CN218526303U

CN218526303U - High current-carrying electronic switch with breakdown protection function

Info

Publication number: CN218526303U
Application number: CN202222259339.6U
Authority: CN
Inventors: 张宇航
Original assignee: Nanjing Yanzhan Technology Co ltd
Current assignee: Nanjing Yanzhan Technology Co ltd
Priority date: 2022-08-26
Filing date: 2022-08-26
Publication date: 2023-02-24
Anticipated expiration: 2032-08-26

Abstract

The utility model discloses a high current-carrying electronic switch with puncture protect function, including electronic switch, electronic switch includes PMOS pipe array, three-terminal fuse array and drive circuit, PMOS pipe drive circuit, differential current sampling circuit and MCU controller, electronic switch has four pins, four pins are VIN pin, GND pin, VO pin, SGIN pin respectively; VIN pin is connected to battery BAT's positive pole, and GND pin is connected to battery BAT's negative pole, and the VO pin is connected to LOAD LOAD's one end, and LOAD LOAD's the other end is connected to battery BAT's negative pole equally, and the SGIN pin is connected to external control signal. The utility model discloses a high current-carrying electronic switch with puncture protect function has solved that traditional electronic switch current-carrying capacity is little, drive circuit is complicated, with high costs, do not possess the problem of functions such as overcurrent protection and puncture protection.

Description

High current-carrying electronic switch with breakdown protection function

Technical Field

The utility model belongs to the technical field of electronic switch's technique and specifically relates to a high current-carrying electronic switch with puncture protect function is related to.

Background

Switching elements such as mechanical switches and electromagnetic relays are widely used in various industrial production fields. However, due to the existence of the mechanical structure, the service life of the mechanical switch is short, and the switching speed is slow. In addition, the arc, electrical surge, and the like, which are easily generated during the mechanical operation, may damage not only the switch itself but also the load device. Moreover, the mechanical switch generally does not have the protection functions of overcurrent, overload and the like, and particularly when the mechanical switch fails, the load equipment can continuously work and then be damaged.

An electronic switch is a device which adopts a semiconductor device to realize a switching function, and gradually replaces a common mechanical switch in many occasions due to high switching speed, long service life, no electric arc and no discharge. But the current capacity of the semiconductor device is limited, the current-carrying capacity of the traditional electronic switch is small, and the application occasion of a high-current-carrying circuit is difficult to meet.

In addition, the NMOS transistor is often used as the semiconductor device in the conventional electronic switch, which results in a complex driving circuit and high cost. Meanwhile, the traditional electronic switch does not have the functions of overcurrent protection, breakdown protection and the like, and when a semiconductor device is broken down and fails, the load equipment is difficult to separate from a working circuit.

SUMMERY OF THE UTILITY MODEL

The to-be-solved technical problem of the utility model is not enough to above-mentioned prior art, and provide a high current-carrying electronic switch with puncture protect function, it has current-carrying quantity height, longe-lived, drive circuit advantage simple, with low costs to possess overcurrent protection, puncture protect function, it is more reliable to compare mechanical switch or traditional electronic switch during operation.

In order to achieve the above object, the present invention provides a high current-carrying electronic switch with breakdown protection function, which has the following specific technical scheme:

a high current-carrying electronic switch with a breakdown protection function comprises an electronic switch, wherein the electronic switch comprises a PMOS (P-channel metal oxide semiconductor) tube array, a three-terminal fuse array and driving circuit, a PMOS tube driving circuit, a differential current sampling circuit and an MCU (microprogrammed control unit) controller, and the electronic switch is provided with four pins which are a VIN (VIN) pin, a GND (ground) pin, a VO (voltage input) pin and an SGIN (ground reference input) pin respectively;

the VIN pin is connected to the anode of the battery BAT, the GND pin is connected to the cathode of the battery BAT, the VO pin is connected to one end of the LOAD, the other end of the LOAD is connected to the cathode of the battery BAT, and the SGIN pin is connected to an external control signal.

Further, the PMOS tube array comprises a PMOS tube S1, a PMOS tube S2 and a PMOS tube S3; the source electrodes of the PMOS tube S1, the PMOS tube S2 and the PMOS tube S3 are connected together in a short-circuit mode and are connected to the VIN pin; the drains of the PMOS tube S1, the PMOS tube S2 and the PMOS tube S3 are connected together in a short circuit and connected to the input end of the three-terminal fuse array and the drive circuit; the grid electrodes of the PMOS tube S1, the PMOS tube S2 and the PMOS tube S3 are connected together in a short circuit mode and are connected to the output end of the PMOS tube driving circuit.

Furthermore, the three-terminal FUSE array and the driving circuit comprise a three-terminal FUSE1, a three-terminal FUSE2, a three-terminal FUSE3, an NMOS tube Q1 and a driving resistor R1; the first FUSE ends of the three-terminal FUSE FUSE1, the three-terminal FUSE FUSE2 and the three-terminal FUSE FUSE3 are in short circuit together and are used as the input ends of the three-terminal FUSE array and the driving circuit; the second FUSE ends of the three-terminal FUSE FUSE1, the three-terminal FUSE FUSE2 and the three-terminal FUSE FUSE3 are in short circuit together, are used as the output ends of the three-terminal FUSE array and the driving circuit and are connected to the VO pin; heating ends of the three-terminal FUSE FUSE1, the three-terminal FUSE FUSE2 and the three-terminal FUSE FUSE3 are connected together in a short circuit mode and are connected to a drain electrode of the NMOS tube Q1; the grid electrode of the NMOS tube Q1 is connected to a 3 pin of the MCU controller through a driving resistor R1; the source of the NMOS tube Q1 is connected to the GND pin.

Further, the PMOS tube driving circuit comprises a voltage regulator tube Z1, an NMOS tube Q2, a current limiting resistor R3 and a driving resistor R4; the cathode of the voltage-stabilizing tube Z1 is connected with one end of a current-limiting resistor R2 and is connected to VIN; the anode of the voltage stabilizing tube Z1 is connected with the other end of the current limiting resistor R2, is connected with one end of the current limiting resistor R3, is used as the output end of the PMOS tube driving circuit, and is connected with the grid electrode of the PMOS tube array; the other end of the current-limiting resistor R3 is connected with the drain electrode of the NMOS tube Q2; the grid electrode of the NMOS tube Q2 is connected to a pin 2 of the MCU controller through a driving resistor R4; the source of the NMOS transistor Q2 is connected to the GND pin.

Further, the differential current sampling circuit comprises a voltage division resistor R5, a voltage division resistor R6, a voltage division resistor R7, a voltage division resistor R8, a proportional amplification resistor R9, a proportional amplification resistor R10, a proportional amplification resistor R11, a proportional amplification resistor R12 and an operational amplifier OP1; one end of the divider resistor R5 is connected to the VO pin, and the other end of the divider resistor R5 is connected to the GND pin through the divider resistor R6; one end of a divider resistor R7 is connected to the VO pin, and the other end of the divider resistor R8 is connected to the GND pin; one end of the proportional amplifying resistor R9 is connected to the common end of the voltage dividing resistor R5 and the voltage dividing resistor R6; the other end of the proportional amplifying resistor R9 is connected to the negative input end of the operational amplifier OP1 and is connected to the output end of the operational amplifier OP1 through the proportional amplifying resistor R10; one end of the proportional amplifying resistor R10 is connected to the common end of the voltage dividing resistor R7 and the voltage dividing resistor R8; the other end of the proportional amplifying resistor R10 is connected to the positive input end of the operational amplifier OP1 and is connected to the GND pin through the proportional amplifying resistor R12; the output end of the operational amplifier OP1 is connected to the 4-pin of the MCU controller.

Further, the resistance values of the voltage dividing resistor R5 and the voltage dividing resistor R7 are the same.

Further, the resistance values of the voltage dividing resistor R6 and the voltage dividing resistor R8 are the same.

Further, the proportional amplifying resistor R9 has the same resistance as the proportional amplifying resistor R11.

Further, the proportional amplifying resistor R10 and the proportional amplifying resistor R12 have the same resistance.

Compared with the prior art, the beneficial effects of the utility model are that:

the utility model discloses a high current-carrying electronic switch with breakdown protection function, adopt the form of PMOS pipe array can provide the higher current-carrying capacity than traditional electronic switch to and simple structure, drive circuit with low costs; the three-terminal fuse array can provide a breakdown protection function which is not possessed by a traditional electronic switch, and is quicker than the traditional fuse fusing and more accurate in judgment; the differential current sampling circuit provides an overcurrent protection function which is not provided by the traditional electronic switch, and judges whether an overcurrent condition occurs or not by detecting the conduction voltage drop, thereby realizing the protection function of the electronic switch.

Drawings

Fig. 1 is a circuit diagram of a high current-carrying electronic switch with breakdown protection function according to the present invention;

the notation in the figure is: 1. an electronic switch; 2. a PMOS tube array; 3. a three-terminal fuse array and a driving circuit; 4. a PMOS tube driving circuit; 5. a differential current sampling circuit.

Detailed Description

In order to better understand the purpose, structure and function of the present invention, the following description is made in detail with reference to the accompanying drawings and the preferred embodiments for a high current-carrying electronic switch with breakdown protection function.

Example 1:

referring to fig. 1, the present invention provides a technical solution: a high current-carrying electronic switch with a breakdown protection function comprises an electronic switch 1, wherein the electronic switch 1 comprises a PMOS tube array 2, a three-terminal fuse array and drive circuit 3, a PMOS tube drive circuit 4, a differential current sampling circuit 5 and an MCU (microprogrammed control unit) controller, and the electronic switch 1 is provided with four pins which are respectively a VIN pin, a GND pin, a VO pin and an SGIN pin;

the VIN pin is connected to the anode of the battery BAT, the GND pin is connected to the cathode of the battery BAT, the VO pin is connected to one end of the LOAD LOAD, the other end of the LOAD LOAD is connected to the cathode of the battery BAT, and the SGIN pin is connected to an external control signal; the electronic switch (1) is switched on and off under the control of an external control signal, and output and stop are realized at a VO pin, so that the function of controlling whether the LOAD LOAD is connected to a working circuit or not is realized.

Further, the PMOS tube array 2 comprises a PMOS tube S1, a PMOS tube S2 and a PMOS tube S3; the source electrodes of the PMOS tube S1, the PMOS tube S2 and the PMOS tube S3 are connected together in a short-circuit mode and are connected to the VIN pin; the drains of the PMOS tube S1, the PMOS tube S2 and the PMOS tube S3 are connected together in a short circuit and connected to the input end of the three-terminal fuse array and the drive circuit 3; the grid electrodes of the PMOS tube S1, the PMOS tube S2 and the PMOS tube S3 are connected together in a short-circuit mode and are connected to the output end of the PMOS tube driving circuit 4; when the grid voltage of the PMOS tube is pulled up to the VIN pin, the PMOS tube array 2 is switched off; when the voltage difference between the source electrode and the grid electrode of the PMOS tube is greater than the threshold voltage, the PMOS tube array 2 is switched on; the PMOS tube array 2 reduces the requirement on the complexity of a driving circuit while providing a high current-carrying electronic switching function.

Further, the three-terminal FUSE array and driving circuit 3 comprises a three-terminal FUSE1, a three-terminal FUSE2, a three-terminal FUSE3, an NMOS transistor Q1 and a driving resistor R1; the first FUSE ends of the three-terminal FUSE FUSE1, the three-terminal FUSE FUSE2 and the three-terminal FUSE FUSE3 are shorted together to be used as the input end of the three-terminal FUSE array and the driving circuit (3); the second FUSE ends of the three-terminal FUSE FUSE1, the three-terminal FUSE FUSE2 and the three-terminal FUSE FUSE3 are in short circuit together, are used as the output ends of the three-terminal FUSE array and the driving circuit 3 and are connected to the VO pin; heating ends of the three-terminal FUSE FUSE1, the three-terminal FUSE FUSE2 and the three-terminal FUSE FUSE3 are connected together in a short circuit mode and connected to a drain electrode of the NMOS tube Q1; the grid electrode of the NMOS tube Q1 is connected to a 3 pin of the MCU controller through a driving resistor R1; the source electrode of the NMOS tube Q1 is connected to the GND pin; when the MCU controller detects that the PMOS tube array 2 has a breakdown condition, outputting a high level at a 3 pin of the MCU controller to drive an NMOS tube Q1 to be conducted; the internal heaters of the three-terminal FUSE FUSE1, the three-terminal FUSE FUSE2 and the three-terminal FUSE FUSE3 start to work until the internal FUSEs are fused, and the LOAD LOAD is separated from a working loop, so that the breakdown protection is realized.

Further, the PMOS transistor driving circuit 4 includes a voltage regulator tube Z1, an NMOS transistor Q2, a current limiting resistor R3, and a driving resistor R4; the cathode of the voltage-stabilizing tube Z1 is connected with one end of a current-limiting resistor R2 and is connected to VIN; the anode of the voltage stabilizing tube Z1 is connected with the other end of the current limiting resistor R2, is connected with one end of the current limiting resistor R3, is used as the output end of the PMOS tube driving circuit 4, and is connected with the grid electrode of the PMOS tube array 2; the other end of the current-limiting resistor R3 is connected with the drain electrode of the NMOS tube Q2; the grid electrode of the NMOS tube Q2 is connected to a pin 2 of the MCU controller through a driving resistor R4; the source electrode of the NMOS tube Q2 is connected to the GND pin; when the MCU controller SGIN receives a starting signal, a high level is output at a pin 2 to drive an NMOS tube Q2 to be conducted; VIN generates a loop through the current-limiting resistors R2 and R3 and a drain-source electrode of an NMOS tube, generates a voltage difference larger than a threshold voltage between a source electrode and a grid electrode of the PMOS tube array (2) and is limited to a stabilized voltage of a voltage stabilizing tube Z1, and protects the PMOS tube array 2 from being broken down by grid overvoltage while the PMOS tube array 2 is conducted; when the MCU SGIN receives a closing signal, a low level is output at a pin 2 to turn off an NMOS tube Q2; the current limiting resistor R2 pulls up the grid voltage of the PMOS tube array 2 to VIN, and the PMOS tube array 2 is turned off; the PMOS tube driving circuit 4 does not need a boosting unit, and has simple structure and low cost.

Further, the differential current sampling circuit 5 comprises a voltage dividing resistor R5, a voltage dividing resistor R6, a voltage dividing resistor R7, a voltage dividing resistor R8, a proportional amplifying resistor R9, a proportional amplifying resistor R10, a proportional amplifying resistor R11, a proportional amplifying resistor R12 and an operational amplifier OP1; one end of the divider resistor R5 is connected to the VO pin, and the other end of the divider resistor R5 is connected to the GND pin through the divider resistor R6; one end of a divider resistor R7 is connected to the VO pin, and the other end of the divider resistor R8 is connected to the GND pin; one end of the proportional amplifying resistor R9 is connected to the common end of the voltage dividing resistor R5 and the voltage dividing resistor R6; the other end of the proportional amplifying resistor R9 is connected to the negative input end of the operational amplifier OP1 and is connected to the output end of the operational amplifier OP1 through the proportional amplifying resistor R10; one end of the proportional amplifying resistor R10 is connected to the common end of the voltage dividing resistor R7 and the voltage dividing resistor R8; the other end of the proportional amplifying resistor R10 is connected to the positive input end of the operational amplifier OP1 and is connected to the GND pin through the proportional amplifying resistor R12; the output end of the operational amplifier OP1 is connected to a 4-pin of the MCU controller; when the PMOS tube array 2 is conducted, the output voltage of the operational amplifier OP1 and the conducted voltage drop from VIN to VO are in a linear relation, when the 4-pin of the MCU controller detects that the voltage is too high, the electronic switch is indicated to have an overcurrent phenomenon, and the electronic switch is turned off by outputting a level at the 2-pin to realize overcurrent protection; when the PMOS tube array 2 is switched off, when the 4 pins of the MCU controller detect that the voltage is too low, the breakdown phenomenon of the electronic switch PMOS tube is shown, and the breakdown protection is realized by fusing the three-terminal fuse array at the 3 pins by outputting high level.

The working principle is as follows:

the utility model provides a high current-carrying electronic switch with puncture protect function, include: the device comprises a PMOS tube array 2, a three-terminal fuse array and drive circuit 3, a PMOS tube drive circuit 4, a differential current sampling circuit 5 and an MCU controller.

The PMOS transistor array 2 includes, but is not limited to: PMOS tubes S1, S2 and S3; the on-off function of the electronic switch is realized by controlling the on-off of the PMOS tube array; the current-carrying capacity of the electronic switch can be effectively improved by adopting 3 PMOS tubes to form a PMOS tube array; the PMOS tube array can solve the problem that a driving circuit is complex due to the adoption of NMOS tubes in the traditional electronic switch, so that the overall cost of the electronic switch is reduced.

The three-terminal fuse array and driving circuit 3 includes, but is not limited to: the three-terminal FUSE comprises a FUSE1, a FUSE2, a FUSE3, an NMOS tube Q1 and a driving resistor R1; the three-terminal fuse array provides a breakdown protection function for the electronic switch, when any one of the PMOS tube arrays has a breakdown phenomenon, the three-terminal fuse is driven to be started, the internal fuse is heated to be fused, and therefore the load is quickly separated from a working loop, and the breakdown protection function is realized; the breakdown protection of the three-terminal fuse is rapid, the fusing condition can be freely controlled, and the breakdown judgment failure condition caused by the fact that the traditional fuse can only be fused in an overload mode is avoided.

The PMOS transistor driving circuit 4 includes, but is not limited to: a voltage regulator tube Z1, an NMOS tube Q2, current limiting resistors R2 and R3 and a driving resistor R4; because the PMOS tube is adopted as the switching semiconductor device, the drive circuit and the PMOS tube are in a common anode structure, and the on-off control of the PMOS tube array can be realized by controlling whether the NMOS tube Q1 is short-circuited to the ground or not; the driving circuit does not need a boosting unit and performs floating driving, and the whole structure is simple and the cost is low.

The differential current sampling circuit 5 includes, but is not limited to: voltage dividing resistors R5, R6, R7 and R8, proportional amplifying resistors R9, R10, R11 and R12 and an operational amplifier OP1; the overcurrent protection function of the electronic switch can be realized by detecting the total conduction voltage drop of the PMOS tube array and the three-terminal fuse array and inputting the total conduction voltage drop to the MCU controller through the differential amplification circuit; when the conduction voltage drop is detected to be too high, namely the overcurrent condition is indicated, the MCU controller controls to turn off the PMOS tube array, so that overcurrent protection is realized; when the PMOS tube array is switched off, if the current is detected to pass through, the breakdown phenomenon of the PMOS tube is indicated, so that a judgment condition is provided for the breakdown protection function.

It is to be understood that the present invention has been described with reference to certain embodiments and that various changes or equivalents may be substituted for elements thereof without departing from the spirit and scope of the invention as defined by the appended claims. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of the present application are intended to be covered by the present invention.

Claims

1. A high current-carrying electronic switch with breakdown protection function is characterized in that: the electronic switch comprises an electronic switch (1), wherein the electronic switch (1) comprises a PMOS tube array (2), a three-terminal fuse array and drive circuit (3), a PMOS tube drive circuit (4), a differential current sampling circuit (5) and an MCU controller, and the electronic switch (1) is provided with four pins which are respectively a VIN pin, a GND pin, a VO pin and an SGIN pin;

2. The high current-carrying electronic switch with breakdown protection function according to claim 1, wherein the PMOS transistor array (2) comprises a PMOS transistor S1, a PMOS transistor S2, and a PMOS transistor S3; the source electrodes of the PMOS tube S1, the PMOS tube S2 and the PMOS tube S3 are connected together in a short-circuit mode and are connected to the VIN pin; the drains of the PMOS tube S1, the PMOS tube S2 and the PMOS tube S3 are connected together in a short circuit and connected to the input end of the three-terminal fuse array and the driving circuit (3); the grids of the PMOS tube S1, the PMOS tube S2 and the PMOS tube S3 are connected together in a short circuit mode and are connected to the output end of the PMOS tube driving circuit (4).

3. The high current-carrying electronic switch with breakdown protection function according to claim 1, wherein the three-terminal FUSE array and driving circuit (3) comprises a three-terminal FUSE1, a three-terminal FUSE2, a three-terminal FUSE3, an NMOS transistor Q1, a driving resistor R1; the first FUSE ends of the three-terminal FUSE FUSE1, the three-terminal FUSE FUSE2 and the three-terminal FUSE FUSE3 are shorted together to be used as the input end of the three-terminal FUSE array and the driving circuit (3); the second FUSE ends of the three-terminal FUSE FUSE1, the three-terminal FUSE FUSE2 and the three-terminal FUSE FUSE3 are in short circuit together, are used as the output ends of the three-terminal FUSE array and the driving circuit (3) and are connected to the VO pin; heating ends of the three-terminal FUSE FUSE1, the three-terminal FUSE FUSE2 and the three-terminal FUSE FUSE3 are connected together in a short circuit mode and are connected to a drain electrode of the NMOS tube Q1; the grid electrode of the NMOS tube Q1 is connected to a pin 3 of the MCU controller through a driving resistor R1; the source of the NMOS tube Q1 is connected to the GND pin.

4. The high current-carrying electronic switch with the breakdown protection function according to claim 1, wherein the PMOS transistor driving circuit (4) comprises a voltage regulator tube Z1, an NMOS transistor Q2, a current limiting resistor R3, and a driving resistor R4; the cathode of the voltage-stabilizing tube Z1 is connected with one end of a current-limiting resistor R2 and is connected to VIN; the anode of the voltage stabilizing tube Z1 is connected with the other end of the current limiting resistor R2, is connected with one end of the current limiting resistor R3, is used as the output end of the PMOS tube driving circuit (4), and is connected with the grid electrode of the PMOS tube array (2); the other end of the current-limiting resistor R3 is connected with the drain electrode of the NMOS tube Q2; the grid electrode of the NMOS tube Q2 is connected to a pin 2 of the MCU controller through a driving resistor R4; the source of the NMOS transistor Q2 is connected to the GND pin.

5. The high current-carrying electronic switch with breakdown protection function according to claim 1, wherein the differential current sampling circuit (5) comprises a voltage dividing resistor R5, a voltage dividing resistor R6, a voltage dividing resistor R7, a voltage dividing resistor R8, a proportional amplifying resistor R9, a proportional amplifying resistor R10, a proportional amplifying resistor R11, a proportional amplifying resistor R12, an operational amplifier OP1; one end of the divider resistor R5 is connected to the VO pin, and the other end of the divider resistor R5 is connected to the GND pin through the divider resistor R6; one end of the divider resistor R7 is connected to the VO pin, and the other end of the divider resistor R8 is connected to the GND pin; one end of the proportional amplifying resistor R9 is connected to the common end of the voltage dividing resistor R5 and the voltage dividing resistor R6; the other end of the proportional amplifying resistor R9 is connected to the negative input end of the operational amplifier OP1 and is connected to the output end of the operational amplifier OP1 through the proportional amplifying resistor R10; one end of the proportional amplifying resistor R10 is connected to the common end of the voltage dividing resistor R7 and the voltage dividing resistor R8; the other end of the proportional amplifying resistor R10 is connected to the positive input end of the operational amplifier OP1 and is connected to the GND pin through the proportional amplifying resistor R12; the output end of the operational amplifier OP1 is connected to the 4-pin of the MCU controller.

6. The high current-carrying electronic switch with breakdown protection function according to claim 5, wherein the resistance of the voltage dividing resistor R5 is the same as that of the voltage dividing resistor R7.

7. The high current-carrying electronic switch with breakdown protection function according to claim 5, wherein the resistance of the voltage dividing resistor R6 is the same as that of the voltage dividing resistor R8.

8. The high current-carrying electronic switch with breakdown protection function according to claim 5, wherein the proportional amplifying resistor R9 and the proportional amplifying resistor R11 have the same resistance.

9. The high current-carrying electronic switch with breakdown protection function according to claim 5, wherein the proportional amplifying resistor R10 and the proportional amplifying resistor R12 have the same resistance.