CN214409938U

CN214409938U - Touch screen anti-static interference circuit, touch screen and handle

Info

Publication number: CN214409938U
Application number: CN202022650272.XU
Authority: CN
Inventors: 廖武华; 陈虎; 冯红涛; 王强; 樊光民; 张涛
Original assignee: Chunmi Technology Shanghai Co Ltd
Current assignee: Chunmi Technology Shanghai Co Ltd
Priority date: 2020-11-16
Filing date: 2020-11-16
Publication date: 2021-10-15
Anticipated expiration: 2030-11-16

Abstract

The embodiment of the utility model discloses antistatic interference circuit of touch-sensitive screen, touch-sensitive screen and handle, touch-sensitive screen have display module and host system, the circuit includes: first antistatic module, second antistatic module, wherein: the first antistatic module is connected with the voltage input interface of the display module and used for absorbing the electrostatic interference of the voltage input interface and guiding the electrostatic interference to the ground. The second anti-static module is arranged between the first communication interface of the display module and the second communication interface of the main control module and used for absorbing and guiding the static interference between the first communication interface and the second communication interface to the ground. The first communication interface is connected with the second communication interface and used for realizing communication between the display module and the main control module. Through setting up first antistatic module and second antistatic module to reach the voltage input interface and the communication interface anti electrostatic interference ability and the anti EFT interference ability of reinforcing display module.

Description

Touch screen anti-static interference circuit, touch screen and handle

Technical Field

The utility model relates to an antistatic field especially relates to a touch-sensitive screen anti-static interference circuit, touch-sensitive screen and handle.

Background

Along with the development of society, the household electrical appliances industry uses touch control mode more and more, and touch control mode replaces traditional mechanical button control gradually, and touch control mode has all fine promotion to the control panel roughness of product, waterproof nature and life-span.

The control panel of the current household appliance products adopts more and more OLED touch screens in touch control modes, and the OLED touch screens in the touch control modes have the advantages of rich display contents, diversified touch control selections, simple structure and the like. However, the touch function integrated on the OLED touch screen has weak resistance to electrostatic interference, and may easily crash or trigger by mistake when the OLED touch screen is subjected to an electrostatic test of electromagnetic compatibility EMC or touched by a large amount of human static electricity.

SUMMERY OF THE UTILITY MODEL

Therefore, the antistatic interference circuit and the handle for the touch screen are needed to solve the problems, and the purpose of the application is to achieve the effect of enhancing the antistatic interference capability of the touch screen by adding the electrostatic discharge tube at the communication interface and the voltage input interface.

In a first aspect, the present application provides an anti-electrostatic interference circuit for a touch screen, the touch screen having a display module and a main control module, the circuit comprising:

the first antistatic module is connected with the voltage input interface of the display module and used for absorbing and guiding the electrostatic interference of the voltage input interface to the ground; and

the second anti-static module is arranged between the first communication interface of the display module and the second communication interface of the main control module and is used for absorbing and guiding the static interference between the first communication interface and the second communication interface to the ground;

the first communication interface is connected with the second communication interface and is used for realizing communication between the display module and the main control module.

In a second aspect, the present application provides a touch screen, the touch screen is an OLED display screen, and the touch screen includes the touch screen anti-electrostatic interference circuit.

In a third aspect, the present application provides a handle, including a housing and the touch screen, wherein an accommodating space is provided in the housing, and the touch screen is placed in the accommodating space.

Adopt the embodiment of the utility model provides a, following beneficial effect has:

adopt the utility model discloses a touch-sensitive screen anti-static interference circuit, touch-sensitive screen and handle, through setting up first antistatic module, can absorb and lead-in the ground with the electrostatic interference of display module's voltage input interface, the realization is to the absorption of the electrostatic interference of display module's voltage input kneck, through setting up the second antistatic module, can absorb and lead-in the ground with the electrostatic interference of display module's communication interface and host system's communication interface, the realization is to the absorption of the electrostatic interference of display module's communication interface and host system's communication kneck, thereby reach the effect of reinforcing circuit's anti-static interference ability. In addition, the arrangement of the first antistatic module and the second antistatic module can also enhance the anti-EFT interference capability of the circuit.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Wherein:

FIG. 1 is a block diagram of an embodiment of an anti-electrostatic interference circuit for a touch panel;

FIG. 2 is a block diagram of an embodiment of an anti-electrostatic interference circuit for a touch panel;

FIG. 3 is a schematic circuit diagram of an anti-electrostatic interference circuit of a touch panel according to an embodiment;

FIG. 4 is a schematic diagram of an embodiment of a touch screen;

FIG. 5 is a schematic view of the housing of the handle in one embodiment;

FIG. 6 is a schematic diagram of a touch screen mounted on the housing of the handle in one embodiment.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

In the embodiment of the present application, an anti-electrostatic interference circuit for a touch screen is provided, as shown in fig. 1, the touch screen has a display module 102 and a main control module 104. The circuit comprises: a first antistatic module 101 and a second antistatic module 104. The first anti-static module 101 is connected to the voltage input interface 201 of the display module 102, and is configured to absorb and guide the electrostatic interference of the voltage input interface 201 to the ground. The second anti-static module 104 is disposed between the first communication interface 202 of the display module 102 and the second communication interface 203 of the main control module 103, and is configured to absorb and guide static interference between the first communication interface 202 and the second communication interface 203 to the ground. The first communication interface 202 is connected to the second communication interface 203, and is configured to implement communication between the display module 102 and the main control module 103.

In the embodiment of the present application, the display module 102 is an OLED touch screen. An OLED (organic light-emitting diode) is a display technology that uses an organic polymer material as a semiconductor material in the light-emitting diode. The OLED display technology has the self-luminous characteristic, adopts a very thin organic material coating and a glass substrate, and when current flows, the organic materials can emit light, and the OLED display screen has a large visual angle and can save electric energy. The OLED display technology is widely used in mobile phones, digital video cameras, DVD players, Personal Digital Assistants (PDAs), notebook computers, car stereos, and televisions.

The main control module 104 is a main control chip, and may be a central processing unit or a DSP processor, and the main control module 104 is connected to the display module 102, so as to implement communication between the main control chip and the OLED touch screen.

The touch screen is also called as touch screen or touch panel, and is an inductive liquid crystal display device capable of receiving input signals of a touch head and the like, when a graphical button on the screen is touched, a touch feedback system on the screen can drive various connecting devices according to a pre-programmed program, so that the touch screen can be used for replacing a mechanical button panel, and vivid video and audio effects can be produced by a liquid crystal display picture.

In the embodiment of the application, an anti-static interference circuit for a touch screen is provided, by arranging a first anti-static module 101, the static interference of a voltage input interface 201 of a display module 102 can be absorbed and guided to the ground, the static interference at the voltage input interface 201 of the display module 102 can be eliminated, by arranging a second anti-static module 104, the static interference of a communication interface of the display module 102 and a communication interface of a main control module 103 can be absorbed and guided to the ground, the static interference at the communication interface of the display module 102 and the communication interface of the main control module 103 can be eliminated, and the effect of enhancing the anti-static interference capability of the display screen is achieved. In addition, by arranging the first antistatic module 101, the EFT interference of the voltage input interface 201 of the display module 102 can be introduced into the ground, so that the absorption of the EFT interference at the voltage input interface 201 of the display module 102 is realized, by arranging the second antistatic module 104, the EFT interference of the communication interface of the display module 102 and the EFT interference of the communication interface of the main control module 103 can be introduced into the ground, so that the absorption of the EFT interference at the communication interface of the display module 102 and the communication interface of the main control module 103 is realized, and the effect of enhancing the EFT interference resistance of the display screen is achieved.

In one embodiment, as shown in fig. 2 and 3, the first antistatic module 101 includes a first static discharge tube ESD1 and a second static discharge tube ESD 2. A first terminal of the first ESD1 is connected to the voltage input interface 201, and a second terminal of the first ESD1 is grounded. A first terminal of the second ESD2 is connected to the voltage input interface 201, and a second terminal of the second ESD2 is grounded.

The second anti-static module 104 includes a third electrostatic discharge tube ESD3 and a fourth electrostatic discharge tube ESD 4. A first end of the third ESD3 is connected to the first communication interface 202 and the second communication interface 203, respectively, and a second end of the third ESD3 is grounded; the first end of the fourth ESD4 is connected to the first communication interface 202 and the second communication interface 203, and the second end of the fourth ESD4 is grounded.

An electrostatic discharge (ESD) transistor is an electrostatic impedance device or an electrostatic protection element specially used in electronic consumer and digital products: the response speed of the ESD tube with the voltage range of less than 24V and the interelectrode capacitance of less than 2.5PF is less than 1ns, and the ESD tube has extremely low leakage current. The working principle of the ESD tube is that in the normal working process of the electric appliance, the ESD tube only shows the capacitive reactance characteristic with extremely low capacitance value (generally less than 5PF), can not influence the normal electric appliance characteristic, and can not influence the signal and data transmission of the electronic product; when the overvoltage at two ends of the ESD tube reaches a preset breakdown voltage, the ESD tube reacts quickly (nanosecond level), and the leakage current between electrodes is amplified to pass through by geometric level, so that the interference and influence of static electricity on the circuit characteristics are absorbed and weakened. Meanwhile, due to the particularity of the structural material of the ESD tube, the ESD tube usually absorbs and dissipates static electricity, namely, shows a charging and discharging process, so that the equipment is protected from static electricity, and the ESD tube in the equipment is not easy to age and damage. The ESD tube has the advantages of high response speed (less than 0.5ns), low capacitance, low on-state voltage, high integration degree, small volume and easy installation, can simultaneously realize the protection of a plurality of data lines, and is the most ideal high-frequency data protection device in the industry. The ESD tube is mainly applied to electrostatic protection of various communication interfaces, such as USB, HDMI, RS485, RS232, VGA, RJ11, RJ45, BNC, SIM, SD and the like. Meanwhile, the ESD electrostatic protection components are packaged in a diversified manner from single-path SOD-323 to multiple-path SOT-23, SOT23-6L, QFN-10 and the like, and a circuit design engineer can select ESD pipes packaged differently according to the layout and the interface type of a circuit board.

In one embodiment, the display module 102 includes a voltage input interface 201 and a first communication interface 202. Wherein, the voltage input interface 201 includes: the first anti-static module 101 is connected to the power supply voltage input interface and the driving voltage input interface.

In an embodiment, the first anti-static module 101 further includes a first capacitor C14 and a second capacitor C19, the first capacitor C14 is connected in parallel with the first ESD1 to form a first parallel branch, a first end of the first parallel branch is connected to the power supply voltage input interface, and a second end of the first parallel branch is grounded. The second capacitor C19 and the second electrostatic discharge tube ESD2 are connected in parallel to form a second parallel branch, a first end of the second parallel branch is connected to the driving voltage input interface, and a second end of the second parallel branch is grounded. The capacitance of the first capacitor C14 is 1 UF; the capacitance of the second capacitor C19 is 10UF in size.

The driving voltage of the driving voltage input interface is 12V and is used for driving the OLED touch screen to emit light. And the power supply voltage input interface provides power supply for the OLED touch screen wafer.

In one embodiment, as shown in fig. 3, the voltage input interface 201 further includes an IREF interface, a VCOMH interface, and a VSL interface, and the IREF interface, the VCOMH interface, and the VSL interface are electrically connected to the first antistatic module 101. The IREF interface is used for adjusting current reference brightness; the VCOMH interface is used for outputting high level voltage; the VSL interface functions to output a low level reference.

In one embodiment, the first anti-static module 101 includes a third resistor R21, a fourth resistor R19, a first diode D1, a second diode D2, and a fourth capacitor C16. One end of the third resistor R21 is connected with the IREF interface, and the other end of the third resistor R21 is grounded. One end of the fourth resistor R19 is connected to the VSL interface, the other end of the fourth resistor R19 is connected to the anode of the first diode D1, the cathode of the first diode D1 is connected to the anode of the second diode D2, and the cathode of the second diode D2 is grounded. One end of the fourth capacitor C16 is connected to the VCOMH interface, and the other end of the fourth capacitor C16 is grounded. Wherein the display module 102 is provided with two VCOMH interfaces.

The resistance value of the third resistor R21 is 510k omega; the fourth resistor R19 is a chip resistor 39R; the capacitance of the fourth capacitor C16 is 2.2 PF; the first diode D1 and the second diode D2 are both diodes of type B0530W.

Furthermore, voltage fluctuation interference caused by electrostatic interference or EFT interference affects a module power supply of the OLED touch screen, and the power supply is interfered by the voltage fluctuation to cause the OLED touch screen touch module to be halted or to have communication fault, or to be judged by mistake to change the working mode. When a touch module power supply of the OLED touch screen is subjected to electrostatic interference or EFT interference, the first electrostatic discharge tube ESD1 and the second electrostatic discharge tube ESD2 directly conduct interference to a circuit ground line to achieve electrostatic interference absorption at a reaction speed of 0.5ns through a self short circuit state, and when the electrostatic interference voltage or the EFT interference voltage is reduced to be lower than a voltage fixed by the first electrostatic discharge tube ESD1 and the second electrostatic discharge tube ESD2, the self short circuit state of the first electrostatic discharge tube ESD1 and the second electrostatic discharge tube ESD2 is relieved, so that the voltage is stabilized. The arrangement of the first electrostatic discharge tube ESD1 and the second electrostatic discharge tube ESD2 enhances the anti-electrostatic interference capability and the anti-EFT interference capability of the voltage input interface 201 of the OLED touch screen.

In one embodiment, the first communication interface 202 includes: the TD0 interface and the TD1 interface, the TD0 interface is connected with the first end of the third electrostatic discharge tube ESD3 through a first resistor R16; the TD1 interface is connected with the first end of the fourth ESD4 through a second resistor R17. The TD0 interface and the TD1 interface are communication interfaces between the touch control portion of the display module 102 and the main control module 103.

In one embodiment, the second communication interface 203 comprises an IO19 interface and an IO18 interface; the IO19 interface is connected with the TD0 interface through a first resistor R16, and the IO19 interface is further connected with a first end of a third electrostatic discharge tube ESD 3. The IO18 interface is connected with the TD1 interface through a second resistor R17, and the IO19 interface is further connected with a first end of a fourth electrostatic discharge tube ESD 4. The resistance values of the first resistor R16 and the second resistor R17 are 100k omega resistors.

Further, both electrostatic interference and EFT interference may cause a power supply of the display module 102 to have transient voltage fluctuation, based on chain reaction, a communication interface between the display module 102 (i.e., a touch module of the OLED touch screen) and the main control module 103 may also have voltage fluctuation of ms level, because the communication frequency of the display module 102 is at M level, communication is easily disturbed by voltage fluctuation, and finally communication distortion or even failure is caused, the display module 102 cannot obtain a correct instruction, and the display module 102 may be halted or a working mode is changed. When the communication interfaces of the display module 102 and the main control module 103 are subjected to electrostatic interference or EFT interference, the third ESD3 and the fourth ESD4 directly lead the interference to the ground through their own short circuit state at a fixed voltage value at a reaction speed of 0.5ns to absorb the electrostatic interference, and when the electrostatic interference voltage drops below the fixed voltage of the third ESD3 and the fourth ESD4, the third ESD3 and the fourth ESD4 relieve their own short circuit state, thereby achieving the purpose of enhancing the electrostatic interference resistance and the EFT interference resistance of the communication interfaces of the display module 102 and the main control module 103.

In one embodiment, the circuit further includes a third capacitor EC1, the first terminal of the third capacitor EC1 being connected to the driving voltage input interface. The first terminal of the third capacitor EC1 is also connected to the first terminal of the second parallel branch. The second terminal of the third capacitor EC1 is grounded.

In one embodiment, the third capacitor EC1 is an electrolytic capacitor. When the voltage input interface 201 of the display module 102 is subjected to electrostatic interference, the EC1 electrolytic capacitor EC1 regulates the ripple of the power supply through self charging and discharging. The electrolytic capacitor is one kind of capacitor, the metal foil is positive electrode (aluminum or tantalum), the oxide film (aluminum oxide or tantalum pentoxide) close to the metal with the positive electrode is dielectric, and the cathode is composed of conductive material, electrolyte (the electrolyte can be liquid or solid) and other materials. Meanwhile, the anode and the cathode of the electrolytic capacitor can not be connected in a wrong way. Aluminum electrolytic capacitors can be classified into four categories: lead type aluminum electrolytic capacitor, horn type aluminum electrolytic capacitor, bolt type aluminum electrolytic capacitor and solid state aluminum electrolytic capacitor. The electrolytic capacitor is characterized in that: the capacitance per unit volume is very large, and is dozens to hundreds of times larger than other types of capacitors; the rated capacity can be very large, and tens of thousands of UF and even F can be easily realized; the price has overwhelming advantages compared with other types of capacitors, because the constituent materials of the electrolytic capacitor are common industrial materials, and the equipment for manufacturing the electrolytic capacitor is common industrial equipment, the electrolytic capacitor can be produced in large scale, and the cost is relatively low.

The polar electrolytic capacitor generally plays the roles of power filtering, decoupling, signal coupling and time constant setting, DC blocking and the like in a power circuit or an intermediate frequency and low frequency circuit. Electrolytic capacitors are generally not used in ac power circuits. When the filter capacitor is used in a direct current power supply circuit, the anode (positive electrode) of the filter capacitor is connected with the positive end of a power supply voltage, and the cathode (negative electrode) of the filter capacitor is connected with the negative end of the power supply voltage, so that the anode and the cathode cannot be connected reversely, otherwise, the capacitor can be damaged.

Nonpolar electrolytic capacitors are commonly used in speaker divider circuits, television S correction circuits, and starting circuits for single-phase motors. The non-polar electrolytic capacitor is widely applied to household appliances and various electronic products, and has a large capacity range, generally 1-33000 UF, and a rated working voltage range of 6.3-700V. Its disadvantages are high dielectric loss and capacity error (maximum allowable deviation is + 100%, -20%), poor high-temp resistance, long storage time and easy failure.

The present application further provides a touch screen 105, as shown in fig. 4, where the touch screen 105 includes the touch screen anti-electrostatic interference circuit of any of the embodiments described above.

The application also provides a handle, uses on household electrical appliances, for example use on the kettle that has the touch-sensitive screen, is provided with the touch-sensitive screen on the handle of kettle, and the touch-sensitive screen can show the temperature in the kettle, information such as heating time, through the steerable kettle mode of touch-sensitive screen. The working modes of the kettle comprise: and working modes of boiling water, preserving heat, boiling tea and the like.

As shown in fig. 5 and 6, the handle includes a touch screen 105 and a housing 106, an accommodating space is provided in the housing 106, the touch screen 105 is placed in the accommodating space, and the touch screen 105 is fixed in the accommodating space by a snap. Installing the touch screen 105 on the handle improves the antistatic and EFT resistance of the handle, which in turn improves the service life of the handle.

The technical features of the above embodiments can be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the above embodiments are not described, but should be considered as the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present application. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. The utility model provides a touch-sensitive screen anti electrostatic interference circuit, the touch-sensitive screen has display module and host system, its characterized in that, the circuit includes:

2. The touch screen antistatic interference circuit of claim 1, wherein the first antistatic module comprises a first electrostatic discharge tube and a second electrostatic discharge tube, a first end of the first electrostatic discharge tube is connected with the voltage input interface, and a second end of the first electrostatic discharge tube is grounded; the first end of the second electrostatic discharge tube is connected with the voltage input interface, and the second end of the second electrostatic discharge tube is grounded;

the second anti-static module comprises a third static electricity discharge pipe and a fourth static electricity discharge pipe; the first end of the third electrostatic discharge tube is respectively connected with the first communication interface and the second communication interface, and the second end of the third electrostatic discharge tube is grounded; and the first end of the fourth electrostatic discharge tube is connected with the first communication interface and the second communication interface, and the second end of the fourth electrostatic discharge tube is grounded.

3. The touch screen anti-electrostatic interference circuit of claim 2, wherein the voltage input interface comprises a power voltage input interface and a driving voltage input interface, and the first anti-electrostatic module is connected to the power voltage input interface and the driving voltage input interface.

4. The touch screen anti-electrostatic interference circuit of claim 3, wherein the first anti-electrostatic module further comprises a first capacitor and a second capacitor,

the first capacitor is connected with the first electrostatic discharge tube in parallel to form a first parallel branch, a first end of the first parallel branch is connected with the power supply voltage input interface, and a second end of the first parallel branch is grounded;

the second capacitor is connected with the second electrostatic discharge tube in parallel to form a second parallel branch, a first end of the second parallel branch is connected with the driving voltage input interface, and a second end of the second parallel branch is grounded.

5. The touch screen anti-static interference circuit of claim 2, wherein the first communication interface comprises a TD0 interface and a TD1 interface; the TD0 interface is connected with a first end of the third electrostatic discharge tube through a first resistor; the TD1 interface is connected with the first end of the fourth electrostatic discharge tube through a second resistor.

6. The touch screen anti-electrostatic interference circuit of claim 5, wherein the second communication interface comprises an IO19 interface and an IO18 interface;

the IO19 interface is connected with the TD0 interface through the first resistor, and the IO19 interface is further connected with a first end of the third electrostatic discharge tube;

the IO18 interface is connected with the TD1 interface through the second resistor, and the IO19 interface is further connected with the first end of the fourth electrostatic discharge tube.

7. The touch screen anti-electrostatic interference circuit of claim 4, further comprising a third capacitor;

a first end of the third capacitor is connected with the driving voltage input interface;

the first end of the third capacitor is also connected with the first end of the second parallel branch;

a second terminal of the third capacitor is connected to ground.

8. The touch screen anti-electrostatic interference circuit of claim 7, wherein the third capacitor is an electrolytic capacitor.

9. A touch screen, characterized in that the touch screen is an OLED display screen, and the touch screen comprises the touch screen anti-electrostatic interference circuit according to any one of claims 1 to 8.

10. A handle, characterized by comprising a housing and the touch screen of claim 9, wherein an accommodating space is provided in the housing, and the touch screen is placed in the accommodating space.