Display screen detection circuit providing VCC and VDD double voltages

Abstract

The utility model discloses a display screen detection circuit providing VCC and VDD double voltages, which comprises a boost module and a control switch module, the boost module comprises a boost chip, a boost output terminal and a boost input terminal, the boost output terminal is coupled with a VCC terminal, and the boost input terminal is coupled with the VCC terminal. The boost input terminal is coupled with the control switch module, and the control switch module comprises a switch tube. The display screen detection circuit for providing VCC and VDD double voltages controls signals through an MOS tube. When the MOS tube is turned on, the boost module has an input voltage, the VCC is boosted normally, and the display module is connected with the VCC voltage. When the MOS tube is closed, the boost module has no input voltage, the VCC cannot be boosted, and the VCC voltage is cut off by the display module. Thus, the working state is controlled through the MOS tube, the power-on and power-off sequence of the VDD and the VCC can be controlled through a circuit and a signal, and fool-proof, good reliability, convenient operation and high practicability are achieved.

Description

Technical Field

[0001] The utility model relates to a display screen detection circuit, more specifically, to a display screen detection circuit which provides a dual voltage of VCC and VDD. Background Art

[0002] Usually, PMOLED and STN displays require at least two voltages to drive the display screen, of which the following two are necessary: ​​VDD and VCC. VDD is used to drive the display driver IC, which is usually 3.3V or 3.0V. VCC is used to drive the glass display, PMOLED displays are used to drive OLED, and STN displays are used to drive liquid crystal flipping. The VCC voltage is usually above 10V or close to 10V.

[0003] The power-on and power-off sequences of the above two voltages are controlled. When powering on, first turn on the low voltage, then the high voltage. When powering off, first turn off the high voltage, then the low voltage. For the control of this sequence, the current testing method is to control the power-on and power-off sequence by manually controlling the power switch. During the test process, negligence or carelessness may cause the power-on and power-off sequence to be wrong, resulting in problems that cannot be prevented.

[0004] Chinese invention patent document CN111681617A discloses a dual display screen backlight driving circuit applied to a dual display screen device including a left backlight circuit for providing backlight for a left display screen and a right backlight circuit for providing backlight for a right display screen, comprising: a boost circuit respectively connected to the left backlight circuit and the right backlight circuit; a combined backlight modulation circuit respectively connected to the left backlight circuit and the right backlight circuit; a controller respectively connected to the boost circuit and the combined backlight modulation circuit, for controlling the boost circuit to perform a boost operation on its own input voltage after receiving a screen backlight turn-on instruction to provide a conduction voltage for the left backlight circuit and the right backlight circuit, and controlling the combined backlight modulation circuit to alternately connect the working branches of the left backlight circuit and the right backlight circuit so that the left backlight circuit and the right backlight circuit work alternately. The controller is connected to the display screen module of the dual display screen device; and the controller is specifically used to notify the display screen module to output the first PWM signal and the second PWM signal with the same waveform after receiving the screen backlight start instruction; control the first backlight circuit to work at a certain frequency according to the received first PWM signal, and delay the control of the second backlight circuit to work at a certain frequency according to the received second PWM signal, so that the two backlight circuits work alternately; wherein, the second backlight circuit delays the start time of the first backlight circuit < the working cycle of the first backlight circuit and the second backlight circuit < the visual persistence effect time; the first backlight circuit is the left backlight circuit or the right backlight circuit, and correspondingly, the second backlight circuit is the right backlight circuit or the left backlight circuit. The combined backlight modulation circuit includes a first switch tube, a second switch tube, a first resistor and a second resistor; wherein: the first end of the first switch tube is connected to the negative end of the power supply of the left backlight circuit, the second end of the first switch tube is connected to the first end of the first resistor, the second end of the first resistor is grounded, the first end of the second switch tube is connected to the negative end of the power supply of the right backlight circuit, the second end of the second switch tube is connected to the first end of the second resistor, the second end of the second resistor is grounded, and the control end of the first switch tube and the control end of the second switch tube are both connected to the controller; accordingly, the controller is specifically used to control the working branches of the left backlight circuit and the right backlight circuit to be alternately connected by controlling the on-off state of the first switch tube and the second switch tube, so that the left backlight circuit and the right backlight circuit work alternately. The combined backlight modulation circuit also includes: a first pull-down resistor with a first end connected to the control end of the first switch tube and a second end grounded; a second pull-down resistor with a first end connected to the control end of the second switch tube and a second end grounded.Obviously, after receiving the screen backlight on command, the controller of the patent controls the boost circuit to boost its own input voltage to provide a conduction voltage for the left backlight circuit and the right backlight circuit, and controls the combined backlight modulation circuit to alternately connect the working branches of the left backlight circuit and the right backlight circuit, so that the left backlight circuit and the right backlight circuit work alternately. However, this structure cannot solve the problem of the existing two-way voltage. Utility Model Content

[0005] Based on this, it is necessary to provide a display screen detection circuit that provides dual voltages of VCC and VDD for the above technical problems. The display screen detection circuit that provides dual voltages of VCC and VDD includes a boost module and a control switch module. The boost module includes a boost chip, a boost output terminal and a boost input terminal. The boost output terminal is coupled to the VCC terminal, and the boost input terminal is coupled to the control switch module. The control switch module includes a switch tube. The display screen detection circuit that provides dual voltages of VCC and VDD controls the signal through a MOS tube. When the MOS tube is turned on, the boost module has an input voltage, the VCC is boosted normally, and the display module is connected to the VCC voltage. When the MOS tube is turned off, the boost module has no input voltage, cannot boost VCC, and the display module disconnects the VCC voltage. In this way, by controlling the working state through the MOS tube, the power-on and power-off sequence of VDD and VCC can be controlled by circuits and signals, so that it can be foolproof, has good reliability, is easy to operate, and has strong practicality.

[0006] In order to solve the above technical problems, the utility model adopts the following technical solutions:

[0007] A display screen detection circuit that provides dual voltages of VCC and VDD, characterized in that the display screen detection circuit that provides dual voltages of VCC and VDD comprises a boost module and a control switch module, the boost module comprises a boost chip, a boost output terminal and a boost input terminal, the boost output terminal is coupled to the VCC terminal, the boost input terminal is coupled to the control switch module, and the control switch module comprises a switch tube.

[0008] As a preferred implementation of the display screen detection circuit providing dual voltages of VCC and VDD provided by the utility model, the switch tube is a MOS tube, the drain of the MOS tube is coupled to the boost input terminal, the source of the MOS tube is coupled to the VDD terminal, and the gate of the MOS tube is coupled to the enable control terminal VCC_EN terminal.

[0009] As a preferred implementation of the display screen detection circuit providing dual voltages of VCC and VDD provided by the utility model, the switch tube is a triode.

[0010] As a preferred implementation of the display screen detection circuit providing VCC and VDD dual voltages provided by the utility model,

[0011] The model of the boost chip is AP3015KTR-G1.

[0012] As a preferred implementation of the display screen detection circuit providing dual voltages of VCC and VDD provided by the utility model, a coupling capacitor C7 is provided between the boost output terminal and the ground line.

[0013] As a preferred implementation of the display screen detection circuit providing dual voltages of VCC and VDD provided by the utility model, a coupling capacitor C6 is provided between the boost input terminal and the ground line.

[0014] As a preferred implementation of the display screen detection circuit providing dual voltages of VCC and VDD provided by the utility model, the SW pin of the boost chip is coupled to the VCC terminal via a diode D1.

[0015] As a preferred implementation of the display screen detection circuit providing dual voltages of VCC and VDD provided by the utility model, an inductor L1 is provided between the SW pin and the VIN pin of the boost chip.

[0016] As a preferred implementation of the display screen detection circuit providing dual voltages of VCC and VDD provided by the utility model, the voltage of the VDD terminal is 3.3V.

[0017] As a preferred implementation of the display screen detection circuit providing dual voltages of VCC and VDD provided by the utility model, the voltage of the VDD terminal is 3.0V.

[0018] Compared with the prior art, the utility model has the following beneficial effects:

[0019] The utility model provides a display screen detection circuit that provides dual voltages of VCC and VDD. The display screen detection circuit that provides dual voltages of VCC and VDD controls signals through MOS tubes. When the MOS tube is turned on, the boost module has input voltage, boosts VCC normally, and the display module is connected to the VCC voltage. When the MOS tube is turned off, the boost module has no input voltage, cannot boost VCC, and the display module disconnects the VCC voltage. In this way, by controlling the working state through the MOS tube, the power-on and power-off sequence of VDD and VCC can be controlled by circuits and signals, so as to be foolproof, reliable, easy to operate, and highly practical.

[0020] In addition, the SW pin of the boost chip can be coupled to the VCC terminal via a diode D1. An inductor L1 is provided between the SW pin of the boost chip and the VIN pin. The diode D1 can effectively prevent abnormal current backflow at the VCC terminal and protect the safety of the circuit.

[0021] In addition, the switch tube can be a triode, which can replace the MOS tube, with lower cost, further reducing the production cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the scheme in the utility model, a brief introduction is given below to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 It is a schematic diagram of the structure of the display screen detection circuit providing VCC and VDD dual voltages of the utility model;

[0024] The markings in the figure are as follows: 1. Boost module; 11. Boost chip; 12. Boost output terminal; 13. Boost input terminal; 2. Control switch module; 21. MOS tube. DETAILED DESCRIPTION

[0025] In order to enable those skilled in the art to better understand the solution of the utility model, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is only a part of the embodiment of the utility model, not all of the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the utility model.

[0026] As described in the background technology, the prior art requires at least two voltages to be provided externally for display screens, such as PMOLED display screens and STN display screens, to drive the display screens, of which the following two are necessary: ​​VDD and VCC. Among them, VDD is used to drive the display screen driver IC, which is generally 3.3V or 3.0V. VCC is used to drive glass display, PMOLED display screens are used to drive OLED, and STN display screens are used to drive liquid crystal flipping. The VCC voltage is generally above 10V or close to 10V. The above two voltages have control over the power-on and power-off sequence. When powering on: first turn on the low voltage, then the high voltage. When powering off, first turn off the high voltage, then the low voltage. For the control of this sequence, the current testing method is to control the power-on and power-off sequence by manually controlling the power switch by the employee. During the test process, negligence or inattention in the operation may cause the power-on and power-off sequence to be wrong, and problems may occur, which cannot be prevented.

[0027] In order to solve this technical problem, the utility model provides a display screen detection circuit that provides VCC and VDD dual voltages, including a boost module 1 and a control switch module 2. The boost module 1 includes a boost chip 11, a boost output terminal 12 and a boost input terminal 13. The boost output terminal 12 is coupled to the VCC terminal, and the boost input terminal 13 is coupled to the control switch module 2. The control switch module 2 includes a switch tube. The switch tube is a MOS tube 21, the drain of the MOS tube 21 is coupled to the boost input terminal 13, the source of the MOS tube 21 is coupled to the VDD terminal, and the gate of the MOS tube 21 is coupled to the enable control terminal VCC_EN terminal. The model of the boost chip 11 is AP3015KTR-G1.

[0028] Through the above structural design, the display screen detection circuit that provides dual voltages of VCC and VDD controls the signal through the MOS tube 21. When the MOS tube 21 is turned on, the boost module 1 has an input voltage, boosts VCC normally, and the display module is connected to the VCC voltage. When the MOS tube 21 is turned off, the boost module 1 has no input voltage, cannot boost VCC, and the display module disconnects the VCC voltage. In this way, by controlling the working state through the MOS tube 21, the power-on and power-off sequence of VDD and VCC can be controlled by circuits and signals, so as to be foolproof, reliable, easy to operate, and highly practical.

[0029] In order to enable those skilled in the art to better understand the present invention, the technical solutions in the embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0030] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features and technical solutions in the embodiments may be combined with each other.

[0031] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0032] like Figure 1 As shown, the display screen detection circuit providing VCC and VDD dual voltages includes a boost module 1 and a control switch module 2. The boost module 1 includes a boost chip 11, a boost output terminal 12 and a boost input terminal 13. The boost output terminal 12 is coupled to the VCC terminal, and the boost input terminal 13 is coupled to the control switch module 2. The control switch module 2 includes a switch tube.

[0033] The switch tube is a MOS tube 21 , the drain of the MOS tube 21 is coupled to the boost input terminal 13 , the source of the MOS tube 21 is coupled to the VDD terminal, and the gate of the MOS tube 21 is coupled to the enable control terminal VCC_EN terminal.

[0034] It should be noted that the model of the boost chip 11 is AP3015KTR-G1.

[0035] A coupling capacitor C7 is provided between the boost output terminal 12 and the ground line.

[0036] A coupling capacitor C6 is provided between the boost input terminal 13 and the ground line.

[0037] The voltage of the VDD terminal is 3.3 V. The voltage of the VDD terminal is 3.0 V.

[0038] The working mode of this embodiment is described below.

[0039] The display screen detection circuit that provides dual voltages of VCC and VDD controls the signal through the MOS tube 21. When the MOS tube 21 is turned on, the boost module 1 has an input voltage, boosts VCC normally, and the display module is connected to the VCC voltage. When the MOS tube 21 is turned off, the boost module 1 has no input voltage, cannot boost VCC, and the display module disconnects the VCC voltage. In this way, by controlling the working state through the MOS tube 21, the power-on and power-off sequence of VDD and VCC can be controlled by circuits and signals, so as to be foolproof, reliable, easy to operate, and highly practical.

[0040] The display screen detection circuit providing dual voltages of VCC and VDD provided in Embodiment 1 or 2 is further optimized. Specifically, the SW pin of the boost chip 11 is coupled to the VCC terminal via a diode D1.

[0041] An inductor L1 is provided between the SW pin and the VIN pin of the boost chip 11 .

[0042] The working mode of this embodiment is described below.

[0043] Diode D1 can effectively prevent abnormal current from flowing back from the VCC terminal, thus protecting the circuit safety.

[0044] The display screen detection circuit providing dual voltages of VCC and VDD provided in Example 1 is further optimized. Specifically, the switch tube is a triode.

[0045] The working mode of this embodiment is described below.

[0046] The MOS tube 21 can be replaced by a triode, which has a lower cost and further reduces the production cost.

[0047] In addition, the transistor is a field effect transistor or a triode. When these crystals are field effect transistors, they can be N-type transistors (such as metal-oxide-semiconductor field effect transistors (N-Metal-Oxide-Semiconductor, NMOS)), or P-type metal-oxide-semiconductor field effect transistors, complementary metal-oxide-semiconductor field effect transistors, and other circuit structure types.

[0048] The terms "coupling" and "coupling" involved in the embodiments of the present application should be understood in a broad sense. For example, they may refer to a direct physical connection, or an indirect connection achieved through electronic devices, such as a connection achieved through resistors, inductors, capacitors or other electronic devices.

[0049] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0050] Obviously, the embodiments described above are only some embodiments of the present application, rather than all embodiments. The preferred embodiments of the present application are given in the accompanying drawings, but they do not limit the patent scope of the present application. The present application can be implemented in many different forms. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present application more thorough and comprehensive. Although the present application is described in detail with reference to the aforementioned embodiments, for those skilled in the art, it is still possible to modify the technical solutions recorded in the aforementioned specific implementation methods, or to replace some of the technical features therein with equivalents. Any equivalent structure made using the contents of the specification and drawings of this application, directly or indirectly used in other related technical fields, is also within the scope of patent protection of this application.

Claims

1. A display screen detection circuit providing VCC and VDD dual voltages, characterized in that: The display screen detection circuit providing dual voltages of VCC and VDD comprises a boost module (1) and a control switch module (2); the boost module (1) comprises a boost chip (11), a boost output terminal (12) and a boost input terminal (13); the boost output terminal (12) is coupled to the VCC terminal; the boost input terminal (13) is coupled to the control switch module (2); and the control switch module (2) comprises a switch tube.

2. The display screen detection circuit providing dual voltages of VCC and VDD according to claim 1, characterized in that: The switch tube is a MOS tube (21), the drain of the MOS tube (21) is coupled to the boost input terminal (13), the source of the MOS tube (21) is coupled to the VDD terminal, and the gate of the MOS tube (21) is coupled to the enable control terminal VCC_EN terminal.

3. The display screen detection circuit providing dual voltages of VCC and VDD according to claim 1, characterized in that: The switch tube is a triode.

4. The display screen detection circuit providing dual voltages of VCC and VDD according to claim 1, characterized in that: The model of the boost chip (11) is AP3015KTR-G1.

5. The display screen detection circuit providing dual voltages of VCC and VDD according to claim 1, characterized in that: A coupling capacitor C7 is provided between the boost output terminal (12) and the ground line.

6. The display screen detection circuit providing dual voltages of VCC and VDD according to claim 1, characterized in that: A coupling capacitor C6 is provided between the boost input terminal (13) and the ground line.

7. The display screen detection circuit providing dual voltages of VCC and VDD according to claim 2, characterized in that: The SW pin of the boost chip (11) is coupled to the VCC terminal via a diode D1.

8. The display screen detection circuit providing dual voltages of VCC and VDD according to claim 2, characterized in that: An inductor L1 is provided between the SW pin and the VIN pin of the boost chip (11).

9. The display screen detection circuit providing dual voltages of VCC and VDD according to claim 2, characterized in that: The voltage of the VDD terminal is 3.3V.

10. The display screen detection circuit providing dual voltages of VCC and VDD according to claim 2, characterized in that: The voltage of the VDD terminal is 3.0V.

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