Infrared lamp tube control circuit, touch frame circuit board, infrared touch frame and touch screen

Abstract

The utility model relates to an infrared lamp tube control circuit, a touch frame circuit board, an infrared touch frame and a touch screen, the infrared lamp tube control circuit comprises at least one control chip arranged on each touch frame board card, and the control chip is connected to a main control board; a plurality of pins of the control chip are respectively connected to the switch tube array, and each switch tube of the switch tube array is respectively connected with one infrared lamp tube; the positive electrode end of the infrared lamp tube is connected with an infrared lamp tube working power supply, and the negative electrode end of the infrared lamp tube is connected to a switch tube driving power supply through a switch tube; according to the technical scheme, the phenomenon that the current of the column control circuit is reduced due to voltage drop generated on a power supply and a power line is effectively avoided, and the defect that the current is reduced due to the fact that the voltage drop is increased due to overlong wiring of the power line at the positive electrode end of the infrared lamp tube is overcome.

Description

Technical Field

[0001] This application relates to the field of infrared touch technology, and in particular, to an infrared lamp control circuit, a touch frame circuit board, an infrared touch frame, and a touch screen. Background Art

[0002] In an infrared touch frame, usually multiple groups of infrared pairs are arranged around it. The infrared lamps are distributed on the touch frame boards connected in series. The infrared lamp control circuit of each touch frame board controls the row and column matrix of the infrared lamps through a shift register and a decoder to achieve the control of the transceiver of each infrared lamp, and then processes the infrared light signal such as A / D sampling. The infrared lamps in the row and column are composed of a row-column switch matrix consisting of a logic control line and a switching tube. When the row-column switch is turned on, the current flow direction is that the working power supply of the infrared lamp passes through the infrared lamp to the drive power supply of the switching tube and then to the ground plane. However, under the row-column matrix, each infrared lamp is connected in series with two switching tubes. Since the switching tube itself has resistance, a voltage drop will occur after the voltage passes through the switching tube, ultimately resulting in a decrease in the current flowing through the infrared lamp. Moreover, the power line (TH) of the column matrix has a long trace in the touch frame board, resulting in a large voltage drop, which will also reduce the current flowing through the infrared lamp, affecting the stability of the infrared lamp operation. Summary of the Utility Model

[0003] The purpose of this application is to solve one of the above technical defects, and provide an infrared touch frame circuit board, an infrared touch frame, and an infrared touch screen to reduce the decrease in the current flowing through the infrared lamp, thereby ensuring the stability of the infrared lamp operation.

[0004] An infrared lamp control circuit includes: at least one control chip respectively provided on each touch frame board, and the control chip is connected to the main control board;

[0005] Multiple pins of the control chip are respectively connected to a switching tube array, and each switching tube of the switching tube array is respectively connected to an infrared lamp; wherein, the positive terminal of the infrared lamp is connected to the working power supply of the infrared lamp, and the negative terminal of the infrared lamp is connected to the drive power supply of the switching tube through the switching tube.

[0006] A touch frame circuit board includes: multiple touch frame boards connected in series, and each touch frame board is connected through a connector; wherein, the infrared lamp control circuit is provided on the touch frame board.

[0007] An infrared touch frame includes: a main control board, the touch frame circuit board, and an infrared lamp array provided on each touch frame board.

[0008] An infrared touch screen includes: a display screen and the infrared touch frame; wherein, the infrared touch frame surrounds the display screen.

[0009] In the technical solution of the above embodiment, each infrared lamp tube is only connected in series with one switching tube, which avoids the voltage drop generated on multiple switching tubes, reduces the decrease in the current flowing through the infrared lamp tube, and at the same time, since the power lines of the column matrix are reduced, the current path wiring length is reduced, further reducing the voltage drop on the wiring and ensuring the stability of the operation of the infrared lamp tube.

[0010] Additional aspects and advantages of the present application will be given in part in the following description, and these will become apparent from the following description or be understood through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the following description of the embodiments in conjunction with the drawings, where:

[0012] Figure 1 is a structural diagram of an infrared lamp tube control circuit of the prior art;

[0013] Figure 2 is a structural diagram of the circuit of an exemplary infrared lamp tube;

[0014] Figure 3 is a structural diagram of an infrared lamp tube control circuit of an embodiment;

[0015] Figure 4 is a schematic diagram of the structure of a touch frame board card of an embodiment;

[0016] Figure 5 is a schematic diagram of the structure of a touch frame board card of another embodiment

[0017] Figure 6 is a schematic diagram of the structure of a touch frame circuit board of an exemplary;

[0018] Figure 7 is a schematic diagram of the structure of an exemplary infrared touch frame. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0019] The embodiments of the present application will be described in detail below. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present application and should not be construed as limiting the present application.

[0020] Those skilled in the art can understand that, unless specifically stated otherwise, the singular forms "a", "an", "the", and "said" used herein may also include the plural forms. It should be further understood that the term "comprising" used in the specification of this application means the presence of the stated features, integers, steps, operations, but does not exclude the presence or addition of one or more other features, integers, steps, operations.

[0021] As Figure 1 shown, Figure 1 is the structural diagram of the infrared lamp tube control circuit of the prior art. The infrared lamp tubes of the infrared touch frame board are controlled by a row-column emission matrix. The infrared lamp tubes include infrared receiving tubes and infrared emitting tubes. In the figure, the infrared emitting tubes are taken as an example. The emission matrix is controlled by a shift register and a decoder. The shift register serves as the row control chip. The Q0, Q1... Qn of the shift register are used as the row control signals. Using the serial bus CLK_T (clock signal) and DATA_T (data signal), the decoder serves as the column control chip. The Y0, Y1... Y5 of the decoder are used as the column control signals. Using the parallel wires A0\A1\A2 (address lines) and EN (enable line), when the row control signal is high level and the column control signal is low level, the row-column switch is turned on.

[0022] As Figure 2 shown, Figure 2 is the structural diagram of the circuit of an example infrared lamp tube. The area within the dashed box in the figure is the relevant circuit structure of an infrared lamp tube. As shown in the figure, the row and column logic control lines plus the switching transistors form a row-column switch matrix. When the row-column scan control signal is high level, the switching transistors QH1 and QV1 are turned on. The current of the infrared lamp tube IR1 will pass through the switching transistors QH1 and QV1 in sequence. The current flow direction is from the infrared lamp tube working power supply EVCC through the switching transistor QH1, the infrared lamp tube IR1, the switching transistor QV1, connected to the switching transistor drive power supply PWR and then to the ground plane. A voltage drop will be formed on the switching transistor QH1, resulting in a decrease in current. In addition, the power line of the column matrix has a long wiring. The longer the wiring, the greater the voltage drop, and finally it will also cause a decrease in the current flowing through the infrared lamp tube.

[0023] Referring to Figure 3 shown, Figure 3The following is a structural diagram of an infrared lamp tube control circuit for an embodiment, including: at least one control chip respectively disposed on each touch frame board, each control chip is connected to a main control board, and the main control board controls the infrared scanning of the infrared lamp tube arrays IR1 to IRn on the touch frame board through the control chip, where n represents the number of infrared lamp tubes, and generally n takes a value of dozens; the pins of the control chip (the "○" in the figure represents a pin) are respectively connected to a switch tube array QV1 to QVn, each switch tube QV is connected to one pin, the pin voltage is V, and each switch tube QV is connected to an infrared lamp tube IR; wherein, the positive end of the infrared lamp tube IR is connected to the infrared lamp tube working power supply EVCC, and the negative end is connected to the switch tube driving power supply PWR through the switch tube QV.

[0024] During the control process, the control chip receives the scanning control signal sent by the main control board, and outputs a switch control signal to the switch tube through the corresponding pin to control the target switch tube to conduct, so that the series-connected infrared lamp tube works; for example, the voltage signals output by the pins of the control chip are V0, V1... Vn, and when it is necessary to conduct the connected switch tube, the corresponding output voltage signals V0, V1... Vn are high levels. Exemplarily, for the control chip, it may include a shift register, a 38 decoder or an MCU chip, etc.

[0025] According to the technical solution of the above embodiment, each infrared lamp tube is only connected in series with one switch tube, avoiding voltage drops on multiple switch tubes and reducing the decrease in the current flowing through the infrared lamp tube; as Figure 2 Under the row-column switch matrix shown in the dashed box, the current of the infrared lamp tube IR1 will pass through the switch tube QH1 and the switch tube QV1 successively, and the current flow direction is from the infrared lamp tube working power supply EVCC through the switch tube QH1, the infrared lamp tube IR1, the switch tube QV1 connected to the switch tube driving power supply PWR and then to the ground plane. At this time, two voltage drops will be formed on the switch tube QH1 and the switch tube QV1, and as Figure 3 shown in the dashed box, the infrared lamp tube IR1 is only connected in series with the switch tube QV1, and only one voltage drop is generated on the switch tube QV1. Thus, the decrease in the current flowing through the infrared lamp tube can be reduced; at the same time, since the power line of the column matrix is cancelled, the voltage drop generated on the power line is also avoided, further reducing the voltage drop on the wiring, thereby ensuring the stability of the infrared lamp tube operation.

[0026] For the switch tubes of the switch tube array, generally, a triode can be used. The base of the triode is connected to the main control board, the collector is connected to the negative end of the infrared lamp tube, and the emitter is connected to the switch tube driving power supply PWR. Preferably, the switch tube is a MOS tube; wherein the gate of the MOS tube is connected to the main control board, the drain is connected to the negative end of the infrared lamp tube, and the source is connected to the switch tube driving power supply PWR. Since the on-resistance of the MOS tube is small, the voltage drop can be reduced as much as possible and the flowing current can be increased.

[0027] In one embodiment, as Figure 4 shown, Figure 4 is a schematic diagram of the touch frame board card structure of one embodiment. A main MCU (Microcontroller Unit) may also be provided on the main control board. The main MCU is connected to the control chips on each touch frame board card. Multiple control chips may also be used on the touch frame board card. For example, Figure 4 In it, it is assumed that m control chips are used to provide control for all infrared tubes. Control chips 1 to m respectively control several infrared tubes. During control, the main control board issues a scan control signal to the control chips of the touch frame board card through the main MCU. The control chips convert the scan control signal into a switching control signal for the target infrared tube, which is generally a high-level voltage signal and is output to the switching tube through the corresponding pin to control the switching tube to turn on the infrared tube.

[0028] In one embodiment, as Figure 5 shown, Figure 5 is a schematic diagram of the touch frame board card structure of another embodiment. A slave MCU may also be provided on the touch frame board card. The main MCU is connected to each control chip through the slave MCU on each touch frame board card. During control, the main control board issues a scan control signal to the slave MCU of the touch frame board card through the main MCU, and the slave MCU then converts the scan control signal into a switching control signal for the target infrared tube through each control chip.

[0029] The embodiments of the touch frame circuit board are described below.

[0030] This embodiment provides a touch frame circuit board, as Figure 6 shown, Figure 6 is a schematic diagram of the structure of an example touch frame circuit board, which includes a plurality of serially connected touch frame board cards. Each touch frame board card is connected through a connector to form a touch frame circuit board required for an infrared touch frame around the display screen. Among them, an infrared tube control circuit of any of the foregoing embodiments is provided on each touch frame board card. Further, the touch frame board card includes a transmitting board card and a receiving board card. An infrared tube array is connected to the touch frame board card, including infrared transmitting tubes connected to the transmitting board card and infrared receiving tubes connected to the receiving board card, and the transmitting board card and the receiving board card are connected in an alternating layout.

[0031] According to the technical solution of the above embodiment, through the touch frame board card of the foregoing embodiment, it is possible to effectively avoid the phenomenon that the current decreases due to the voltage drop generated on the power supply and power line of the column control circuit, and avoid the defect that the voltage drop becomes large due to the too long power line of the positive extreme of the infrared tube, resulting in a decrease in current.

[0032] The embodiments of the infrared touch frame and the infrared touch screen are described below.

[0033] The present application provides an infrared touch frame, including the touch frame circuit board of any of the foregoing embodiments; wherein, an infrared lamp tube array is provided on each touch frame board of the touch frame circuit board. As Figure 7 shown, Figure 7 FIG. is a schematic structural diagram of an exemplary infrared touch frame. The infrared touch frame shown in the figure includes touch frame circuit boards ① to ⑧, a total of 8 touch frame circuit boards; preferably, the main control board is integrated on one of the touch frame circuit boards, such as the touch frame circuit board ⑧ shown in the figure.

[0034] The present application provides an infrared touch screen, including: a display screen and the infrared touch frame of any of the foregoing embodiments; wherein the infrared touch frame surrounds the display screen.

[0035] For the infrared touch frame and infrared touch screen of the above embodiments, during operation, the infrared emitting tube and the infrared receiving tube respectively emit and receive infrared light signals, and determine whether there is an object blocking the infrared light signal according to whether the adjusted and stabilized infrared light signal changes, so as to judge the touch operation situation on the display screen and calculate the corresponding touch position coordinates, thereby realizing functions such as clicking, drawing lines, and touching of the infrared touch frame.

[0036] For the infrared touch screen provided in this embodiment, it mainly includes a display screen and an infrared touch frame provided around the display screen. It can be used on various terminal devices. The display screen can be used to display picture content, and at the same time, the infrared touch frame has a touch positioning function, so that the terminal device used can have a touch control function.

[0037] Those skilled in the art of this technology can understand that, unless otherwise defined, all terms (including technical terms and scientific terms) used here have the same meaning as the general understanding of those of ordinary skill in the art in the field to which this application belongs. It should also be understood that terms such as those defined in a general dictionary should be understood to have a meaning consistent with the meaning in the context of the prior art, and will not be interpreted with an idealized or overly formal meaning unless specifically defined as here.

[0038] The above are only some embodiments of the present application. It should be noted that for those of ordinary skill in the art of this technology, without departing from the principle of this application, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of this application.

Claims

1. An infrared lamp tube control circuit, characterized in that, Comprising: At least one control chip respectively disposed on each touch frame board, and the control chip is connected to the main control board; Multiple pins of the control chip are respectively connected to a switch tube array, and each switch tube of the switch tube array is respectively connected to an infrared lamp tube; wherein, the positive electrode of the infrared lamp tube is connected to the infrared lamp tube working power supply, and the negative electrode of the infrared lamp tube is connected to the switch tube drive power supply through the switch tube.

2. The infrared lamp tube control circuit according to claim 1, characterized in that, The switch tube is a triode; wherein, the base of the triode is connected to the main control board, the collector is connected to the negative electrode of the infrared lamp tube, and the emitter is connected to the switch tube drive power supply.

3. The infrared lamp tube control circuit according to claim 1, wherein The switch tube is a MOS tube; wherein, the gate of the MOS tube is connected to the main control board, the drain is connected to the negative electrode of the infrared lamp tube, and the source is connected to the switch tube drive power supply.

4. The infrared lamp tube control circuit according to claim 1, characterized in that, The control chip includes: a shift register, a 38 decoder or an MCU chip.

5. The infrared lamp tube control circuit according to claim 1, characterized in that, A main MCU is provided on the main control board, and the main MCU is connected to the control chips on each touch frame board.

6. The infrared lamp tube control circuit according to claim 5, wherein, A slave MCU is further provided on the touch frame board, and the main MCU is connected to the control chip through the slave MCUs on each touch frame board.

7. A touch frame circuit board, characterized in that Comprising: Multiple serially-connected touch frame boards, and each of the touch frame boards is connected through a connector; wherein, the touch frame board is provided with the infrared lamp tube control circuit according to any one of claims 1-6.

8. The touch frame circuit board according to claim 7, wherein The touch frame board includes a transmitting board and a receiving board; the infrared lamp tube includes an infrared transmitting tube connected to the transmitting board and an infrared receiving tube connected to the receiving board.

9. An infrared touch frame, characterized in that, Comprising: A main control board, the touch frame circuit board according to claim 7 or 8, and an infrared lamp tube array disposed on each touch frame board.

10. An infrared touch screen, characterized in that, Comprising: A display screen and the infrared touch frame according to claim 9; wherein, the infrared touch frame surrounds the display screen.

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