An input protection module, system and transmission method based on Wiegand interface

Abstract

The present invention discloses an input protection module, system and transmission method based on a Wiegand interface. The input protection module comprises: a first protection unit and a second protection unit; wherein the first output end of the input protection module and the second output end of the input protection module are electrically connected to a first I / O signal and a second I / O signal respectively, and the first input end of the input protection module and the second input end of the input protection module are connected to a data 0 input end of the Wiegand interface and a data 1 input end of the Wiegand interface respectively; wherein the first protection unit and the second protection unit both comprise an input protection circuit; the input protection circuit comprises: a first resistor, a second resistor, an anti-static diode and a first diode; wherein the anti-static diode can provide ESD protection, the first diode is connected to a second voltage source via a second resistor, and is also connected to an I / O port, thereby ensuring single-pass transmission and playing a protective role in reverse connection.

Description

Technical Field

[0001] This invention relates to the field of security technology, and in particular to an input protection module, system, and transmission method based on a Wiegand interface. Background Technology

[0002] Currently, Wiegand interfaces are widely used for data transmission between devices in access control systems. The Wiegand signals output or input through these interfaces are primarily used to connect access control card modules based on Radio Frequency Identification (RFID) technology. With the development of electronic technology, the electronics industry has higher requirements for input protection functions such as electrostatic discharge (ESD), surge suppression, and protection against incorrect connections. Existing technologies have solved the problems of bus leakage and high / low level misjudgment during Wiegand interface transmission and can achieve ESD protection, but their protection against incorrect power supply insertion, reverse insertion, and surge impacts is insufficient, failing to achieve comprehensive input protection. Summary of the Invention

[0003] This invention provides an input protection module, system, and transmission method based on the Wiegand interface, to solve the technical problem that the existing technology cannot provide more comprehensive input protection while ensuring data transmission through the Wiegand interface circuit.

[0004] To address the aforementioned technical problems, embodiments of the present invention provide an input protection module based on a Wiegand interface, comprising: a first protection unit and a second protection unit;

[0005] The first output terminal and the second output terminal of the input protection module are electrically connected to the first I / O signal and the second I / O signal, respectively. The first input terminal and the second input terminal of the input protection module are connected to the data 0 input terminal and the data 1 input terminal of the Wiegand interface, respectively. Both the first protection unit and the second protection unit include an input protection circuit.

[0006] The input protection circuit includes: a first resistor, a second resistor, an anti-static diode, and a first diode;

[0007] The first terminal of the first resistor is electrically connected to the first voltage source;

[0008] The second end of the first resistor is connected to the negative terminal of the first diode, and is also connected to the first input terminal or the second input terminal of the input protection module;

[0009] The positive terminal of the first diode is connected to the first end of the second resistor and the negative terminal of the anti-static diode, and is also connected to the first output terminal or the second output terminal of the input protection module.

[0010] The second terminal of the second resistor is electrically connected to the second voltage source;

[0011] The positive terminal of the anti-static diode is connected to the circuit ground.

[0012] When the first and second input terminals of the input protection module are at a high level, the input protection module is connected to the first or second output terminal via a second voltage source and a second resistor, outputting a high level. Alternatively, when the first and second input terminals of the input protection module are at a low level, the first or second output terminal of the input protection module is pulled down to a low level by a conducting first diode, achieving one-way transmission of the Wiegand interface. Furthermore, in this invention, the positive terminal of the anti-static diode in the input protection circuit is grounded, and the negative terminal of the anti-static diode is connected to the first or second output terminal of the input protection module via a second resistor, providing ESD protection for the receiving I / O signal port. The first diode prevents high voltage backflow to the first or second output terminal of the input protection module, providing more comprehensive input protection for the Wiegand interface.

[0013] Furthermore, the input protection circuit also includes: a second diode, a third resistor, and a capacitor;

[0014] The positive terminal of the second diode is electrically connected to the first voltage source;

[0015] The negative terminal of the second diode is connected to the first end of the first resistor;

[0016] The first end of the third resistor is connected to the first end of the capacitor, and is also connected to the first output end of the input protection module or the second output end of the input protection module;

[0017] The second end of the third resistor is connected to the negative terminal of the antistatic diode and the positive terminal of the first diode;

[0018] The second terminal of the capacitor is connected to the circuit ground.

[0019] Furthermore, the input protection circuit also includes: a Zener diode;

[0020] The negative terminal of the Zener diode is connected to the second terminal of the first resistor and the negative terminal of the first diode;

[0021] The positive terminal of the Zener diode is connected to the circuit ground.

[0022] In this invention, the positive and negative terminals of the second diode are connected to the first voltage source and the first resistor, respectively, to prevent backflow when the first voltage source is mistakenly connected to other ports or the negative terminal of the power supply is mistakenly connected to the positive terminal of the second diode. One end of the third resistor is connected to the I / O port of the input protection module, i.e., the first output port or the second output port, and the other end is connected to the negative terminal of the anti-static diode, further providing ESD protection. In addition, the negative and positive terminals of the Zener diode are connected to the first input terminal or the second input terminal of the input protection module, and the circuit ground, respectively. Through the voltage clamping effect of the Zener diode, surge impact is protected, enabling the input protection module to provide more comprehensive input protection.

[0023] Furthermore, both the first protection unit and the second protection unit include a reverse transmission circuit;

[0024] The reverse transmission circuit includes: a PMOS transistor, an NMOS transistor, a fourth resistor, a fifth resistor, and a third diode;

[0025] The first terminal of the fourth resistor is electrically connected to the second voltage source;

[0026] The second terminal of the fourth resistor is connected to the source of the PMOS transistor;

[0027] The gate of the PMOS transistor is connected to either the first output terminal or the second output terminal of the input protection module.

[0028] The drain of the PMOS transistor is connected to the gate of the NMOS transistor and the first end of the fifth resistor.

[0029] The drain of the NMOS transistor is connected to the negative terminal of the third diode;

[0030] The source of the NMOS transistor is connected to the circuit ground;

[0031] The second terminal of the fifth resistor is connected to the circuit ground;

[0032] The positive terminal of the third diode is connected to either the first input terminal or the second input terminal of the input protection module.

[0033] The reverse transmission circuit of this invention, when receiving a low-level I / O signal at the first or second output terminal of the input protection module, pulls down the gate of the PMOS transistor connected to the first or second output terminal, turning it on. Then, the gate voltage of the NMOS transistor is pulled up by the second voltage source through the on-state PMOS transistor, turning the NMOS transistor on, which in turn turns on the third diode, pulling down the voltage at the first or second input terminal of the input protection module, thus enabling bidirectional transmission. Furthermore, the third diode prevents the NMOS transistor from turning on and forming a loop when the circuit ground is incorrectly connected to the positive power supply or when the first or second input terminal of the input protection module is incorrectly connected to the negative power supply.

[0034] Furthermore, the reverse transmission circuit further includes: a sixth resistor;

[0035] The first end of the sixth resistor is connected to either the first output end of the input protection module or the second output end of the input protection module.

[0036] The second end of the sixth resistor is connected to the gate of the PMOS transistor.

[0037] Furthermore, the input protection circuit also includes: a resettable fuse;

[0038] The first terminal of the self-resetting fuse is connected to the second terminal of the first resistor, the negative terminal of the first diode, and the positive terminal of the third diode;

[0039] The second end of the self-resetting fuse is connected to either the first input end of the input protection module or the second input end of the input protection module.

[0040] The self-resetting fuse of this invention can prevent NMOS transistors from being damaged when they are short-circuited by the power supply for an extended period of time.

[0041] On the other hand, embodiments of the present invention also provide an input protection system based on the Wiegand interface, including: a main control device, an input protection module, and an access control device;

[0042] The main control device is used to provide the input protection module with a first I / O signal and a second I / O signal; and to receive the third I / O signal and a fourth I / O signal provided by the input protection module;

[0043] The input protection module is an input protection module based on the Wiegand interface as described in the embodiments of the present invention;

[0044] The access control device is used to receive a first Wiegand signal sent by the first output terminal and the second output terminal of the input protection module through the Wiegand interface; and to send a second Wiegand signal to the input protection module through the Wiegand interface.

[0045] On the other hand, embodiments of the present invention also provide a transmission method based on a Wiegand interface, the transmission method being applied to an input protection module based on a Wiegand interface as described in embodiments of the present invention, comprising:

[0046] Based on the input protection circuit, the Wiegand signal of the Wiegand interface is read, specifically as follows:

[0047] When the first input terminal of the input protection module receives a high-level signal from the Wiegand interface, the first output terminal of the input protection module is pulled up to a high level by the second voltage source, and outputs a first high-level signal; when the first input terminal of the input protection module receives a low-level signal from the Wiegand interface, the first output terminal of the input protection module is pulled down to a low level by the conducting first diode, and outputs a first low-level signal.

[0048] Alternatively, when the second input terminal of the input protection module receives a high-level signal from the Wiegand interface, the second output terminal of the input protection module is pulled up to a high level by the second voltage source, and outputs a second high-level signal; when the second input terminal of the input protection module receives a low-level signal from the Wiegand interface, the second output terminal of the input protection module is pulled down to a low level by the conducting first diode, and outputs a second low-level signal.

[0049] On the other hand, embodiments of the present invention also provide a transmission method based on a Wiegand interface, the transmission method being applied to an input protection module based on a Wiegand interface as described in embodiments of the present invention, comprising:

[0050] Based on the input protection circuit and the reverse transmission circuit, a Wiegand signal is written to the Wiegand interface, specifically as follows:

[0051] When the first output terminal of the input protection module receives a high-level I / O signal, the first output terminal of the input protection module is pulled up to a high level by the first voltage source, and outputs a third high-level signal; when the first output terminal of the input protection module receives a low-level I / O signal, the gate voltage of the PMOS transistor is pulled up according to the second voltage source of the conducting NMOS transistor to turn on the PMOS transistor, and the first input terminal of the input protection module is pulled down to a low level by the third diode, and outputs a third low-level signal.

[0052] Alternatively, when the second output terminal of the input protection module receives a high-level I / O signal, the second output terminal of the input protection module is pulled up to a high level by the first voltage source, and a fourth high-level signal is output; when the second output terminal of the input protection module receives a low-level I / O signal, the gate voltage of the PMOS transistor is pulled up according to the second voltage source of the turned-on NMOS transistor to turn on the PMOS transistor, and the second input terminal of the input protection module is pulled down to a low level by the third diode, and a fourth low-level signal is output.

[0053] The input protection module in this invention provides more comprehensive input protection for the Wiegand interface, and can also realize one-way transmission or read function for the Wiegand interface through the input protection circuit, and realize write function for the Wiegand interface through the reverse transmission module; this invention provides input protection while ensuring the transmission function. Attached Figure Description

[0054] Figure 1 This is a schematic diagram of the structure of an embodiment of the input protection module based on the Wiegand interface provided by the present invention;

[0055] Figure 2 A schematic diagram of the connection relationship of one embodiment of the input protection circuit provided by the present invention;

[0056] Figure 3 A schematic diagram showing the connection relationship of another embodiment of the input protection circuit provided by the present invention;

[0057] Figure 4 A schematic diagram of the connection relationship of an embodiment of the reverse transmission circuit provided by the present invention;

[0058] Figure 5 A schematic diagram of the connection relationship for another embodiment of the input protection circuit provided by the present invention;

[0059] Figure 6 This is a schematic diagram of an embodiment of the input protection system based on the Wiegand interface provided by the present invention. Detailed Implementation

[0060] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0061] Example 1

[0062] Please refer to Figure 1This is a schematic diagram of the structure of an embodiment of the input protection module based on the Wiegand interface provided by the present invention, including: a first protection unit and a second protection unit.

[0063] The first output terminal and the second output terminal of the input protection module are electrically connected to the first I / O signal and the second I / O signal, respectively. The first input terminal and the second input terminal of the input protection module are connected to the data 0 input terminal and the data 1 input terminal of the Wiegand interface, respectively. Both the first protection unit and the second protection unit include an input protection circuit.

[0064] In this embodiment, the input protection circuit of the first protection unit is taken as an example; the input protection circuit of the second protection unit is the same as the input protection circuit of the first protection module in terms of component selection and connection relationship.

[0065] Please refer to Figure 2 The diagram shows the connection relationship of an embodiment of the input protection circuit provided by the present invention. The input protection circuit includes: a first resistor R1, a second resistor R2, an anti-static diode T1, and a first diode D1.

[0066] The first terminal of the first resistor R1 is electrically connected to the first voltage source WG_5V;

[0067] The second end of the first resistor R1 is connected to the negative terminal of the first diode D1, and also to the first input terminal of the input protection module;

[0068] The positive terminal of the first diode D1 is connected to the first end of the second resistor R2, the negative terminal of the anti-static diode T1, and also to the first output terminal of the input protection module;

[0069] The second terminal of the second resistor R2 is electrically connected to the second voltage source VDD_3V3;

[0070] The positive terminal of the antistatic diode T1 is connected to the circuit ground.

[0071] In this embodiment, for the input protection circuit of the second protection unit, the second end of the first resistor is connected to the negative terminal of the first diode and also to the second input terminal of the input protection module; the positive terminal of the first diode of the input protection circuit of the second protection unit is connected to the first end of the second resistor and the negative terminal of the anti-static diode, and also to the second output terminal of the input protection module.

[0072] In this embodiment, when the first input terminal is high, the second input terminal is pulled up to a high level via the second voltage source VDD_3V3 and the second resistor R2, and the first output terminal of the input protection module outputs a high level. When the first input terminal is low, the first output terminal is pulled down to a low level by the conducting first diode D1, and the first input terminal of the input protection module outputs a low level, completing the one-way signal transmission. Furthermore, the anti-static diode T1 provides ESD protection, and the first diode D1 can be used to prevent backflow caused by incorrect connection.

[0073] Furthermore, the input protection circuit also includes: a second diode, a third resistor R3, and a capacitor C1;

[0074] The positive terminal of the second diode is electrically connected to the first voltage source WG_5V;

[0075] The cathode of the second diode is connected to the first terminal of the first resistor R1;

[0076] The first end of the third resistor R3 is connected to the first end of the capacitor C1, and is also connected to the first output end or the second output end of the input protection module.

[0077] The second end of the third resistor R3 is connected to the negative terminal of the antistatic diode T1 and the positive terminal of the first diode D1;

[0078] The second terminal of capacitor C1 is connected to the circuit ground.

[0079] In this embodiment, for the input protection circuit of the second protection unit, the first end of the third resistor is connected to the first end of the capacitor, and also to the second output end of the input protection module.

[0080] Please refer to Figure 3 This is a schematic diagram showing the connection relationship of another embodiment of the input protection circuit provided by the present invention. The input protection circuit further includes: a Zener diode T5;

[0081] The negative terminal of the Zener diode T5 is connected to the second terminal of the first resistor R1 and the negative terminal of the first diode D1.

[0082] The positive terminal of the Zener diode T5 is connected to the circuit ground.

[0083] In this embodiment, the positive and negative terminals of the second diode are connected to the first voltage source WG_5V and the first resistor R1, respectively, to prevent backflow when the first voltage source WG_5V is mistakenly connected to other ports or the negative terminal of the power supply is mistakenly connected to the positive terminal of the second diode. One end of the third resistor R3 is connected to the I / O port of the input protection module, i.e., the first output port or the second output port, and the other end is connected to the negative terminal of the anti-static diode T1, further providing ESD protection. In addition, the negative and positive terminals of the Zener diode T5 are connected to the first input terminal or the second input terminal of the input protection module, and the circuit ground, respectively. Through the voltage clamping effect of the Zener diode T5, surge impact is protected, enabling the input protection module to provide more comprehensive input protection.

[0084] In this embodiment, the resistance of the first resistor can be 4.7KΩ, the resistance of the second resistor can be 10KΩ, the anti-static diode can be LESD8D3.3CAT5G, the first diode and the second diode can be SS6, the third resistor can be 100R, the capacitor can be 100pF, and the Zener diode can be NC / BV-SMBJ48CA.

[0085] Please refer to Figure 4 , Figure 4 This is a schematic diagram illustrating the connection relationship of an embodiment of the reverse transmission circuit provided by the present invention. Both the first protection unit and the second protection unit include the reverse transmission circuit;

[0086] The reverse transmission circuit includes: PMOS transistor Q1, NMOS transistor Q2, fourth resistor R13, fifth resistor R14, and third diode D6.

[0087] The first terminal of the fourth resistor R13 is electrically connected to the second voltage source;

[0088] The second end of the fourth resistor R13 is connected to the source of the PMOS transistor Q1;

[0089] The gate of the PMOS transistor Q1 is connected to the first output terminal of the input protection module;

[0090] The drain of the PMOS transistor Q1 is connected to the gate of the NMOS transistor Q2 and the first end of the fifth resistor R14;

[0091] The drain of the NMOS transistor Q2 is connected to the negative terminal of the third diode D6;

[0092] The source of the NMOS transistor Q2 is connected to the circuit ground;

[0093] The second terminal of the fifth resistor R14 is connected to the circuit ground;

[0094] The positive terminal of the third diode D6 is connected to the first input terminal of the input protection module.

[0095] In this embodiment, for the input protection circuit of the second protection unit, the gate of the PMOS transistor is connected to the second output terminal of the input protection module, and the anode of the third diode is connected to the second input terminal of the input protection module.

[0096] In this embodiment, when the first or second output terminal of the input protection module receives a low-level I / O signal, the reverse transmission circuit pulls down the gate of the PMOS transistor connected to the first or second output terminal, turning it on. Then, the second voltage source pulls up the gate voltage of the NMOS transistor through the on-state PMOS transistor, turning it on, which in turn turns on the third diode, pulling down the voltage at the first or second input terminal of the input protection module, thus enabling bidirectional transmission. Furthermore, the third diode prevents the NMOS transistor from turning on and forming a loop when the circuit ground is incorrectly connected to the positive power supply or when the first or second input terminal of the input protection module is incorrectly connected to the negative power supply.

[0097] Furthermore, the reverse transmission circuit also includes: a sixth resistor R15;

[0098] The first end of the sixth resistor R15 is connected to the first output end of the input protection module;

[0099] The second end of the sixth resistor R15 is connected to the gate of the PMOS transistor Q1.

[0100] In this embodiment, for the input protection circuit of the second protection unit, the first end of the sixth resistor is connected to the second output end of the input protection module.

[0101] Please refer to Figure 5 This is a schematic diagram showing the connection relationship of another embodiment of the input protection circuit provided by the present invention. The input protection circuit further includes: a resettable fuse F1;

[0102] The first terminal of the self-resetting fuse F1 is connected to the second terminal of the first resistor R1, the negative terminal of the first diode D1, the positive terminal of the third diode D6, and the negative terminal of the Zener diode T5.

[0103] The second end of the self-resetting fuse F1 is connected to the first input end of the input protection module.

[0104] In this embodiment, for the input protection circuit of the second protection unit, the second terminal of the self-resetting fuse is connected to the second input terminal of the input protection module; Figure 5 T5 and Figure 3 T7 in the diagram can be the same Zener diode.

[0105] In this embodiment, the resettable fuse can prevent the NMOS transistor from being damaged when it is shorted by the power supply for an extended period of time.

[0106] In this embodiment, the resistance values ​​of the fourth, fifth, and sixth resistors can be 4.7KΩ, 10KΩ, and 1KΩ, respectively. The PMOS transistor can be AO3401 / SOT23, the NMOS transistor can be VS6640AC, the third diode can be SS16, and the resettable fuse can be SMD0603-005.

[0107] Please refer to Figure 6 This is a schematic diagram of an embodiment of the input protection system based on the Wiegand interface provided by the present invention, which mainly includes: a main control device 601, an input protection module 602, and an access control device 603.

[0108] In this embodiment, the main control device 601 is used to provide the input protection module 602 with a first I / O signal and a second I / O signal; and to receive the third I / O signal and a fourth I / O signal provided by the input protection module 602.

[0109] The input protection module 602 is an input protection module based on the Wiegand interface as described in the embodiments of the present invention.

[0110] The access control device 603 is used to receive a first Wiegand signal sent by the first output terminal and the second output terminal of the input protection module 602 through the Wiegand interface; and to send a second Wiegand signal to the input protection module 602 through the Wiegand interface.

[0111] This invention also provides a transmission method based on a Wiegand interface, which is applied to an input protection module based on a Wiegand interface as described in this invention. The method includes: reading the Wiegand signal of the Wiegand interface according to an input protection circuit; specifically: when the first input terminal of the input protection module receives a high-level signal from the Wiegand interface, the first output terminal of the input protection module is pulled up to a high level by a second voltage source, outputting a first high-level signal; when the first input terminal of the input protection module receives a low-level signal from the Wiegand interface, the first output terminal of the input protection module is pulled down to a low level by a conducting first diode, outputting a first low-level signal.

[0112] In this embodiment, for the second protection unit of the input protection module, when the second input terminal of the input protection module receives a high-level signal from the Wiegand interface, the second output terminal of the input protection module is pulled up to a high level by the second voltage source and outputs a second high-level signal; when the second input terminal of the input protection module receives a low-level signal from the Wiegand interface, the second output terminal of the input protection module is pulled down to a low level by the conducting first diode and outputs a second low-level signal.

[0113] This invention also provides a transmission method based on a Wiegand interface. The transmission method is applied to an input protection module based on a Wiegand interface as described in this invention. The method includes: writing a Wiegand signal to the Wiegand interface according to an input protection circuit and a reverse transmission circuit. Specifically, when the first output terminal of the input protection module receives a high-level I / O signal, the first output terminal of the input protection module is pulled up to a high level by a first voltage source, outputting a third high-level signal; when the first output terminal of the input protection module receives a low-level I / O signal, the gate voltage of the PMOS transistor is pulled up according to the second voltage source of the conducting NMOS transistor to turn on the PMOS transistor, and the first input terminal of the input protection module is pulled down to a low level by a third diode, outputting a third low-level signal.

[0114] In this embodiment, for the second protection unit of the input protection module, when the second output terminal of the input protection module receives a high-level I / O signal, the second output terminal of the input protection module is pulled up to a high level by the first voltage source, and a fourth high-level signal is output; when the second output terminal of the input protection module receives a low-level I / O signal, the gate voltage of the PMOS transistor is pulled up according to the second voltage source of the turned-on NMOS transistor to turn on the PMOS transistor, and the second input terminal of the input protection module is pulled down to a low level by the third diode, and a fourth low-level signal is output.

[0115] In this embodiment, the input protection module provides more comprehensive input protection for the Wiegand interface, and can also realize one-way transmission or read function for the Wiegand interface through the input protection circuit, and realize write function for the Wiegand interface through the reverse transmission module; the present invention provides input protection while ensuring the transmission function.

[0116] When the first and second input terminals of the input protection module are at a high level, the input protection module is connected to the first or second output terminal via a second voltage source and a second resistor, outputting a high level. Alternatively, when the first and second input terminals of the input protection module are at a low level, the first or second output terminal of the input protection module is pulled down to a low level by a conducting first diode, achieving one-way transmission of the Wiegand interface. Furthermore, in this invention, the positive terminal of the anti-static diode in the input protection circuit is grounded, and the negative terminal of the anti-static diode is connected to the first or second output terminal of the input protection module via a second resistor, providing ESD protection for the receiving I / O signal port. The first diode prevents high voltage backflow to the first or second output terminal of the input protection module, providing more comprehensive input protection for the Wiegand interface.

[0117] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. In particular, it should be noted that any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention for those skilled in the art.

Claims

1. An input protection module based on a Wiegand interface, characterized in that: include: a first protection unit and a second protection unit; Wherein, the first output end of the input protection module and the second output end of the input protection module are electrically connected to the first I / O signal and the second I / O signal respectively, and the first input end of the input protection module and the second input end of the input protection module are connected to the data 0 input end of the Wiegand interface and the data 1 input end of the Wiegand interface respectively; wherein the first protection unit and the second protection unit both include an input protection circuit; The input protection circuit comprises: a first resistor, a second resistor, an anti-static diode and a first diode; The first end of the first resistor is electrically connected to a first voltage source; The second end of the first resistor is connected to the cathode of the first diode, and is also connected to the first input end of the input protection module or the second input end of the input protection module; The anode of the first diode is connected to the first end of the second resistor and the cathode of the anti-static diode, and is also connected to the first output end of the input protection module or the second output end of the input protection module; The second end of the second resistor is electrically connected to a second voltage source; The positive electrode of the anti-static diode is connected to the circuit ground.

2. The input protection module based on the Wiegand interface according to claim 1, characterized in that: The input protection circuit further includes: a second diode, a third resistor and a capacitor; An anode of the second diode is electrically connected to the first voltage source; The cathode of the second diode is connected to the first end of the first resistor; The first end of the third resistor is connected to the first end of the capacitor, and is also connected to the first output end of the input protection module or the second output end of the input protection module; The second end of the third resistor is connected to the cathode of the anti-static diode and the anode of the first diode; The second end of the capacitor is connected to the circuit ground.

3. The input protection module based on the Wiegand interface as claimed in claim 1, characterized in that: The input protection circuit further includes: a voltage regulator tube; The cathode of the voltage regulator tube is connected to the second end of the first resistor and the cathode of the first diode; The positive electrode of the voltage regulator tube is connected to the circuit ground.

4. The input protection module based on the Wiegand interface according to claim 1, characterized in that: The first protection unit and the second protection unit both include a reverse transmission circuit; Wherein, the reverse transmission circuit includes: a PMOS tube, an NMOS tube, a fourth resistor, a fifth resistor, and a third diode; The first end of the fourth resistor is electrically connected to the second voltage source; The second end of the fourth resistor is connected to the source of the PMOS tube; The gate of the PMOS tube is connected to the first output terminal of the input protection module or the second output terminal of the input protection module; The drain of the PMOS tube is connected to the gate of the NMOS tube and the first end of the fifth resistor; The drain of the NMOS tube is connected to the cathode of the third diode; The source of the NMOS tube is connected to the circuit ground; The second end of the fifth resistor is connected to the circuit ground; An anode of the third diode is connected to the first input terminal of the input protection module or the second input terminal of the input protection module.

5. The input protection module based on the Wiegand interface as claimed in claim 4, characterized in that: The reverse transmission circuit further includes: a sixth resistor; The first end of the sixth resistor is connected to the first output end of the input protection module or the second output end of the input protection module; The second end of the sixth resistor is connected to the gate of the PMOS tube.

6. The input protection module based on the Wiegand interface as claimed in claim 4, characterized in that: The input protection circuit further includes: a resettable fuse; The first end of the resettable fuse is connected to the second end of the first resistor, the cathode of the first diode and the anode of the third diode; The second end of the resettable fuse is connected to the first input end of the input protection module or the second input end of the input protection module.

7. An input protection system based on Wiegand interface, characterized in that: include: Main control device, input protection module and access control device; The main control device is used to provide the first I / O signal and the second I / O signal to the input protection module; and is used to receive the third I / O signal and the fourth I / O signal provided by the input protection module; The input protection module is an input protection module based on a Wiegand interface as described in any one of claims 4 to 6; The access control device is used to receive a first Wiegand signal sent by a first output end of the input protection module and a second output end of the input protection module through a Wiegand interface; and is used to send a second Wiegand signal to the input protection module through the Wiegand interface.

8. A transmission method based on Wiegand interface, characterized in that: The transmission method is applied to the input protection module based on the Wiegand interface as claimed in any one of claims 1 to 6, comprising: According to the input protection circuit, the Wiegand signal of the Wiegand interface is read, specifically: When the first input end of the input protection module receives a high level signal of the Wiegand interface, the first output end of the input protection module is pulled up to a high level by the second voltage source, and a first high level signal is output; when the first input end of the input protection module receives a low level signal of the Wiegand interface, the first output end of the input protection module is pulled down to a low level by the turned-on first diode, and a first low level signal is output; Alternatively, when the second input end of the input protection module receives a high-level signal of the Wiegand interface, the second output end of the input protection module is pulled up to a high level by the second voltage source, and a second high-level signal is output; when the second input end of the input protection module receives a low-level signal of the Wiegand interface, the second output end of the input protection module is pulled down to a low level by the conductive first diode, and a second low-level signal is output.

9. A transmission method based on Wiegand interface, characterized in that: The transmission method is applied to the input protection module based on the Wiegand interface as claimed in any one of claims 4 to 6, comprising: According to the input protection circuit and the reverse transmission circuit, the Wiegand signal is written to the Wiegand interface, specifically: When the first output end of the input protection module receives a high-level I / O signal, the first output end of the input protection module is pulled up to a high level by the first voltage source, and a third high-level signal is output; when the first output end of the input protection module receives a low-level I / O signal, the gate voltage of the PMOS tube is pulled up according to the second voltage source of the turned-on NMOS tube to turn on the PMOS tube, and the first input end of the input protection module is pulled down to a low level by the third diode, and a third low-level signal is output; Alternatively, when the second output end of the input protection module receives a high-level I / O signal, the second output end of the input protection module is pulled up to a high level by the first voltage source, and a fourth high-level signal is output; when the second output end of the input protection module receives a low-level I / O signal, the gate voltage of the PMOS tube is pulled up according to the second voltage source of the turned-on NMOS tube to turn on the PMOS tube, and the second input end of the input protection module is pulled down to a low level by the third diode, and a fourth low-level signal is output.

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