CN216056333U

CN216056333U - Communication line self-recovery anti-misconnection protection circuit

Info

Publication number: CN216056333U
Application number: CN202121959636.0U
Authority: CN
Inventors: 刘道容; 杨智伟; 宋志坚; 樊金荣
Original assignee: Shenzhen Sunwell Automation Engineering Co ltd
Current assignee: Shenzhen Sunwell Automation Engineering Co ltd
Priority date: 2021-08-18
Filing date: 2021-08-18
Publication date: 2022-03-15
Anticipated expiration: 2031-08-18

Abstract

The utility model discloses a communication line self-recovery error-proof connection protection circuit, relating to the technical field of communication circuits and comprising a transceiver module, a diode Z1, a diode Z2, a self-recovery fuse F1 connected with a communication line A and a self-recovery fuse F2 connected with a communication line B, the transceiver module is also connected with a power supply anode and a power supply cathode, a communication A wire is connected with the transceiver module through a self-recovery fuse wire F1 and a diode Z1, a communication B wire is connected with the transceiver module through a self-recovery fuse wire F2 and a diode Z2, by connecting or disconnecting the communication a line to the positive electrode of the power supply, the self-recovery fuse F2 switches between a high resistance state and a low resistance state, alternatively, the self-recovery fuse F1 switches between a high resistance state and a low resistance state by connecting or disconnecting the communication B line to the positive electrode of the power supply, thereby completing the protection of the circuit.

Description

Communication line self-recovery anti-misconnection protection circuit

Technical Field

The utility model relates to the technical field of communication circuits, in particular to a self-recovery anti-misconnection protection circuit for a communication line.

Background

At present, a communication line protection circuit only has anti-static protection, and a TVS tube is added at a communication line inlet of a PCBA (printed circuit board assembly) to achieve the aim of static protection.

The product has a power line besides the communication line, and in most cases, the voltage of the power line is much higher than that of the communication line, which can cause the communication circuit to burn out if the communication line and the power line are accidentally contacted.

SUMMERY OF THE UTILITY MODEL

In order to overcome the defects of the prior art, the utility model provides a communication line self-recovery anti-misconnection protection circuit which can solve the problems.

The technical scheme adopted by the utility model for solving the technical problems is as follows:

the communication line self-recovery error-connection-preventing protection circuit is improved in that the communication line self-recovery error-connection-preventing protection circuit comprises a transceiver module, a diode Z1, a diode Z2, a self-recovery fuse wire F1 connected with a communication A line and a self-recovery fuse wire F2 connected with a communication B line, wherein the transceiver module is also connected with a power supply anode and a power supply cathode;

the communication A wire is connected with the transceiver module through a self-recovery fuse F1 and a diode Z1, and the communication B wire is connected with the transceiver module through a self-recovery fuse F2 and a diode Z2;

the self-recovery fuse F2 is switched between a high-resistance state and a low-resistance state by connecting or disconnecting the communication A wire and the positive electrode of the power supply;

alternatively, the self-recovery fuse F1 switches between a high resistance state and a low resistance state by connecting or disconnecting the communication B line to the positive electrode of the power supply, thereby completing the protection of the circuit.

As a further improvement of the above technical solution, the transceiver module includes a chip U1, a resistor R1, and a capacitor C1, and the chip U1 is provided with pins of RO, DI, GND, a, B, and VDD;

the RO pin is used for receiving signals, the DI pin is used for transmitting signals, the GND pin is connected with the negative electrode of a power supply, the A pin is connected with a communication A line through a self-recovery fuse wire F2, the B pin is connected with a communication B line through a self-recovery fuse wire F1, the A pin is connected with the B pin through a resistor R1, the VDD pin is connected with the positive electrode of the power supply, and the VDD pin is connected with the negative electrode of the power supply through a capacitor C1.

As a further improvement of the above technical solution, the cathode of the diode Z1 is connected between the pin F1 and the pin B of the self-recovery fuse, the anode of the diode Z1 is connected to the pin GND, the cathode of the diode Z2 is connected between the pin F2 and the pin a of the self-recovery fuse, and the anode of the diode Z1 and the anode of the diode Z2 are both connected to the cathode of the power supply.

As a further improvement of the above technical solution, the diode Z1 and the diode Z2 are both TVS diodes.

As a further improvement of the above technical solution, the chip U1 includes chips of all communication types.

The utility model has the beneficial effects that: when the communication line is accidentally contacted with the power line or the communication line is wrongly connected to the circuit as a circuit line, the protection circuit can protect the communication circuit and cannot be burnt out; in addition, the circuit of the utility model has simple structure, less material consumption, high practicability and certain popularization and use value, and can save certain cost.

Drawings

The utility model is further illustrated with reference to the following figures and examples.

Fig. 1 is an assembly schematic of the present invention.

Detailed Description

The conception, the specific structure, and the technical effects produced by the present invention will be clearly and completely described below in conjunction with the embodiments and the accompanying drawings to fully understand the objects, the features, and the effects of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments, and those skilled in the art can obtain other embodiments without inventive effort based on the embodiments of the present invention, and all embodiments are within the protection scope of the present invention. In addition, all the connection/connection relations referred to in the patent do not mean that the components are directly connected, but mean that a better connection structure can be formed by adding or reducing connection auxiliary components according to specific implementation conditions. All technical characteristics in the utility model can be interactively combined on the premise of not conflicting with each other.

Referring to fig. 1, the utility model discloses a communication line self-recovery misconnection prevention protection circuit, which comprises a transceiver module 1, a diode Z1, a diode Z2, a self-recovery fuse wire F1 connected with a communication line a and a self-recovery fuse wire F2 connected with a communication line B, wherein the transceiver module 1 is further connected with a power supply anode and a power supply cathode;

the communication A wire is connected with the transceiver module 1 through a self-recovery fuse F1 and a diode Z1, and the communication B wire is connected with the transceiver module 1 through a self-recovery fuse F2 and a diode Z2;

In the above embodiments, the self-recovery fuse is used as F1 and F2 in the circuit, when the short circuit or overload occurs in the circuit, the high current flowing through the self-recovery fuse generates heat to melt the polymer resin, the volume increases rapidly, the high resistance state is formed, and the working current decreases rapidly, thereby limiting and protecting the circuit. After the fault is eliminated, the self-recovery fuse is cooled and crystallized again, the volume shrinks, the conductive particles form a conductive path again, and the self-recovery fuse is recovered to be in a low-resistance state, so that the circuit is protected without manual replacement.

The transceiver module 1 includes a chip U1, a resistor R1, and a capacitor C1, the chip U1 includes chips of all communication types, such as a CAN, a TCPIP, and other types of 485 communication chips, and referring to fig. 1, the chip U1 of the present invention preferably employs an SLM485 chip. The chip U1 is provided with RO, DI, GND, A, B and VDD pins;

The cathode of the diode Z1 is connected between the pin F1 and the pin B, the anode of the diode Z1 is connected with the pin GND, the cathode of the diode Z2 is connected between the pin F2 and the pin A, and the anode of the diode Z1 and the anode of the diode Z2 are both connected with the cathode of the power supply. The diode Z1 and the diode Z2 are TVS diodes.

The protection circuit of the utility model is implemented as follows: when the communication A wire is connected to the positive electrode of the power supply, the diode Z2 is conducted in the reverse direction, and the clamping voltage protects the communication chip U1 from being broken down; meanwhile, the self-recovery protection line F2 enters a high-resistance state due to the fact that large current passes through and the temperature rises, the self-recovery protection line F2 cuts off current on a power line, and the current is prevented from entering the chip U1, so that the diode Z2 and the chip U1 are protected. After the anode of the power supply is disconnected from the communication A line, the self-recovery protection line F2 enters a low-resistance state due to no large current passing through and temperature reduction, and a normal communication signal circuit works normally.

When the communication B wire is connected to the positive electrode of the power supply, the diode Z1 is conducted in the reverse direction, and the clamping voltage protects the communication chip U1 from being broken down; meanwhile, the self-recovery protection line F1 enters a high-resistance state due to the fact that large current passes through and the temperature rises, the self-recovery protection line F1 cuts off current on a power line, the current is prevented from entering the chip U1, and the diode Z1 and the chip U1 are protected. After the positive electrode of the power supply is disconnected from the communication B line, the self-recovery fuse wire F1 enters a low-resistance state due to no large current passing through and temperature reduction, and a normal communication signal circuit works normally.

While the preferred embodiments of the present invention have been illustrated and described, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the utility model as defined by the appended claims.

Claims

1. A communication line self-recovery anti-misconnection protection circuit is characterized by comprising a transceiver module, a diode Z1, a diode Z2, a self-recovery fuse wire F1 connected with a communication A line and a self-recovery fuse wire F2 connected with a communication B line, wherein the transceiver module is also connected with a power supply anode and a power supply cathode;

2. The self-recovery protection circuit of claim 1, wherein the transceiver module comprises a chip U1, a resistor R1 and a capacitor C1, the chip U1 has pins RO, DI, GND, A, B and VDD;

3. The self-recovery mis-connection protection circuit of claim 2, wherein the cathode of the diode Z1 is connected between the pin F1 and the pin B, the anode of the diode Z1 is connected to the pin GND, the cathode of the diode Z2 is connected between the pin F2 and the pin a, and the anode of the diode Z1 and the anode of the diode Z2 are both connected to the cathode of the power supply.

4. The self-recovery mis-connection protection circuit of claim 3, wherein the diode Z1 and the diode Z2 are TVS diodes.

5. The self-recovery protection circuit of claim 2, wherein the chip U1 includes chips of all communication classes.