WO2019119980A1 - Electrostatic protection circuit, integrated circuit chip, and household appliance - Google Patents

Abstract

An electrostatic protection circuit, an integrated circuit chip, and a household appliance. The electrostatic protection circuit comprises a circuit unit to be protected (100), an input electrostatic protection unit (200), and an output electrostatic protection unit (300). The input electrostatic protection unit (200) is connected between an input terminal (VIN) of the circuit unit to be protected (100) and a preceding circuit stage. The output electrostatic protection unit (300) is connected between an output terminal (VOUT) of the circuit unit to be protected (100) and a following circuit stage. The invention adds the input electrostatic protection unit (200) at the input terminal (VIN) of the circuit unit to be protected (100) and adds the output electrostatic protection unit (300) at the output terminal (VOUT) of the circuit unit to be protected (100), so as to effectively resist the impact of a surge from the preceding or following circuit stage on the circuit unit to be protected.

Description

Electrostatic protection circuit, integrated circuit chip and household appliances

Technical field

The present application relates to the field of integrated circuit technology, and in particular, to an electrostatic protection circuit, an integrated circuit chip, and a household appliance.

Background technique

The high-voltage integrated circuit is a gate drive circuit with undervoltage protection and logic control. It combines power electronics with semiconductor technology and gradually replaces traditional discrete components. It is increasingly used in IGBTs and high power. The field of MOSFET driving. At HVIC (High ESD protection is an important part of the design when Voltage Integrated Circuit (HV Integrated Circuit) is designed.

The current mainstream HVIC ESD protection structure is shown in Figure 1:

The structure includes a diode (1) and a diode (2) at the input end, an integrated circuit domain (3), a diode (4) at the output end, and a diode (5).

The protection mechanism is simple input and output diode protection, and the circuit structure has limited impact resistance.

Application content

The main purpose of the present application is to propose an electrostatic protection circuit designed to improve the impact resistance of an integrated circuit.

To achieve the above objective, the electrostatic protection circuit proposed by the present application comprises a circuit unit to be protected, an input electrostatic protection unit and an output electrostatic protection unit, and the input electrostatic protection unit is connected to the input end of the circuit unit to be protected and the upper level circuit. The output electrostatic protection unit is connected between the output end of the circuit unit to be protected and the next-stage circuit.

In one embodiment, the input electrostatic protection unit includes a first diode and a first resistor, and an anode of the first diode is connected to an input end of the circuit unit to be protected and an end of the first resistor. The cathode of the first diode is connected to a power supply, and the other end of the first resistor is connected to the upper stage circuit.

In an embodiment, the input electrostatic protection unit further includes a second diode, and a cathode of the second diode is connected to a common end between the first resistor and the upper-level circuit, and the second The anode of the pole tube is grounded.

In an embodiment, the output electrostatic protection unit includes a third diode, and an anode of the third diode is connected to an output end of the circuit unit to be protected and a next-stage circuit, and the third The cathode of the pole tube is connected to a power supply.

In an embodiment, the output electrostatic protection unit further includes a fourth diode, a cathode of the fourth diode is connected to an anode of the third diode, and an anode of the fourth diode Ground.

In an embodiment, the output ESD protection unit further includes a first inverter and a second inverter connected in series, and an input end of the first inverter is connected to an output end of the circuit unit to be protected An output end of the first inverter is connected to an input end of the second inverter, an output end of the second inverter is opposite to an anode and a fourth diode of the third diode Cathode connection.

The present application also provides an integrated circuit chip, the chip includes an electrostatic protection circuit including a circuit unit to be protected, an input electrostatic protection unit, and an output electrostatic protection unit, the input electrostatic protection unit being connected to the circuit unit to be protected The output electrostatic protection unit is connected between the input end and the upper stage circuit between the output end of the circuit unit to be protected and the next stage circuit.

In one embodiment, the input electrostatic protection unit includes a first diode and a first resistor, and an anode of the first diode is connected to an input end of the circuit unit to be protected and an end of the first resistor. The cathode of the first diode is connected to a power supply, and the other end of the first resistor is connected to the upper stage circuit.

In an embodiment, the input electrostatic protection unit further includes a second diode, and a cathode of the second diode is connected to a common end between the first resistor and the upper-level circuit, and the second The anode of the pole tube is grounded.

In an embodiment, the output electrostatic protection unit includes a third diode, and an anode of the third diode is connected to an output end of the circuit unit to be protected and a next-stage circuit, and the third The cathode of the pole tube is connected to a power supply.

In an embodiment, the output electrostatic protection unit further includes a fourth diode, a cathode of the fourth diode is connected to an anode of the third diode, and an anode of the fourth diode Ground.

In an embodiment, the output ESD protection unit further includes a first inverter and a second inverter connected in series, and an input end of the first inverter is connected to an output end of the circuit unit to be protected An output end of the first inverter is connected to an input end of the second inverter, an output end of the second inverter is opposite to an anode and a fourth diode of the third diode Cathode connection.

In addition, the present application further provides a home appliance, which includes the integrated circuit chip as described above, and the integrated circuit chip refers to the above implementation, and details are not described herein again.

In an embodiment, the household appliance is an air conditioner or a refrigerator.

The electrostatic protection circuit of the technical solution of the present application and an integrated circuit chip including the same, the integrated circuit chip is usually HVIC (High Voltage Integrated Circuit, high voltage integrated circuit), the circuit unit to be protected in HVIC usually includes a gate drive circuit with undervoltage protection, logic control, etc., when the circuit unit to be protected is subjected to high voltage, high current, strong electromagnetic interference, frequent insertion When the high-low temperature working environment is pulled out, it is easy to generate electrostatic discharge. At this time, by adding an input electrostatic protection unit at the input end of the circuit unit to be protected and adding an output electrostatic protection unit at the output end of the circuit unit to be protected, the upper level can be effectively resisted. Or the surge impact of the lower-level circuit on the protection circuit.

DRAWINGS

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings to be used in the embodiments or the prior art description will be briefly described below. Obviously, the drawings in the following description are only It is a certain embodiment of the present application, and other drawings can be obtained according to the structures shown in the drawings without any creative work for those skilled in the art.

1 is a schematic diagram of a circuit structure of an exemplary static electricity protection circuit of the present application;

FIG. 2 is a schematic structural diagram of a circuit of an embodiment of an electrostatic protection circuit of the present application.

Description of the reference numerals:

Label name Label name 100 Protection circuit unit D4 Fourth diode 200 Input electrostatic protection unit R1 First resistance 300 Output electrostatic protection unit Q1 First inverter D1 First diode Q2 Second inverter D2 Second diode VCC Power supply D3 Third diode

The implementation, functional features and advantages of the present application will be further described with reference to the accompanying drawings.

Detailed ways

The technical solutions in the embodiments of the present application are clearly and completely described in the following with reference to the drawings in the embodiments of the present application. It is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present application without departing from the inventive scope are the scope of the present application.

It should be noted that all directional indications (such as up, down, left, right, front, back, ...) in the embodiments of the present application are only used to explain between components in a certain posture (as shown in the drawing). The relative positional relationship, the motion situation, and the like, if the specific posture changes, the directional indication also changes accordingly.

In addition, the descriptions of "first", "second", and the like in this application are used for the purpose of description only, and are not to be construed as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Thus, features defining "first" or "second" may include at least one of the features, either explicitly or implicitly. In addition, the technical solutions between the various embodiments may be combined with each other, but must be based on the realization of those skilled in the art, and when the combination of the technical solutions is contradictory or impossible to implement, it should be considered that the combination of the technical solutions does not exist. Nor is it within the scope of protection required by this application.

The application proposes an electrostatic protection circuit.

Referring to FIG. 2, FIG. 2 is a schematic structural diagram of an embodiment of an electrostatic protection circuit of the present application.

In the embodiment of the present application, as shown in FIG. 2, the static electricity protection circuit includes a circuit unit 100 to be protected, an input electrostatic protection unit 200, and an output static electricity protection unit 300. The input static electricity protection unit 200 is connected to the circuit unit 100 to be protected. Between the input terminal VIN and the upper stage circuit, the output electrostatic protection unit 300 is connected between the output terminal VOUT of the circuit unit 100 to be protected and the next stage circuit.

This ESD protection circuit is usually used in integrated circuit chips, especially HVIC (High Voltage Integrated). In the circuit, the high-voltage integrated circuit, the main circuit module in the HVIC, that is, the circuit unit 100 to be protected, generally includes a gate driving circuit having a function of undervoltage protection, logic control, etc., when the circuit unit 100 to be protected is subjected to high voltage and high current. In the case of strong electromagnetic interference, frequent insertion and removal, and high and low temperature working environment, electrostatic discharge is easily generated. At this time, the input electrostatic protection unit 200 and the output of the circuit unit 100 to be protected are increased by the input terminal VIN of the circuit unit 100 to be protected. The terminal VOUT increases the output electrostatic protection unit 300, and can effectively resist the surge impact of the upper or lower circuit to be protected by the protection circuit.

In an embodiment, the input electrostatic protection unit 200 includes a first diode D1 and a first resistor R1, and an anode of the first diode D1 and an input terminal VIN of the circuit unit 100 to be protected One end of a resistor R1 is connected, the cathode of the first diode D1 is connected to the power supply VCC, and the other end of the first resistor R1 is connected to the upper stage circuit.

When the upper-stage circuit is subjected to a forward surge impact on the input terminal VIN of the protection circuit unit 100, the current flowing to the power supply VCC is reduced by the cooperation of the first diode D1 and the first resistor R1, thereby reducing The possibility that the protection circuit unit 100 is subjected to a Latch-up phenomenon is to reduce the possibility that the circuit unit 100 to be protected is damaged by the forward surge of the upper circuit.

The input electrostatic protection unit 200 further includes a second diode D2, and a cathode of the second diode D2 is connected to a common terminal between the first resistor R1 and the upper stage circuit, and the second diode The anode of D2 is grounded.

When the upper-level circuit is subjected to a negative surge impact on the input terminal VIN of the protection circuit unit 100, the current flowing to the power supply VCC is also reduced by the cooperation of the second diode D2 and the first resistor R1. It is also possible to reduce the possibility of a latch-up phenomenon of the circuit unit 100 to be protected, that is, to reduce the possibility that the circuit unit 100 to be protected is damaged by the negative surge of the upper circuit.

Of course, the reverse surge impact of the to-be-protected circuit unit 100 on the upper circuit can also be prevented by inputting the electrostatic protection unit 200.

In an embodiment, the output electrostatic protection unit 300 includes a third diode D3, and the anode of the third diode D3 is connected to the output terminal VOUT of the circuit unit 100 to be protected, and the next stage circuit. The cathode of the third diode D3 is connected to the power supply VCC.

When the circuit to be protected 100 is damaged by a forward surge, the instantaneous large current is consumed by the third diode D3 by the action of the third diode D3, so that the current flowing to the lower stage circuit is reduced. The damage is retained in the circuit of this level, effectively reducing the possibility that the lower circuit is damaged by the forward surge.

In an embodiment, the output electrostatic protection unit 300 further includes a fourth diode D4, and a cathode of the fourth diode D4 is connected to an anode of the third diode D3, the fourth two The anode of the pole D4 is grounded.

When the circuit to be protected 100 is damaged by a negative surge, the instantaneous large current is consumed by the fourth diode D4 by the action of the fourth diode D4, so that the current flowing to the lower circuit is reduced. The damage is retained in the circuit of this level, effectively reducing the possibility that the lower circuit is damaged by the negative surge impact.

In an embodiment, the output static electricity protection unit 300 further includes a first inverter Q1 and a second inverter Q2 connected in series, the input end of the first inverter Q1 and the circuit unit to be protected An output terminal VOUT of 100 is connected, an output end of the first inverter Q1 is connected to an input end of the second inverter Q2, and an output end of the second inverter Q2 is connected to the third diode The anode of the tube D3 and the cathode of the fourth diode D4 are connected.

By means of two inverters connected in series, the effective signal outputted to the next stage circuit by the circuit unit 100 to be protected remains unchanged, and when the next stage circuit has a reverse surge impact on the output terminal VOUT of the protection circuit unit 100, By the cooperation of the first inverter Q1 and the second inverter Q2, the surge impact of the next-stage circuit to the protection circuit unit 100 is isolated, and the possibility that the circuit unit 100 to be protected is damaged by the surge of the lower-level circuit is reduced. Sex.

The present application further provides an integrated circuit chip, which includes the above-mentioned electrostatic protection circuit. The structure, working principle and beneficial effects of the electrostatic protection circuit are all referred to the above embodiments, and are not described herein again.

In addition, the present application further provides a household appliance, which may be an air conditioner or a refrigerator. Specifically, the home appliance includes an integrated circuit chip as described above, and therefore, reference is made to the embodiment of the above-described static electricity protection circuit, and no longer Narration.

The above description is only a preferred embodiment of the present application, and is not intended to limit the scope of the patents of the present application, and the equivalent structural transformation, or direct/indirect use, of the present application and the contents of the drawings is used in the present invention. All other related technical fields are included in the patent protection scope of the present application.

Claims (19)

An electrostatic protection circuit, comprising: a circuit unit to be protected, an input electrostatic protection unit, and an output electrostatic protection unit, wherein the input electrostatic protection unit is connected between an input end of the circuit unit to be protected and a higher-level circuit, the output The ESD protection unit is connected between the output of the circuit unit to be protected and the next-stage circuit. The static electricity protection circuit according to claim 1, wherein the input electrostatic protection unit comprises a first diode and a first resistor, an anode of the first diode and an input end of the circuit unit to be protected, One end of the first resistor is connected, the cathode of the first diode is connected to the power supply, and the other end of the first resistor is connected to the upper circuit. The static electricity protection circuit according to claim 2, wherein said input electrostatic protection unit further comprises a second diode, a common terminal between said cathode of said second diode and said first resistor and said upper circuit Connected, the anode of the second diode is grounded. The static electricity protection circuit according to claim 1, wherein the output electrostatic protection unit comprises a third diode, an anode of the third diode and an output end of the circuit unit to be protected, and a lower-level circuit Connected, the cathode of the third diode is connected to a power supply. The static electricity protection circuit according to claim 4, wherein said output electrostatic protection unit further comprises a fourth diode, a cathode of said fourth diode being connected to an anode of said third diode, said The anode of the fourth diode is grounded. The ESD protection circuit of claim 5, wherein the output ESD protection unit further comprises a first inverter and a second inverter connected in series, the input of the first inverter and the standby An output terminal of the protection circuit unit is connected, an output end of the first inverter is connected to an input end of the second inverter, and an output end of the second inverter is connected to the third diode The anode and the cathode of the fourth diode are connected. An integrated circuit chip, wherein the integrated circuit chip includes an electrostatic protection circuit including a circuit unit to be protected, an input electrostatic protection unit, and an output electrostatic protection unit, wherein the input electrostatic protection unit is connected to the circuit to be protected Between the input end of the unit and the upper level circuit, the output electrostatic protection unit is connected between the output end of the circuit unit to be protected and the next stage circuit. The static electricity protection circuit according to claim 7, wherein the input electrostatic protection unit comprises a first diode and a first resistor, an anode of the first diode and an input end of the circuit unit to be protected, One end of the first resistor is connected, the cathode of the first diode is connected to the power supply, and the other end of the first resistor is connected to the upper circuit. The static electricity protection circuit according to claim 8, wherein said input electrostatic protection unit further comprises a second diode, a common terminal between said cathode of said second diode and said first resistor and said upper circuit Connected, the anode of the second diode is grounded. The static electricity protection circuit according to claim 7, wherein said output electrostatic protection unit comprises a third diode, an anode of said third diode and an output of said circuit unit to be protected, and a lower stage circuit Connected, the cathode of the third diode is connected to a power supply. The static electricity protection circuit according to claim 10, wherein said output electrostatic protection unit further comprises a fourth diode, a cathode of said fourth diode being connected to an anode of said third diode, said The anode of the fourth diode is grounded. The ESD protection circuit according to claim 11, wherein said output ESD protection unit further comprises a first inverter and a second inverter connected in series, the input end of said first inverter and said An output terminal of the protection circuit unit is connected, an output end of the first inverter is connected to an input end of the second inverter, and an output end of the second inverter is connected to the third diode The anode and the cathode of the fourth diode are connected. A household appliance, wherein the household appliance includes an integrated circuit chip, the integrated circuit chip includes an electrostatic protection circuit including a circuit unit to be protected, an input electrostatic protection unit, and an output electrostatic protection unit, the input The ESD protection unit is connected between the input end of the circuit unit to be protected and the upper stage circuit, and the output ESD protection unit is connected between the output end of the circuit unit to be protected and the next stage circuit. The ESD protection circuit of claim 13 wherein said input ESD protection unit comprises a first diode and a first resistor, an anode of said first diode and an input of said circuit unit to be protected, One end of the first resistor is connected, the cathode of the first diode is connected to the power supply, and the other end of the first resistor is connected to the upper circuit. The static electricity protection circuit according to claim 14, wherein said input electrostatic protection unit further comprises a second diode, a common terminal between said cathode of said second diode and said first resistor and said upper circuit Connected, the anode of the second diode is grounded. The static electricity protection circuit according to claim 13, wherein the output electrostatic protection unit comprises a third diode, an anode of the third diode and an output end of the circuit unit to be protected, and a lower-level circuit Connected, the cathode of the third diode is connected to a power supply. The static electricity protection circuit according to claim 16, wherein said output electrostatic protection unit further comprises a fourth diode, a cathode of said fourth diode being connected to an anode of said third diode, said The anode of the fourth diode is grounded. The ESD protection circuit of claim 17, wherein said output ESD protection unit further comprises a first inverter and a second inverter connected in series, the input of said first inverter and said An output terminal of the protection circuit unit is connected, an output end of the first inverter is connected to an input end of the second inverter, and an output end of the second inverter is connected to the third diode The anode and the cathode of the fourth diode are connected. The home appliance of claim 13, wherein the home appliance is an air conditioner or a refrigerator.