q1. The first terminal of the first pull-up switch Q1 is electrically connected to the power supply voltage node VCC. The first pull-up switch Q1 can switch between an on state and an off state. When the first pull-up switch Q1 is in the on state, it can pull the voltage signal of the output node high to a certain level, so that the drive circuit 10 outputs a high-level signal.

[0042] The pull-down circuit may include a first pull-down switch Q2. The second terminal of the first pull-down switch Q2 is electrically connected to the ground node GND, and the first terminal of the first pull-down switch Q2 is electrically connected to the output node through an impedance unit. The first pull-down switch Q2 can switch between an on state and an off state. When the first pull-down switch Q2 is in the on state, it can pull the voltage signal of the output node down to ground potential, causing the drive circuit 10 to output a low-level signal.

[0043] Taking an N-type MOSFET as an example, when the first pull-up switch Q1 is in the on state and the first pull-down switch Q2 is in the off state, the driving circuit 10 outputs a high-level signal to drive the N-type MOSFET to turn on; when the first pull-up switch Q1 is in the off state and the first pull-down switch Q2 is in the on state, the driving circuit 10 outputs a low-level signal to drive the N-type MOSFET to turn on.

[0044] The number of pull-up and pull-down switches in the driver circuit 10 can be selected according to the actual application scenario, and is not limited here. The number of pull-up and pull-down switches can be the same or different. For example, the driver circuit 10 may include one pull-up switch and one pull-down switch, or the driver circuit 10 may include three pull-up switches and three pull-down switches, or the driver circuit 10 may include two pull-up switches and three pull-down switches, etc.

[0045] Figure 2 The circuit topology of the driving circuit 10 provided in an embodiment of this application is shown. (Refer to...) Figure 2 For example, the drive circuit 10 includes three pull-up switches and three pull-down switches.

[0046] The first pull-up switch Q1, the second pull-up switch Q3, and the third pull-up switch Q5 have different sizes, so their pull-up strengths are different. The first pull-down switch Q2, the second pull-down switch Q4, and the third pull-down switch Q6 also have different sizes, so their pull-down strengths are different. The drive circuit 10 composed of three pull-up switches and three pull-down switches can form nine different combinations of drive strengths.

[0047] In practical applications, different pull-up and pull-down switches can be selected to conduct based on the required driving capability of the switch to be driven. The dimensions of the pull-up and pull-down switches can be adjusted according to the needs of the actual application. The following explanation uses a pull-up circuit including the first pull-up switch Q1 and a pull-down circuit including the first pull-down switch Q2 as an example.

[0048] It should be noted that the drive circuit 10 is usually integrated into the drive chip. The output node of the drive circuit 10 is electrically connected to the exposed pins of the chip. During assembly, testing and use, the exposed pins of the chip are prone to transient high voltage due to electrostatic discharge from the human body. During the electrostatic discharge process, the first pull-down switch Q2 may be accidentally turned on. Therefore, the channel size of the first pull-down switch Q2 needs to be appropriately increased to meet the requirements of electrostatic discharge. That is, by reasonably designing the size of the switch, it can effectively withstand the impact of electrostatic discharge from the human body and prevent electrostatic damage to the drive device.

[0049] It is understandable that the larger the channel size of the first pull-down switch Q2, the smaller its equivalent on-resistance and the stronger its driving capability. In scenarios where a weak driving capability is required, increasing the channel size of the first pull-down switch Q2 to improve its electrostatic discharge resistance may result in its driving capability not meeting the requirements.

[0050] An impedance unit is connected in series at the first terminal of the first pull-down switch Q2, such that the difference between the sum of the first resistance of the impedance unit and the equivalent on-resistance of the first pull-down switch Q2 and the target driving resistance is less than the error threshold. In other words, the sum of the first resistance and the equivalent on-resistance of the first pull-down switch Q2 is approximately equal to the target driving resistance. The overall resistance of the impedance unit and the first pull-down switch Q2 is approximately equal to the target driving resistance relative to the output node of the drive circuit 10. That is, the portion of the reduction in the equivalent on-resistance of the first pull-down switch Q2 caused by increasing the channel size to meet electrostatic discharge is compensated by the resistance of the impedance unit, so that the overall driving capability of the impedance unit and the first pull-down switch Q2 remains unchanged.

[0051] Understandably, in order to ensure that the driving capability of the first pull-down switch Q2 meets the requirements, when the driving circuit 10 includes multiple first pull-down switches Q2, each first pull-down switch Q2 should be connected in series with an impedance unit whose equivalent on-resistance is matched, so that the impedance unit and the first pull-down switch Q2 as a whole maintain a constant driving capability. That is, the difference between the sum of the equivalent on-resistance of each first pull-down switch Q2 and the resistance of the impedance unit connected in series with it and the target driving resistance is less than the error threshold.

[0052] The specific value of the error threshold can be determined based on the actual application scenario, and is not limited here. For example, the specific value of the error threshold can be 0.05Ω or 0.01Ω, etc.

[0053] By increasing the channel size of the first pull-down switch Q2, static electricity can be effectively dispersed and discharged, thereby preventing damage to the first pull-down switch Q2 and improving circuit stability. By reasonably configuring the resistance value of the impedance unit, the driving capability of the drive circuit 10 can be guaranteed, ensuring the normal operation of the system under high load. In summary, the design of the drive circuit 10 in this application can find a balance between static discharge and driving capability. The design of the drive circuit 10 proposed in this application can not only meet the requirements of static discharge, but also ensure that the driving capability of the circuit meets the requirements of the application scenario, effectively avoid circuit failures caused by electrostatic discharge, and improve the overall reliability of the circuit.

[0054] According to the driving circuit 10 of this application, by reasonably configuring the channel size of the first pull-down switch Q2 to meet the requirements of human body electrostatic discharge, the breakdown and damage of the driving device caused by electrostatic discharge can be avoided. At the same time, the equivalent total resistance of the impedance unit and the first pull-down switch Q2 is close to the target driving resistance value, which can ensure that the driving capability of the circuit meets the requirements of the application scenario. While improving the electrostatic discharge capability, it can ensure that the driving capability of the circuit is within the predetermined range, thereby improving the stability and reliability of the driving circuit 10.

[0055] In some embodiments, the impedance unit includes a first polysilicon resistor Ra1, the first end of which is electrically connected to the first end of the pull-down circuit, and the second end of which is electrically connected to the second end of the pull-up circuit.

[0056] Polycrystalline silicon resistors are resistive elements manufactured using a self-aligned process. They are typically made of metal silicide materials. Due to the good conductivity of silicides, polycrystalline silicon resistors have relatively low sheet resistance.

[0057] The first polysilicon resistor Ra1 is connected in series with the first pull-down switch Q2. The difference between the sum of the resistance of the first polysilicon resistor Ra1 and the equivalent on-resistance of the first pull-down switch Q2 and the target driving resistance is less than the error threshold, so that the driving capability of the driving circuit 10 can meet the needs of the application scenario.

[0058] It should be noted that when the drive circuit 10 includes multiple pull-down switching transistors, each pull-down switching transistor should be connected in series with a polysilicon resistor. Each pull-down switching transistor has a different size, and the resistance value of the polysilicon resistor connected in series is also different, so that the difference between the sum of the resistance value of the polysilicon resistor and the equivalent on-resistance value of the pull-down switching transistor connected in series and the target drive resistance value is less than the error threshold.

[0059] Continue to refer to Figure 2 As an example, the impedance unit includes a first polysilicon resistor Ra1, a second polysilicon resistor Ra2, and a third polysilicon resistor Ra3. The first polysilicon resistor Ra1 is connected in series with the first pull-down switch Q2, the second polysilicon resistor Ra2 is connected in series with the second pull-down switch Q4, and the third polysilicon resistor Ra3 is connected in series with the third pull-down switch Q6.

[0060] In some embodiments, the equivalent on-resistance R of the first pull-down switch Q2 is... L Calculate using the following formula:

[0061]

[0062] Where Rsp1 is the on-resistance of the first pull-down switch Q2, W1 is the channel width of the first pull-down switch Q2, and L1 is the length of the first pull-down switch Q2.

[0063] The electrostatic voltage that the first pull-down switch Q2 needs to withstand is usually 2KV. The size of the first pull-down switch Q2 (including the channel width W1 and the length L1 of the first pull-down switch Q2) can be determined based on the electrostatic voltage of the human body. In addition, once the device type of the first pull-down switch Q2 is determined, the value of its specific on-resistance Rsp1 is also determined.

[0064] Given Rsp1 = R L*A①,R L Let R be the equivalent on-resistance of the first pull-down switch Q2, and A be the device area of ​​the first pull-down switch Q2. Then, A = W1 * L1 ②. Combining formulas ① and ②, the equivalent on-resistance R of the first pull-down switch Q2 can be determined. L The calculation formula.

[0065] As an example, the specific on-resistance Rsp1 of the first pull-down switch Q2 is 5mΩ·mm. 2 The first pull-down switch Q2, which needs to withstand the electrostatic voltage from the human body, has a channel width W1 = 400µm and a length L1 = 0.6µm. Substituting the equivalent on-resistance R mentioned above... L From the calculation formula, R can be calculated. L ≈20.83Ω.

[0066] In some embodiments, the length L and width W of the polysilicon resistor Ra satisfy the following relationship:

[0067]

[0068] Where Rc is the target driving resistance and Rsp is the sheet resistance of the polysilicon resistor Ra.

[0069] To ensure that the driving capability of the driving circuit 10 meets the requirements of the application scenario, the sum of the resistance value of the polysilicon resistor Ra and the equivalent on-resistance value of the first pull-down switch Q2 should be approximately equal to the target driving resistance value. The equivalent on-resistance value R of the first pull-down switch Q2 is determined according to the aforementioned embodiment. L Then, it can be based on R A =Rc-R L Calculate the resistance value Ra of the polysilicon resistor, where R A This is the resistance value Ra of the polycrystalline silicon resistor.

[0070] The overall width of the polysilicon resistor Ra needs to meet the electrostatic discharge requirements. The width W2 of the polysilicon resistor Ra can be determined based on the electrostatic voltage of the human body. Furthermore, once the device type of the polysilicon resistor Ra is determined, its sheet resistance Rsp is also determined. The resistance value R of the polysilicon resistor Ra... A =Rsp*L2 / W2, combined with R A =Rc-R L This allows us to determine the formula for calculating the length L2 of the polycrystalline silicon resistor Ra, and thus determine the dimensions of the polycrystalline silicon resistor Ra.

[0071] After determining the dimensions of the first pull-down switch Q2 that needs to meet the electrostatic discharge requirements, the resistance value of the first pull-down switch Q2 is calculated based on its dimensions and specific on-resistance. Combined with the target driving resistance value, the resistance value of the polysilicon resistor Ra is calculated. Based on the resistance value of the polysilicon resistor Ra, its sheet resistance, and its width, the length L2 of the polysilicon resistor Ra can be calculated, thus determining its dimensions. This ensures that the first pull-down switch Q2 meets the electrostatic discharge requirements, preventing it from being damaged by breakdown, and also ensures that the driving capability of the driving circuit 10 meets the application scenario requirements, improving stability and reliability.

[0072] In some embodiments, the first pull-up switch Q1 is a P-type MOSFET and the first pull-down switch Q2 is an N-type MOSFET.

[0073] The source of the P-type MOSFET is electrically connected to the supply voltage node VCC, and the drain is electrically connected to the second terminal of the polysilicon resistor Ra. This connection node serves as the output node of the drive circuit 10. The gate of the P-type MOSFET controls the current flow. When the gate voltage is lower than the source voltage, the P-type MOSFET turns on, allowing current to flow from the supply voltage node VCC to the output terminal, providing a high-level signal. Since the turn-on condition of the P-type MOSFET is that the gate voltage is lower than the source voltage, appropriate voltage control is typically used to drive the high-level signal.

[0074] The source of the N-type MOSFET is electrically connected to the ground node GND, and the drain is electrically connected to the first terminal of the polysilicon resistor Ra. The gate of the N-type MOSFET controls the flow of current. When the gate voltage is higher than the source voltage, the N-type MOSFET is turned on, allowing current to flow from the output node of the drive circuit 10 to the ground node GND, providing a low-level signal. The conduction condition of the N-type MOSFET is that the gate voltage is higher than the source voltage; therefore, a low-level drive can be achieved by controlling the gate voltage.

[0075] P-type and N-type MOSFETs are complementary, enabling more efficient switching operations. The P-type MOSFET is primarily used to pull the voltage of the output node of the driver circuit 10 high, while the N-type MOSFET is primarily used to pull the voltage of the output node of the driver circuit 10 low. This complementarity allows the circuit to operate with lower power consumption, especially in the quiescent state, where almost no current flows through the switching transistor, thus reducing power consumption.

[0076] In some embodiments, the driving circuit 10 includes a plurality of inverters A, the input terminal of which is used to receive a control signal, and the output terminal of which is electrically connected to the driving terminal of the first pull-up switch Q1 or the driving terminal of the first pull-down switch Q2.

[0077] Inverter A is a common logic circuit component, typically possessing strong driving capability. The input terminal of inverter A is used to receive control signals, and its output terminal is electrically connected to either the driving terminal of the first pull-up switch Q1 or the driving terminal of the first pull-down switch Q2. The output terminal of inverter A can provide a large current to drive the driving terminal of either the pull-up or first pull-down switch Q2.

[0078] The control signal is used to control the switching of the first pull-up switch Q1 and the first pull-down switch Q2 between the on and off states. The driving terminal of each first pull-up switch Q1 and the driving terminal of each first pull-down switch Q2 are respectively electrically connected to an inverter A. The inverter A gradually amplifies the signal strength based on the control signal, thereby ensuring that the control signal can effectively drive the switch and overcome any possible circuit impedance.

[0079] In some embodiments, the drive circuit 10 further includes a clamping circuit 20, a first terminal of which is electrically connected to the power supply voltage node VCC, and a second terminal of which is electrically connected to the ground node GND. The clamping circuit 20 is configured to form an electrostatic discharge path when the electrostatic voltage is greater than a voltage threshold.

[0080] The clamping circuit 20 is primarily used to provide a low-impedance discharge path when the voltage reaches a certain threshold, diverting excess electrostatic energy to ground or power supply and preventing electrostatic accumulation from affecting circuit components. During an electrostatic discharge event, when the voltage rises rapidly and exceeds the designed voltage threshold range, the clamping circuit 20 allows the electrostatic discharge to flow out through a specially designed discharge path, thereby ensuring circuit safety.

[0081] It should be noted that the specific value of the voltage threshold can be determined based on the actual application scenario, and is not limited here. For example, the voltage threshold can be 500V or 600V, etc.

[0082] The clamping circuit 20 can not only effectively protect the drive circuit 10 from electrostatic discharge damage, but also automatically disconnect the discharge path and restore the normal working state of the circuit after the electrostatic voltage returns to a safe value.

[0083] The clamping circuit 20 improves the circuit's anti-interference capability and anti-static performance, thereby increasing the reliability and stability of the drive circuit 10.

[0084] In some embodiments, the clamping circuit 20 includes an electromagnetic energy storage device C, a resistor R0, and a clamping switch Q3. A first terminal of the electromagnetic energy storage device C is electrically connected to the power supply voltage node VCC; a first terminal of the resistor R0 is electrically connected to a second terminal of the electromagnetic energy storage device C; a first terminal of the clamping switch Q3 is electrically connected to the power supply voltage node VCC; a second terminal of the clamping switch Q3 is electrically connected to both the second terminal of the resistor R0 and the ground node GND; and a driving terminal of the clamping switch Q3 is electrically connected to the second terminal of the electromagnetic energy storage device C.

[0085] When the output node of the drive circuit 10 receives static electricity, the discharge path of the static electricity is transmitted from the drain terminal of the pull-up clamp switch Q3 through the body diode of the pull-up clamp switch Q3 to the supply voltage node VCC. The voltage at the supply voltage node VCC charges the electromagnetic energy storage device C. When the voltage at the supply voltage node VCC is greater than the voltage threshold, the voltage at the second terminal of the electromagnetic energy storage device C is also greater than the voltage threshold, driving the clamp switch Q3 to conduct, forming a low-impedance discharge path, and conducting the static electricity at the supply voltage node VCC to the ground node GND.

[0086] The specific type of electromagnetic energy storage device C can be determined based on the actual application scenario and is not limited here. For example, electromagnetic energy storage device C can be a capacitor, with its first terminal electrically connected to the power supply voltage node VCC, and its second terminal electrically connected to the first terminal of resistor R0 and the drive terminal of clamping switch Q3.

[0087] Resistor R0 and capacitor are connected to form a delay circuit. The resistance value of resistor R0 and the capacitance value of capacitor can be determined according to the actual application scenario to enable clamping switch Q3 to conduct within a certain time after receiving static electricity, thus forming a static discharge path.

[0088] One embodiment of this application provides a driver chip that includes the aforementioned driver circuit 10.

[0089] The structure and working principle of the drive circuit 10 can be referred to the aforementioned embodiments, and will not be repeated here.

[0090] According to the driver chip of this application, by reasonably configuring the channel size of the first pull-down switch Q2 to meet the requirements of human body electrostatic discharge, the breakdown and damage of the driving device caused by electrostatic discharge can be avoided. At the same time, the equivalent total resistance of the polysilicon resistor Ra and the first pull-down switch Q2 is close to the target driving resistance value, which can ensure that the driving capability of the circuit meets the requirements of the application scenario. While improving the electrostatic discharge capability, it can ensure that the driving capability of the circuit is within the predetermined range, thereby improving the stability and reliability of the driver circuit 10.

[0091] Thirdly, this application provides an electronic device that includes the aforementioned driver chip.

[0092] According to the electronic device of this application, by reasonably configuring the channel size of the first pull-down switch Q2 to meet the requirements of human body electrostatic discharge, the breakdown damage of the driving device caused by electrostatic discharge can be avoided. At the same time, the equivalent total resistance of the polysilicon resistor Ra and the first pull-down switch Q2 is close to the target driving resistance value, which can ensure that the driving capability of the circuit meets the requirements of the application scenario. While improving the electrostatic discharge capability, it can ensure that the driving capability of the circuit is within the predetermined range, thereby improving the stability and reliability of the driving circuit 10.

[0093] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A drive circuit characterized by comprising: include: A pull-up circuit, wherein the first terminal of the pull-up circuit is electrically connected to the power supply voltage node; A pull-down circuit, wherein the second terminal of the pull-down circuit is electrically connected to a ground node, and the equivalent on-resistance of the pull-down circuit is determined based on the device dimensions in the pull-down circuit, wherein the device dimensions in the pull-down circuit are configured to meet the electrostatic discharge requirements; An impedance unit is provided, wherein the first end of the impedance unit is electrically connected to the first end of the pull-down circuit, and the second end of the impedance unit is electrically connected to the second end of the pull-up circuit. The difference between the sum of the resistance value of the impedance unit and the equivalent on-resistance value of the pull-down circuit and the target driving resistance value is less than an error threshold.

2. The drive circuit according to claim 1, characterized by The impedance unit includes a polysilicon resistor, the first end of which is electrically connected to the first end of the pull-down circuit, and the second end of which is electrically connected to the second end of the pull-up circuit.

3. The drive circuit according to claim 2, characterized in that, The length L and width W of the polycrystalline silicon resistor satisfy the following relationship: ； Wherein, RL is the equivalent on-resistance of the pull-down circuit, Rc is the target driving resistance, and Rsp is the sheet resistance of the polysilicon resistor.

4. The drive circuit according to claim 1, characterized by The pull-up circuit includes a P-type MOS transistor, the source of which is electrically connected to the power supply voltage node, and the drain of which is electrically connected to the second terminal of the impedance unit.

5. The drive circuit according to claim 1, characterized by The pull-down circuit includes an N-type MOS transistor, the source of which is electrically connected to the ground node, and the drain of which is electrically connected to the first terminal of the impedance unit.

6. The driving circuit according to any one of claims 1-5, characterized in that, The driving circuit includes: Multiple inverters are provided, the input terminals of which are used to receive control signals, and the output terminals of which are electrically connected to the driving terminals of either a pull-up switch or a pull-down switch.

7. The drive circuit according to any one of claims 1 to 5, characterized by, The driving circuit also includes: A clamping circuit, wherein a first terminal of the clamping circuit is electrically connected to the power supply voltage node, and a second terminal of the clamping circuit is electrically connected to the grounding node, and the clamping circuit is configured to form an electrostatic discharge path when the electrostatic voltage is greater than a voltage threshold.

8. The drive circuit according to claim 7, characterized in that, The clamping circuit includes: An electromagnetic energy storage device, wherein a first terminal of the electromagnetic energy storage device is electrically connected to the power supply voltage node; A resistor, wherein the first end of the resistor is electrically connected to the second end of the electromagnetic energy storage device; A clamping switch is provided, wherein the first end of the clamping switch is electrically connected to the power supply voltage node, the second end of the clamping switch is electrically connected to the second end of the resistor and the grounding node, and the driving end of the clamping switch is electrically connected to the second end of the electromagnetic energy storage device.

9. A driving chip, characterized by, Includes the drive circuit according to any one of claims 1-8.

10. An electronic device, comprising: Includes the driver chip according to claim 9.

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