WO2018205834A1

WO2018205834A1 - Touch control screen drive circuit, touch control screen and electronic device

Info

Publication number: WO2018205834A1
Application number: PCT/CN2018/084419
Authority: WO
Inventors: 杨怀; 伏奎; 陈再成
Original assignee: Oppo广东移动通信有限公司
Priority date: 2017-05-09
Filing date: 2018-04-25
Publication date: 2018-11-15
Also published as: CN107037930A; CN107037930B

Abstract

Provided is a touch control screen drive circuit. The touch control screen drive circuit comprises a charge pump, a current limiting unit and a switching unit, wherein the switching unit is connected to a power supply voltage and is used for connecting the charge pump when an amplitude value of a signal received by an antenna module is greater than a first pre-set voltage, and is used for connecting the current limiting unit when an amplitude value of a signal received by the antenna module is less than the first pre-set voltage so as to supply power for a touch control module via the current limiting unit.

Description

Touch screen driving circuit, touch screen and electronic device

The present application claims priority to Chinese Patent Application No. 200910322123.0, entitled "Touch Screen Drive Circuit and Electronic Device", filed on May 09, 2017, the entire contents of which is incorporated herein by reference. in.

Technical field

The present invention relates to the field of terminal technologies, and in particular, to a touch screen driving circuit, a touch screen, and an electronic device.

Background technique

After receiving the signal sent by the base station through the antenna module, the intelligent terminal will report the amplitude value of a signal to the base station. The return value is in one-to-one correspondence with the signal strength of the base station received by the intelligent terminal. If there is interference in the intelligent terminal, and the signal strength transmitted by the base station to the terminal remains unchanged, the signal received by the intelligent terminal is weakened due to the interference signal, and the amplitude value of the signal returned by the terminal to the base station may change. In the case that the intelligent terminal is interfered and the actual received signal strength is weak, such a problem occurs: the first is that the signal is too weak, and the received signal cannot be demodulated to cause the communication to be invalid. The second is that the signal strength reported by the terminal to the base station is lower than the actual arrival strength, which causes the base station to continue to increase the transmission power so that the signal strength of the terminal reaches the terminal requirement, which causes waste of resources.

technical problem

In the related art, the interference of the touch screen to the radio frequency communication mainly relates to the switching process of the charge pump. The use of a charge pump will increase the interference to the received signal of the antenna module, resulting in a weakened received signal.

Technical solution

The embodiment of the invention provides a touch screen driving circuit, a touch screen and an electronic device, which have the beneficial effects of reducing the interference of the touch module on the signal received by the antenna module.

The embodiment of the invention provides a touch screen driving circuit, which is used in an electronic device, the electronic device has an antenna module and a touch module, and the touch screen driving circuit comprises a charge pump, a current limiting unit and a switching unit;

The switching unit is connected to the power supply voltage, and the switching unit is configured to communicate with the charge pump when the amplitude value of the signal received by the antenna module is greater than the first preset voltage, so that the charge pump boosts the power supply voltage and provides the touch mode And communicating with the current limiting unit through the current limiting unit when the amplitude value of the signal received by the antenna module is less than the first preset voltage;

The embodiment of the invention further provides a touch screen, comprising a touch module and a touch screen driving circuit, wherein the touch screen driving circuit comprises a charge pump, a current limiting unit and a switching unit;

The switching unit is connected to the power supply voltage, and the switching unit is configured to communicate with the charge pump when the amplitude value of the signal received by the antenna module of the electronic device is greater than the first preset voltage, so that the charge pump will supply power The voltage is boosted and supplied to the touch module; and is configured to communicate with the current limiting unit when the amplitude value of the signal received by the antenna module is less than the first preset voltage to pass the The current limiting unit supplies power to the touch module.

An embodiment of the present invention further provides an electronic device, including the above touch screen driving circuit.

Beneficial effect

When the touch screen driving circuit provided by the embodiment of the present invention detects that the signal strength received by the antenna module is lower than the first preset voltage, the driving voltage is directly transmitted to the touch through the current limiting unit without being boosted by the charge pump. The module reduces the interference of the touch module on the signal received by the antenna module.

DRAWINGS

1 is a first schematic structural view of an electronic device in an embodiment of the present invention.

2 is a schematic view showing a second structure of an electronic device in an embodiment of the present invention.

3 is a schematic view showing a third structure of an electronic device in an embodiment of the present invention.

4 is a first schematic structural diagram of a touch screen driving circuit of an electronic device according to an embodiment of the present invention.

FIG. 5 is a second schematic structural diagram of a touch screen driving circuit of an electronic device according to an embodiment of the present invention.

FIG. 6 is a third schematic structural diagram of a touch screen driving circuit of an electronic device according to an embodiment of the present invention.

Embodiments of the invention

The embodiments of the present invention are described in detail below, and the examples of the embodiments are illustrated in the drawings, wherein the same or similar reference numerals indicate the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the drawings are intended to be illustrative of the invention and are not to be construed as limiting.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", " Orientations of "post", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc. The positional relationship is based on the orientation or positional relationship shown in the drawings, and is merely for the convenience of the description of the present invention and the simplified description, and is not intended to indicate or imply that the device or component referred to has a specific orientation, and is constructed and operated in a specific orientation. Therefore, it should not be construed as limiting the invention. Moreover, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, features defining "first" or "second" may include one or more of the described features either explicitly or implicitly. In the description of the present invention, the meaning of "a plurality" is two or more unless specifically and specifically defined otherwise.

In the description of the present invention, it should be noted that the terms "installation", "connected", and "connected" are to be understood broadly, and may be fixed or detachable, for example, unless otherwise explicitly defined and defined. Connected, or integrally connected; may be mechanically connected, may be electrically connected or may communicate with each other; may be directly connected, or may be indirectly connected through an intermediate medium, may be internal communication of two elements or interaction of two elements relationship. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood on a case-by-case basis.

In the present invention, the first feature "on" or "under" the second feature may include direct contact of the first and second features, and may also include first and second features, unless otherwise specifically defined and defined. It is not in direct contact but through additional features between them. Moreover, the first feature "above", "above" and "above" the second feature includes the first feature directly above and above the second feature, or merely indicating that the first feature level is higher than the second feature. The first feature "below", "below" and "below" the second feature includes the first feature directly below and below the second feature, or merely the first feature level being less than the second feature.

The following disclosure provides many different embodiments or examples for implementing different structures of the present invention. In order to simplify the disclosure of the present invention, the components and arrangements of the specific examples are described below. Of course, they are merely examples and are not intended to limit the invention. In addition, the present invention may be repeated with reference to the numerals and/or reference numerals in the various examples, which are for the purpose of simplicity and clarity, and do not indicate the relationship between the various embodiments and/or arrangements discussed. Moreover, the present invention provides examples of various specific processes and materials, but one of ordinary skill in the art will recognize the use of other processes and/or the use of other materials.

Embodiments of the present invention provide an electronic device. The electronic device can be a device such as a smartphone or a tablet. Referring to FIG. 1 and FIG. 2 , the electronic device 1 includes a cover 101 , a display screen 102 , a circuit board 103 , a power module 104 , a housing 105 , and a touch module 106 .

The touch module 106 covers the display screen 102. The cover 101 is mounted on the touch module 106 to cover the touch module 106. The cover plate 101 may be a transparent glass cover. In some embodiments, the cover plate 101 can be a glass cover plate made of a material such as sapphire.

The display screen 102 is mounted on the housing 105 to form a display surface of the electronic device 100. The display screen 102 can include a display area 102A and a non-display area 102B. The display area 102A is for displaying information such as images, texts, and the like. The non-display area 102B does not display information. The bottom of the non-display area 102B may be provided with functional components such as a fingerprint module and a touch circuit.

The circuit board 103 is mounted inside the housing 105. The circuit board 103 can be a motherboard of the electronic device 100. Functional components such as a camera, a proximity sensor, and a processor can be integrated on the circuit board 103. At the same time, the display screen 102 can be electrically connected to the circuit board 103.

In some embodiments, a circuit board 103 is provided with a radio frequency (RF) circuit. The radio frequency circuit can communicate with a network device (eg, a server, a base station, etc.) or other electronic device (eg, a smart phone, etc.) through a wireless network to complete transceiving information with the network device or other electronic device.

Please refer to FIG. 3 at the same time. FIG. 3 is a schematic structural diagram of an electronic device according to an embodiment of the present invention. The electronic device further includes a touch screen driving circuit 107, an antenna module 108, and a power module 104. The touch panel driving circuit 107 is electrically connected to the antenna module 108, the touch module 106, and the power module 104, respectively.

The antenna module 108 is configured to receive a wireless signal sent by an external electronic device and send a wireless signal to the external electronic device.

The touch module 106 includes a touch substrate and a touch sensing circuit disposed on the touch substrate. When the touch module 106 is applied to a mobile terminal such as a mobile phone, it covers the display screen 102 of the mobile terminal.

The power module 104 is configured to supply power to each power module of the electronic device.

The touch screen driving circuit 107 uses the power supply voltage provided by the power module 104 to supply power to the touch module 106, so that the touch module 106 generates a touch sensing electric field to sense the user's touch on the touch module 106. operating.

In some embodiments, the touch screen driving circuit 107 includes a first comparison unit 10, a switching unit 20, a charge pump 30, and a current limiting unit 40. The comparison voltage terminal of the first comparison unit 10 is connected to the antenna module 108 to detect the strength of the wireless signal received by the antenna module 108. The reference voltage terminal of the first comparison unit 10 is connected to the first preset voltage V0 as a reference voltage. The output end of the first comparison unit 10 is connected to the control end of the switching unit 20, the first output end of the switching unit 20 is connected to the charge pump 30, and the second output end of the switching unit 20 and the current limiting unit 40 The charge pump 30 and the current limiting unit 40 are respectively connected to the touch module 106.

The first comparison unit 10 can be a comparison circuit, such as a common comparison circuit composed of an operational amplifier. It outputs a control signal to the switching unit 20 based on the comparison result.

The switching unit 20 can be an input and output output gating circuit that selectively communicates with the charge pump 30 or the current limiting unit 40 in accordance with a control signal.

In some embodiments, as shown in FIG. 4, the switching unit 20 may include a first transistor Q1, a second transistor Q2, and an inverter circuit 21. An input end of the inverter circuit 21 is connected to an output end of the first comparison unit 10, an output end of the inverter circuit 21 is connected to a control end of the second transistor Q2, and an output of the second transistor Q2 is output. The end is connected to the current limiting unit 40. The control terminal of the first transistor Q1 is connected to the output terminal of the first comparison unit 10, and the output terminal of the first transistor Q1 is connected to the charge pump 30. The input terminals of the first transistor Q1 and the second transistor Q2 are connected and serve as an input terminal of the switching unit 20, which is connected to the power supply voltage VCC. In this embodiment, the power supply voltage VCC is provided by the power module 104. The first transistor Q1 and the second transistor Q2 are field effect transistors, and of course, they may be crystal transistors. The switching characteristics of the first transistor Q1 and the second transistor Q2 are the same, and both are turned on when the control terminal is at a high level or when it is at a low level. The first transistor Q1 and the second transistor Q2 may both be NMOS field effect transistors.

The inverter circuit 21 can be a CMOS inverter circuit for inverting a voltage signal outputted by the output end of the first comparison unit 10, for example, a low level becomes a high level, and a high level becomes a low level. Therefore, the switching condition of the first transistor Q1 and the second transistor Q2 is opposite.

The current limiting unit 40 can be a current limiting resistor R1. It can be understood that the current limiting unit 40 can also adopt a constant current diode. Therefore, excessive current is directly prevented from flowing into the touch sensing circuit of the touch module 106.

In other embodiments, as shown in FIG. 5, the switching unit 20 may include a third transistor Q3 and a fourth transistor Q4, and the output ends of the first comparing unit 10 and the third transistor Q3 are respectively controlled. The terminal and the control terminal of the fourth transistor Q4 are connected. The input end of the third transistor Q3 and the input end of the fourth transistor Q4 are respectively connected to the power supply voltage VCC. The output of the third transistor Q3 is connected to the charge pump 30. The output end of the fourth transistor Q4 is connected to the current limiting unit 40. The switching characteristics of the third transistor Q3 and the fourth transistor Q4 are opposite, such that when the third transistor Q3 and the fourth transistor Q4 receive the control signal output by the first comparison unit 10, the switching states are reversed. among them. The third transistor can be an NMOS transistor, and the fourth transistor can be a PMOS transistor.

When the electronic device is in operation, the antenna module 108 receives the wireless signal sent by the external device, and the first comparing unit 10 compares the amplitude value of the wireless signal received by the antenna module 108 with the first predetermined voltage. When the amplitude value is smaller than the first preset voltage, the interference generated by the touch module 106 and the charge pump 80 is relatively serious, so the switching unit 20 is disconnected from the charge pump 30 and connected to the current limiting unit 40, and the power is turned on. The power supply voltage provided by the module 104 is provided to the touch module 106 through the current limiting unit, thereby preventing the charge pump 30 from boosting the interference to the antenna module 108. When the amplitude value is greater than the first preset voltage, the touch module 106 and the charge pump 30 have weak or no interference to the antenna module 108. Therefore, the charge pump 30, the switching unit 20 and the charge pump 30 are normally used. Connected and disconnected from the current limiting unit 40.

It can be seen that the touch screen driving circuit provided by the embodiment of the present invention directly passes the driving voltage without being boosted by the charge pump when detecting that the amplitude value of the signal received by the antenna module is lower than the first preset voltage value. The current limiting unit is transmitted to the touch module, thereby reducing interference of the touch module with the signal received by the antenna module.

Referring to FIG. 6 , in other embodiments, the touch screen driving circuit 107 may include a first comparison unit 10 , a switching unit 20 , a charge pump 30 , a current limiting unit 40 , a first switching unit 50 , and a second comparison unit . 60. The second switch unit 70.

The comparison voltage terminal of the first comparison unit 10 is connected to the antenna module 108 to detect the strength of the wireless signal received by the antenna module 108. The reference voltage terminal of the first comparison unit 10 is connected to the first preset voltage as a reference voltage. The output of the first comparison unit 10 is connected to the control terminal of the switching unit 20. The first output of the switching unit 20 is connected to the charge pump 30, and the second output of the switching unit 20 is connected to the current limiting unit 40. The charge pump 30 and the current limiting unit 40 are respectively connected to the touch module 106.

The control end of the first switching unit 50 is connected to the switching unit 20 and the common node of the charge pump 30. The input end of the first switching unit 50 is connected to the antenna module 108 to detect the signal amplitude value received by the antenna module 108. The output of the first switching unit 50 is connected to the comparison terminal of the second comparison unit 60. The reference voltage terminal of the second comparison unit 60 is connected to the second preset voltage. The output end of the second comparison unit 60 is connected to the control end of the second switch unit 70, and the charge pump 30 is connected to the touch module 106 via the second switch unit 70.

When the switching unit 20 is connected to the charge pump 30, the first switching unit 50 is turned on, and the second comparing unit 60 compares the signal amplitude value received by the antenna module 108 with the second preset voltage V1. When the signal amplitude value is greater than the second preset voltage, the second comparison unit outputs an on signal to the second switching unit 70 such that the second switching unit 70 is turned on. When the signal amplitude value is less than the second preset voltage, the second comparison unit 60 outputs an off signal to the second switching unit 70, so that the second switching unit 70 is turned off. The second preset voltage V1 may be equal to the first preset voltage V0 or may be smaller than the first preset voltage V0.

The first switch unit 50 and the second switch unit 70 can each be a triode, such as a field effect transistor or a crystal triode. The second comparison unit 60 can be a comparison circuit, such as a common comparison circuit formed by an operational amplifier. It outputs a control signal to the second switching unit 20 based on the comparison result.

When the electronic device is in operation, the antenna module 108 receives the wireless signal sent by the external device, and the first comparing unit 10 compares the amplitude value of the wireless signal received by the antenna module 108 with the first preset voltage, when the amplitude value is less than the first When the voltage is preset, the interference generated by the touch module 106 and the charge pump 80 is relatively serious. Therefore, the switching unit 20 is disconnected from the charge pump 30 and connected to the current limiting unit 40, and the power supply provided by the power module 104 is provided. The voltage is supplied to the touch module 106 through the current limiting unit, thereby preventing the charge pump 30 from boosting the interference to the antenna module 108. When the amplitude value is greater than the first preset voltage, the touch module 106 and the charge pump 30 have weak or no interference to the antenna module 108. Therefore, the charge pump 30, the switching unit 20 and the charge pump 30 are normally used. Connected and disconnected from the current limiting unit 40.

Further, by detecting the signal strength received by the antenna module 108 without using the charge pump 30, when the charge pump 30 is not used, if the touch module 106 still interferes with the antenna module 108, then The driving voltage may not be provided to the touch module 106, thereby completely eliminating interference to the antenna module 300.

The embodiment further provides a touch screen, which can be applied to an electronic device. The touch screen can include a touch module and a touch screen driving circuit. The touch module can include a touch substrate and a touch sensing circuit disposed on the touch substrate. The touch screen driving circuit can supply power to the touch module by using a power supply voltage provided by the power module of the electronic device, so that the touch module generates a touch sensing electric field to sense a touch operation of the touch module by the user. .

The touch screen driving circuit may include a charge pump, a current limiting unit, and a switching unit. The switching unit is connected to the power supply voltage, and the switching unit is configured to communicate with the charge pump when the amplitude value of the signal received by the antenna module of the electronic device is greater than the first preset voltage, so that the charge pump boosts the power supply voltage Provided to the touch module; and configured to communicate with the current limiting unit when the amplitude of the signal received by the antenna module is less than the first predetermined voltage, to pass the current limiting unit to the touch module powered by.

In an embodiment, the current limiting unit may be a current limiting resistor or a constant current diode.

In an embodiment, the touch screen driving circuit further includes a first comparing unit, the first comparing unit is connected to the antenna module, and the amplitude value of the signal received by the antenna module is compared with the first preset. The voltages are compared and the comparison result is sent to the switching unit.

In an embodiment, the first comparison unit may be a comparison circuit composed of an operational amplifier.

In an embodiment, the switching unit may be a gate circuit that inputs two outputs, and the switching unit selectively communicates with the charge pump or the current limiting unit according to the control signal.

In one embodiment, the switching unit includes an inverter circuit, a first transistor, and a second transistor, and an output of the first comparison unit is coupled to an input of the inverter circuit, and an output of the inverter circuit The end is connected to the control end of the second transistor, and the output end of the first comparison unit is connected to the control end of the first transistor. An input end of the first triode and an input end of the second triode are respectively connected to a supply voltage, and an output end of the first triode is connected to the charge pump, and an output end of the second triode is The current limiting unit is connected, and the switching characteristics of the first triode and the second triode are the same.

In one embodiment, the first transistor and the second transistor may both be NMOS transistors.

In another embodiment, the first triode and the second triode may also be crystalline triodes.

In one embodiment, the inverting circuit can be a CMOS inverting circuit.

In another embodiment, the switching unit includes a third triode and a fourth triode, and the output ends of the first comparison unit and the control end of the third triode and the control of the fourth triode End connection. An input end of the third triode and an input end of the fourth triode are respectively connected to a power supply voltage, and an output end of the third triode is connected to the charge pump, and an output end of the fourth triode is The current limiting unit is connected, and the third triode has opposite switching characteristics to the fourth triode.

In one embodiment, the third transistor can be an NMOS transistor and the fourth transistor can be a PMOS transistor.

In an embodiment, the touch screen driving circuit may further include a second comparison unit, a first switching unit, and a second switching unit.

The first switch unit is connected to the switching unit and the common node of the charge pump, and the first switch unit is connected to the antenna module to detect an amplitude value of a signal received by the antenna module, the first switch unit, The second comparison unit and the second switch unit are sequentially connected, and the charge pump is connected to the touch module through the second switch unit.

When the switching unit is connected to the charge pump, the first switching unit is turned on, and when the amplitude value of the signal is greater than the second preset voltage, the second comparing unit outputs a conduction signal to the second switching unit such that the second switching unit leads When the amplitude value of the signal is less than the second preset voltage, the second comparing unit outputs the cutoff signal to the second switching unit, so that the second switching unit is turned off.

In an embodiment, the second preset voltage may be less than or equal to the first preset voltage.

The embodiment further provides an electronic device, which may include the touch screen driving circuit provided by the embodiment.

In the description of the present specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiment", "example", "specific example", or "some examples", etc. The specific features, structures, materials or characteristics described in the embodiments or examples are included in at least one embodiment or example of the invention. In the present specification, the schematic representation of the above terms does not necessarily mean the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples.

In the above, the present invention has been disclosed in the above preferred embodiments, but the preferred embodiments are not intended to limit the present invention, and those skilled in the art can make various modifications without departing from the spirit and scope of the invention. The invention is modified and retouched, and the scope of the invention is defined by the scope defined by the claims.

Claims

A touch screen driving circuit is used in an electronic device, wherein the electronic device has an antenna module and a touch module, wherein the touch screen driving circuit includes a charge pump, a current limiting unit, and a switching unit;

The switching unit is connected to the power supply voltage, and the switching unit is configured to communicate with the charge pump when the amplitude value of the signal received by the antenna module is greater than the first preset voltage, so that the charge pump supplies the voltage Providing to the touch module after boosting; and communicating with the current limiting unit when the amplitude value of the signal received by the antenna module is smaller than the first preset voltage to pass the limit The flow unit supplies power to the touch module.
The touch screen driving circuit of claim 1 , wherein the touch screen driving circuit further comprises a first comparing unit, wherein the first comparing unit is connected to the antenna module to connect the antenna module The amplitude value of the received signal is compared with the first predetermined voltage, and the comparison result is sent to the switching unit.
The touch screen driving circuit according to claim 2, wherein the switching unit comprises an inverter circuit, a first transistor, and a second transistor, and an output end of the first comparison unit and the inversion An input end of the circuit is connected, an output end of the inverter circuit is connected to a control end of the second transistor, and an output end of the first comparison unit is connected to a control end of the first transistor;

An input end of the first triode and an input end of the second triode are respectively connected to a power supply voltage, and an output end of the first triode is connected to the charge pump, the second three pole The output end of the tube is connected to the current limiting unit, and the switching characteristics of the first triode and the second triode are the same.
The touch screen driving circuit of claim 3, wherein the first transistor and the second transistor are both NMOS transistors.
The touch screen driving circuit according to claim 2, wherein the switching unit comprises a third transistor and a fourth transistor, and an output end of the first comparison unit and the third transistor respectively a control terminal and a control terminal of the fourth transistor;

An input end of the third triode and an input end of the fourth triode are respectively connected to a supply voltage, and an output end of the third triode is connected to the charge pump, the fourth three pole The output end of the tube is connected to the current limiting unit, and the third triode has opposite switching characteristics to the fourth triode.
The touch screen driving circuit of claim 5, wherein the third transistor is an NMOS transistor, and the fourth transistor is a PMOS transistor.
The touch screen driving circuit of claim 1 , wherein the current limiting unit is a current limiting resistor.
The touch screen driving circuit according to claim 1, wherein the current limiting unit is a constant current diode.
The touch screen driving circuit of claim 1 , wherein the touch screen driving circuit further comprises a second comparing unit, a first switching unit, and a second switching unit;

The first switch unit is connected to the switching unit and the common node of the charge pump, and the first switch unit is connected to the antenna module to detect an amplitude value of a signal received by the antenna module. The first switch unit, the second comparison unit, and the second switch unit are sequentially connected, and the charge pump is connected to the touch module through the second switch unit;

The first switching unit is turned on when the switching unit is connected to the charge pump, and when the amplitude value of the signal is greater than the second preset voltage, the second comparing unit outputs a conduction signal to the second switching unit to make The second switching unit is turned on; when the amplitude value of the signal is less than the second preset voltage, the second comparing unit outputs an off signal to the second switching unit, so that the second switching unit is turned off.
The touch screen driving circuit according to claim 3, wherein the inverter circuit is a CMOS inverter circuit.
The touch screen driving circuit according to claim 2, wherein said first comparing unit is a comparing circuit composed of an operational amplifier.
The touch screen driving circuit according to claim 1, wherein the switching unit is a gate circuit for inputting and outputting, and the switching unit is selectively coupled to the charge pump or the current limiting unit according to a control signal. Connected.
The touch screen driving circuit of claim 3, wherein the first transistor and the second transistor are all transistors.
The touch screen driving circuit of claim 9, wherein the second preset voltage is smaller than the first preset voltage.
A touch screen includes a touch module and a touch screen driving circuit, and the touch screen driving circuit includes a charge pump, a current limiting unit, and a switching unit;

The switching unit is connected to the power supply voltage, and the switching unit is configured to communicate with the charge pump when the amplitude value of the signal received by the antenna module of the electronic device is greater than the first preset voltage, so that the charge pump will supply power The voltage is boosted and supplied to the touch module; and is configured to communicate with the current limiting unit when the amplitude value of the signal received by the antenna module is less than the first preset voltage to pass the The current limiting unit supplies power to the touch module.
The touch screen driving circuit of claim 15 , wherein the touch screen driving circuit further comprises a first comparing unit, wherein the first comparing unit is connected to the antenna module to receive the antenna module The amplitude value of the signal is compared with the first predetermined voltage, and the comparison result is sent to the switching unit.
The touch screen of claim 16, wherein the switching unit comprises an inverter circuit, a first transistor, and a second transistor, an output of the first comparison unit and the inverter circuit The input end is connected, the output end of the inverter circuit is connected to the control end of the second transistor, and the output end of the first comparison unit is connected to the control end of the first transistor;

An input end of the first triode and an input end of the second triode are respectively connected to a power supply voltage, and an output end of the first triode is connected to the charge pump, the second three pole The output end of the tube is connected to the current limiting unit, and the switching characteristics of the first triode and the second triode are the same.
The touch screen of claim 17, wherein the first transistor and the second transistor are both NMOS transistors.
The touch screen according to claim 16, wherein the switching unit comprises a third transistor and a fourth transistor, and the output ends of the first comparing unit and the third transistor are respectively controlled And connecting the control ends of the fourth triode;

An input end of the third triode and an input end of the fourth triode are respectively connected to a supply voltage, and an output end of the third triode is connected to the charge pump, the fourth three pole The output end of the tube is connected to the current limiting unit, and the third triode has opposite switching characteristics to the fourth triode.
An electronic device comprising the touch screen driving circuit of any one of claims 1-14.