Key switch

Abstract

The utility model discloses a key switch, which relates to the technical field of switches and comprises a four-pin protection switch, a current-limiting resistor and an anti-static impact protection bidirectional diode. A first pin and a third pin of the four-pin protection switch are connected and then connected with the current-limiting resistor, and the current-limiting resistor is connected with a first pin of the bidirectional diode; the second pin and the fourth pin of the four-pin protection switch are connected and then connected with the second pin of the bidirectional diode. According to the utility model, by introducing the bidirectional diode, the resistance of the key switch to electrostatic discharge is effectively improved, and the risk of circuit damage caused by electrostatic impact is reduced. The current-limiting resistor is added to limit the current passing through the circuit, so that the circuit fault caused by overlarge current is prevented, and the stability of the circuit is further improved. And all elements are welded on the circuit board, so that the assembling process of the circuit is simplified, and subsequent maintenance and replacement are also facilitated.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of switch, specifically point to a key switch. BACKGROUND

[0002] In the current electronic equipment, as the basic interface of user and equipment interaction, the stability and reliability of key switch are very important. However, electronic equipment often faces the transient voltage impact such as electrostatic discharge (ESD) in the use process, which can cause switch damage or affect the normal operation of the equipment. Therefore, it is particularly important to design a kind of key switch that can effectively resist static impact and protect the safety of circuit. SUMMARY

[0003] The utility model aims at providing a kind of key switch, to solve the problem that key switch is vulnerable to static impact in prior art, by introducing four foot protection switch, current limiting resistor and the bidirectional diode of anti-static impact protection, the effective protection to key switch is realized.

[0004] To solve the above technical problem, the technical scheme provided by the utility model is as follows: a kind of key switch, including four foot protection switch, current limiting resistor and the bidirectional diode of anti-static impact protection;

[0005] The first pin and the third pin of the four foot protection switch are connected after connecting the current limiting resistor, and the first pin of the bidirectional diode is connected;The second pin and the fourth pin of the four foot protection switch are connected after connecting the second pin of the bidirectional diode.

[0006] Further, the first pin of the bidirectional diode receives input voltage signal, and the second pin of the bidirectional diode outputs voltage signal.

[0007] Further, the four foot protection switch, current limiting resistor and bidirectional diode are all welded on the circuit board.

[0008] The utility model has the advantages compared with prior art: the utility model introduces bidirectional diode, effectively improves the resistance ability of key switch to electrostatic discharge, reduces the risk of circuit damage caused by static impact. The addition of current limiting resistor limits the current passing through the circuit, prevents the circuit failure caused by excessive current, and further improves the stability of the circuit. All components are welded on the circuit board, which not only simplifies the assembly process of the circuit, but also facilitates subsequent maintenance and replacement. BRIEF DESCRIPTION OF DRAWINGS

[0009] Figure 1 It is the structure diagram of the utility model a kind of key switch Figure 1 .

[0010] Figure 2The utility model relates to a structure diagram of a key switch Figure 2 .

[0011] Figure 3 The utility model relates to a circuit principle diagram of a key switch.

[0012] As shown in the figure: 1, four feet protection switch, 2, current -limiting resistance, 3, two -way diode, 4, circuit board. DETAILED DESCRIPTION

[0013] In the description of the utility model, it is understood that the orientation or positional relation indicated by the terms "up", "down", "front", "back", "left", "right", "inner", "outer", "vertical", "circumferential" and the like is the orientation or positional relation based on the orientation or positional relation shown in the drawings, and is only for the convenience of describing the utility model and simplifying the description, and therefore cannot be understood as a limitation on the utility model.

[0014] In the description of the utility model, "first feature", "second feature" can include one or more features. In addition, the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features limited by "first", "second" can explicitly or implicitly include one or more features.

[0015] In the utility model, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood in a broad sense, for example, can be fixedly connected, can be detachably connected or integrally connected, can be mechanically connected, can be electrically connected, can be directly connected, can be indirectly connected through an intermediate medium, and can be the communication between two elements. For ordinary skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.

[0016] The utility model will be further described in detail below in combination with the drawings.

[0017] In combination with the drawings Figures 1-3 The utility model is introduced in detail.

[0018] A kind of key switch, specifically including following component parts:

[0019] Four feet protection switch 1: with four pins, wherein first pin and third pin are connected with each other;Second pin and fourth pin are connected with each other. This design enhances the electrical connection stability of switch, and helps to disperse current, improves anti electrostatic shock capacity.

[0020] The current-limiting resistor 2 is connected between the first pin and the third pin connection point of the four-pin protection switch 1 and the first pin of the bidirectional diode 3.

[0021] The bidirectional diode 3 is used to provide anti-static shock protection. The first pin receives an input voltage signal from the current-limiting resistor 2, and the second pin outputs a protected voltage signal to the second pin and the fourth pin connection point of the four-pin protection switch 1. The bidirectional diode 3 can quickly respond to and absorb the transient voltage generated by electrostatic discharge, thereby protecting the circuit from damage.

[0022] The first pin of the bidirectional diode 3 serves as an input terminal to receive a voltage signal from an external power source, and the second pin serves as an output terminal to provide a protected stable voltage signal to a subsequent circuit.

[0023] The four-pin protection switch 1, the current-limiting resistor 2, and the bidirectional diode 3 are all fixedly installed on the circuit board 4 by welding, ensuring the firmness and reliability of the circuit connection.

[0024] The specific implementation process of the key switch of the utility model is as follows:

[0025] The first pin of the ESD bidirectional diode 3 inputs a voltage signal, which is limited by the current-limiting resistor 2 (R1) and provided to the third pin of the four-pin protection switch 1. Since the first pin and the third pin of the four-pin protection switch 1 are connected, and the second pin and the fourth pin are connected, at this time, the key of the four-pin protection switch 1 is pressed, so that the first pin and the second pin of the four-pin protection switch 1 are connected, and then the fourth pin of the four-pin protection switch 1 has a voltage signal, which is then output through the second pin of the bidirectional diode 3.

[0026] The above describes the utility model and its implementation mode, which is not limited. The drawings shown are only one of the embodiments of the utility model, and the actual structure is not limited thereto. In summary, if a person skilled in the art is inspired thereby, without departing from the creative purpose of the utility model, without creative design, similar structure modes and embodiments of the technical solutions are designed, which should belong to the protection scope of the utility model.

Claims

1. A key switch characterized by: The bidirectional diode is connected with the four-pin protection switch, the current-limiting resistor and the anti-static impact protection. The first pin and the third pin of the four-pin protection switch are connected with the current-limiting resistor, and the current-limiting resistor is connected with the first pin of the bidirectional diode; the second pin and the fourth pin of the four-pin protection switch are connected with the second pin of the bidirectional diode.

2. A key switch according to claim 1, wherein: The first pin of the bidirectional diode receives an input voltage signal, and the second pin of the bidirectional diode outputs a voltage signal.

3. A key switch according to claim 2, wherein: The four-pin protection switch, the current-limiting resistor and the bidirectional diode are all welded on a circuit board.

Images