Overvoltage protection device of test board
By setting up a step-down module, filtering and voltage division unit at the power input port of the test board, the problem of overvoltage burnout of the test board is solved, and overvoltage protection of the test board is achieved to ensure the smooth progress of the test work.
Patent Information
- Application Number
- CN202421786813.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-25
- Publication Date
- 2025-07-11
- Estimated Expiration
- 2034-07-25
AI Technical Summary
During the display screen testing, the test board is easily burned out by the excessive voltage of the external DC power supply due to lack of overvoltage protection, resulting in the inability to complete the test.
Design an overvoltage protection device for the test board, which is directly connected to the power input port of the test board through a buck module, and filter and divide the input voltage by using a filter unit and a voltage divider to ensure that the voltage is transmitted to the test board within a safe range.
Effectively prevent the test board from burning out due to excessive voltage and ensure the normal progress of the test.
Smart Images
Figure CN223093488U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of display screens, in particular to an overvoltage protection device for a test board. Background Art
[0002] At present, display screens are widely used, such as monitors, telephones, handheld scanners, cameras, etc.
[0003] In the related art, display screens need to be tested before leaving the factory. In the testing process, the test board needs to be powered on first, and then the display screen is lit by the test board. However, the rated voltage of the test board is 6.5V and there is no overvoltage protection. When the externally connected DC power supply is suddenly too high, the test board is easily burned out, resulting in the inability to complete the test work. Summary of the Utility Model
[0004] The purpose of the utility model is to overcome the deficiencies in the prior art and provide an overvoltage protection device for a test board, which can provide overvoltage protection for the test board and prevent the test board from being burned out due to excessive DC power supply.
[0005] The purpose of the utility model is realized by the following technical solutions:
[0006] The first aspect of the present application provides an overvoltage protection device for a test board, including: a board body, on which a power input port is provided, and the power input port is used for electrically connecting with a DC power supply; a step-down module, which includes an input end, a chip U3, a filtering unit and a voltage dividing unit. The input end is electrically connected with the power input port, the chip U3 is electrically connected with the input end, and the filtering unit and the voltage dividing unit are respectively electrically connected with the chip U3.
[0007] The filtering unit includes a capacitor C2, the first end of the capacitor C2 is electrically connected with the input end, and the second end of the capacitor C2 is electrically connected with the chip U3.
[0008] The filtering unit further includes a capacitor C1, and the first end of the capacitor C1 is electrically connected with the chip U3.
[0009] The voltage dividing unit includes an inductor L1, and the second end of the capacitor C1 is electrically connected with the first end of the inductor L1.
[0010] The voltage dividing unit further includes a diode D1, the first end of the diode D1 is electrically connected with the chip U3, and the second end of the diode D1 is grounded.
[0011] The voltage dividing unit further includes a resistor R1 and a resistor R3. The first end of the resistor R1 is electrically connected to the second end of the inductor L1. The second end of the resistor R1 is electrically connected to the first end of the resistor R3. The second end of the resistor R3 is grounded.
[0012] The voltage dividing unit further includes a resistor R2. The first end of the resistor R2 is electrically connected to the first end of the resistor R1.
[0013] The voltage dividing unit further includes a MOS transistor Q2. The MOS transistor Q2 is electrically connected to the second end of the resistor R2.
[0014] The buck module further includes a capacitor C3 and a capacitor C4. The first end of the capacitor C3 is electrically connected to the second end of the inductor L1. The second end of the capacitor C3 is grounded. The first end of the capacitor C4 is electrically connected to the first end of the capacitor C3. The second end of the capacitor C4 is grounded.
[0015] The buck module further includes an output terminal. The output terminal is electrically connected to the first end of the capacitor C4.
[0016] Compared with the prior art, the present utility model has at least the following advantages:
[0017] By providing a buck module, the buck module is directly electrically connected to the power input port of the test board, so that the voltage input from the DC power supply is first stepped down by the buck module and then transmitted to other modules, thereby ensuring that the test board will not be burned out due to excessive voltage. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings required to be used in the embodiments will be briefly introduced below.
[0019] Figure 1 It is a schematic structural diagram of an overvoltage protection device for a test board in an embodiment of the present utility model;
[0020] Figure 2 It is a circuit diagram of an overvoltage protection device for a test board in an embodiment of the present utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0021] The embodiments of the present application will be described in more detail with reference to the drawings. Although the embodiments of the present application are shown in the drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to make the present application more thorough and complete, and to fully convey the scope of the present application to those skilled in the art.
[0022] It should be understood that although the terms "first", "second", "third", etc. may be used in this application to describe various information, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from each other. For example, without departing from the scope of this application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of this application, the meaning of "a plurality" is two or more unless otherwise specifically defined.
[0023] Unless otherwise clearly stipulated and defined, terms such as "installed", "connected", "joined", "fixed", etc. shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0024] In the related art, the display screen needs to be tested before leaving the factory. In the testing process, the test board needs to be powered on first, and then the display screen is lit by the test board. However, the rated voltage of the test board is 6.5V and there is no overvoltage protection. When the externally connected DC power supply suddenly becomes too high, it is easy to burn out the test board, resulting in the inability to complete the test work.
[0025] In view of the above problems, the embodiment of this application provides an overvoltage protection device for a test board, which can provide overvoltage protection for the test board and prevent the test board from being burned out due to excessive DC power supply.
[0026] The technical solutions of the embodiments of this application will be described in detail below with reference to the accompanying drawings.
[0027] Please refer to Figure 1 and Figure 2 , an overvoltage protection device for a test board, including: a board body 100 and a step-down module 200. A power input port 110 is provided on the board body 100, and the power input port 110 is used for electrically connecting to a DC power supply; the step-down module 200 includes an input end, a chip U3, a filtering unit and a voltage dividing unit. The input end is electrically connected to the power input port 110, the chip U3 is electrically connected to the input end, and the filtering unit and the voltage dividing unit are respectively electrically connected to the chip U3.
[0028] It should be noted that by setting the voltage reduction module 200, the voltage reduction module 200 is directly electrically connected to the power input port 110110 of the test board, so that the voltage input by the DC power supply is first reduced by the voltage reduction module 200 and then transmitted to other modules, thereby ensuring that the test board will not be burned out due to excessive voltage. Further, the filtering unit functions to filter out the ripples in the circuit, and the voltage dividing unit is used for voltage division, and the voltage range at the input end is between 5V and 40V.
[0029] Please refer to Figure 2 , in an embodiment, the filtering unit includes a capacitor C2, a first end of the capacitor C2 is electrically connected to the input end, and a second end of the capacitor C2 is electrically connected to the chip U3. Specifically, the filtering unit further includes a capacitor C1, and a first end of the capacitor C1 is electrically connected to the chip U3.
[0030] It should be noted that the capacitor C2 and the capacitor C1 function to filter.
[0031] Please refer to Figure 2 , in an embodiment, the voltage dividing unit includes an inductor L1, and a second end of the capacitor C1 is electrically connected to a first end of the inductor L1.
[0032] It should be noted that the inductor L1 functions to smooth the current, reduce power consumption and heat loss, and stabilize the output voltage.
[0033] Please refer to Figure 2 , in an embodiment, the voltage dividing unit further includes a diode D1, a first end of the diode D1 is electrically connected to the chip U3, and a second end of the diode D1 is grounded.
[0034] It should be noted that the diode D1 functions to keep the inductor current continuous.
[0035] Please refer to Figure 2 , in an embodiment, the voltage dividing unit further includes a resistor R1 and a resistor R3, a first end of the resistor R1 is electrically connected to a second end of the inductor L1, a second end of the resistor R1 is electrically connected to a first end of the resistor R3, and a second end of the resistor R3 is grounded. Specifically, the voltage dividing unit further includes a resistor R2, and a first end of the resistor R2 is electrically connected to the first end of the resistor R1.
[0036] It should be noted that the resistor R1, the resistor R2, and the resistor R3 are all voltage dividing resistors.
[0037] Please refer to Figure 1 , in an embodiment, the voltage dividing unit further includes a MOS transistor Q2, and the MOS transistor Q2 is electrically connected to a second end of the resistor R2. Specifically, the voltage reduction module 200 further includes an output end, and the output end is electrically connected to a first end of the capacitor C4.
[0038] It should be noted that the MOS transistor Q2 is a switch. When a lower voltage needs to be output at the output end, the MOS transistor Q2 can be turned on.
[0039] Please refer to Figure 1 , in an embodiment, the buck module 200 further includes a capacitor C3 and a capacitor C4. The first end of the capacitor C3 is electrically connected to the second end of the inductor L1, the second end of the capacitor C3 is grounded, the first end of the capacitor C4 is electrically connected to the first end of the capacitor C3, and the second end of the capacitor C4 is grounded.
[0040] It should be noted that both the capacitor C3 and the capacitor C4 function for filtering, storing energy, and stabilizing the output voltage.
[0041] It should be understood that the buck principle of the present application is as follows: After the voltage enters from the input end, through the voltage division of the resistors R1, R2, and R3, the reduced voltage is output from the output end to other modules of the test board. Specifically, the voltage output formula at the output end is: the output value is equal to 0.6 multiplied by the sum of the resistors R1 and R2, the product obtained is divided by the resistor R3, and the quotient obtained plus 0.6 is the voltage at the output end. Among them, 0.6 is a fixed parameter of each chip U3, and the coefficients of different models of chips are different.
[0042] The solution of the present application has been described in detail above with reference to the accompanying drawings. In the above embodiments, the descriptions of each embodiment have their own focuses. For the parts not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments. Those skilled in the art should also be aware that the actions and modules involved in the specification are not necessarily essential to the present application. In addition, it can be understood that the steps in the method embodiments of the present application can be adjusted, combined, and deleted according to actual needs, and the modules in the device embodiments of the present application can be combined, divided, and deleted according to actual needs.
[0043] The various embodiments of the present application have been described above. The above description is exemplary and not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations are obvious to those of ordinary skill in the art in the technical field without departing from the scope and spirit of the described embodiments. The choice of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other ordinary skilled in the art in the technical field to understand the disclosed embodiments.
Claims
1. An overvoltage protection device for a test board, characterized in that, Comprising: A plate body, on which a power input port is provided, and the power input port is used for electrically connecting to a DC power supply; A step-down module, the step-down module includes an input end, a chip U3, a filtering unit and a voltage dividing unit, the input end is electrically connected to the power input port, the chip U3 is electrically connected to the input end, and the filtering unit and the voltage dividing unit are respectively electrically connected to the chip U3.
2. The overvoltage protection device for the test board according to claim 1, characterized in that, The filtering unit includes a capacitor C2, a first end of the capacitor C2 is electrically connected to the input end, and a second end of the capacitor C2 is electrically connected to the chip U3.
3. The overvoltage protection device of the test board according to claim 2, characterized in that, The filtering unit further includes a capacitor C1, and a first end of the capacitor C1 is electrically connected to the chip U3.
4. The overvoltage protection device of the test board according to claim 3, characterized in that, The voltage dividing unit includes an inductor L1, and a second end of the capacitor C1 is electrically connected to a first end of the inductor L1.
5. The overvoltage protection device for a test board according to claim 1, characterized in that The voltage dividing unit further includes a diode D1, a first end of the diode D1 is electrically connected to the chip U3, and a second end of the diode D1 is grounded.
6. The overvoltage protection device for the test board according to claim 4, characterized in that, The voltage dividing unit further includes a resistor R1 and a resistor R3, a first end of the resistor R1 is electrically connected to a second end of the inductor L1, a second end of the resistor R1 is electrically connected to a first end of the resistor R3, and a second end of the resistor R3 is grounded.
7. The overvoltage protection device of the test board according to claim 6, characterized in that, The voltage dividing unit further includes a resistor R2, and a first end of the resistor R2 is electrically connected to the first end of the resistor R1.
8. The overvoltage protection device for a test board according to claim 7, wherein, The voltage dividing unit further includes a MOS transistor Q2, and the MOS transistor Q2 is electrically connected to a second end of the resistor R2.
9. The overvoltage protection device for a test board according to claim 7, characterized in that, The step-down module further includes a capacitor C3 and a capacitor C4, a first end of the capacitor C3 is electrically connected to the second end of the inductor L1, a second end of the capacitor C3 is grounded, a first end of the capacitor C4 is electrically connected to the first end of the capacitor C3, and a second end of the capacitor C4 is grounded.
10. The overvoltage protection device of the test board according to claim 9, characterized in that, The step-down module further includes an output end, and the output end is electrically connected to the first end of the capacitor C4.