Backlight module test circuit capable of adjusting current and backlight module test system

Abstract

The embodiment of the utility model provides a backlight module test circuit capable of adjusting current and a backlight module test system, and the backlight module test circuit comprises a constant current power supply chip which is connected with a first end of an external voltage stabilization DC power supply and a first end of a backlight module and is used for providing current for the backlight module; the adjustable resistance module is connected between the grounding end of the external voltage-stabilizing direct-current power supply and the second end of the backlight module, and the adjustable resistance module is used for adjusting the magnitude of current flowing through the backlight module; the adjustable resistor module comprises at least one adjustable resistor unit, the adjustable resistor unit comprises at least one resistor and at least one first toggle switch, and when the at least one first toggle switch is connected with the at least one resistor, the adjustable resistor module is conducted. According to the backlight module test circuit capable of adjusting the current and the backlight module test system, the current output to the backlight module can be conveniently adjusted.

Description

Technical Field

[0001] This application relates to the technical field of liquid crystal display screens, and more specifically, to a backlight module test circuit and a backlight module test system with adjustable current. Background Art

[0002] In the backlight test rack used in the production process of liquid crystal display screens, a constant current power supply is used to supply power to the backlight module. The magnitude of the current output by the test rack is determined by the feedback resistor in the power supply circuit. When testing backlight modules with different current specifications, it is necessary to adjust the magnitude of the feedback resistor in the circuit to adjust the magnitude of the output current. A simple method is to use a precision adjustable resistor as the feedback resistor. Although this can adjust the output current, it cannot accurately adjust the output current. Utility Model Content

[0003] The purpose of the embodiments of this application is to provide a backlight module test circuit and a backlight module test system with adjustable current, which can conveniently adjust the current output to the backlight module.

[0004] In a first aspect, the embodiments of this application provide a backlight module test circuit with adjustable current, including:

[0005] A constant current power supply chip, connected to the first end of an external regulated DC power supply and the first end of the backlight module, for providing current to the backlight module;

[0006] An adjustable resistor module, connected between the ground terminal of the external regulated DC power supply and the second end of the backlight module, and the adjustable resistor module is used to adjust the magnitude of the current flowing through the backlight module;

[0007] The adjustable resistor module includes at least one adjustable resistor unit, and the adjustable resistor unit includes: at least one resistor and at least one first toggle switch. When the at least one first toggle switch is connected to the at least one resistor, the adjustable resistor module is turned on.

[0008] In the above implementation process, the adjustable resistor module is connected between the ground terminal of the external regulated DC power supply and the second end of the backlight module. The adjustable resistor module is used to adjust the magnitude of the current flowing through the backlight module. The adjustable resistor module includes at least one adjustable resistor unit, and the adjustable resistor unit includes: at least one resistor and at least one first toggle switch. When the at least one first toggle switch is connected to the at least one resistor, the adjustable resistor module is turned on. By toggling the first toggle switch, the first toggle switch is connected to different resistors, thereby accurately adjusting the magnitude of the current input to the backlight module.

[0009] Further, there are multiple adjustable resistor units;

[0010] At least one first toggle switch of each adjustable resistor unit is connected to the ground terminal of the external regulated DC power supply, and at least one resistor of each adjustable resistor unit is connected to the second terminal of the backlight module.

[0011] In the above implementation process, by toggling the first toggle switches of different adjustable resistor units, the first toggle switches are connected to different resistors, thereby adjusting the magnitude of the current input to the backlight module.

[0012] Furthermore, there are multiple adjustable resistor units;

[0013] At least one first toggle switch of each adjustable resistor unit is connected to the second terminal of the backlight module, and at least one resistor of each adjustable resistor unit is connected to the ground terminal of the external regulated DC power supply.

[0014] In the above implementation process, by toggling the first toggle switches of different adjustable resistor units, the first toggle switches are connected to different resistors, thereby adjusting the magnitude of the current input to the backlight module.

[0015] Furthermore, the adjustable resistor module is composed of one adjustable resistor unit;

[0016] When at least one first toggle switch in the adjustable resistor unit of the adjustable resistor module is connected to the at least one resistor, the adjustable resistor unit is turned on.

[0017] Furthermore, the backlight module test circuit with adjustable current includes: a toggle switch group;

[0018] The adjustable resistor module is connected to the second terminal of the backlight module through the toggle switch group;

[0019] The toggle switch group has at least one toggle switch unit;

[0020] The toggle switch unit includes at least one second toggle switch;

[0021] The toggle switch group is connected to the adjustable resistor module through the toggle end of the second toggle switch;

[0022] When at least one toggle switch in each toggle switch unit is closed, the toggle switch group turns on the second terminal of the backlight module and the adjustable resistor module;

[0023] At least one adjustable resistor unit in the adjustable resistor module can be conductively connected to the second terminal of the optical module through the toggle switch group.

[0024] In the above implementation process, the test circuit of the backlight module with adjustable current includes: a toggle switch group; the adjustable resistor module is connected to the second end of the backlight module through the toggle switch group; the toggle switch group has at least one toggle switch unit; the toggle switch unit includes at least one second toggle switch; the toggle switch group is connected to the adjustable resistor module through the toggle end of the second toggle switch; when at least one toggle switch in each toggle switch unit is closed, the toggle switch group conducts the second end of the backlight module and the adjustable resistor module. Based on this, the number of resistors set can be further increased through the toggle switch group.

[0025] Further, each of the adjustable resistor units can be conductively connected to the second end of the light module through the toggle switch group.

[0026] In the above implementation process, the flexibility of adjusting the backlight current can be maximally improved by expanding the toggle switch group to connect different adjustable resistor units and the second end of the light module.

[0027] Further, there are multiple toggle switch units;

[0028] The multiple toggle switch units are connected in series with each other. The toggle switch unit at the first end of the toggle switch group is connected to the second end of the backlight module, and the toggle switch unit at the second end of the toggle switch group is connected to the adjustable resistor module.

[0029] In the above implementation process, the flexibility of adjusting the backlight current can be maximally improved by expanding the number of series-connected toggle switch groups to connect different adjustable resistor units and the second end of the light module.

[0030] Further, the number of the second toggle switches in all the toggle switch units in the toggle switch group forms a geometric sequence, and the common ratio of the geometric sequence is the same as the number of channels of the second toggle switch.

[0031] In the above implementation process, the second toggle switch can be maximally utilized to control the separate connection of different adjustable resistor units and the second end of the backlight module.

[0032] Further, the first end of the adjustable resistor module is connected to the ground terminal of the external regulated DC power supply;

[0033] The second end of the adjustable resistor module is connected to the second end of the backlight module and the feedback voltage output terminal of the constant current power supply chip.

[0034] In the above implementation process, the magnitude of the current input to the backlight module can be calculated through the feedback voltage and the resistance.

[0035] Second aspect, the present application provides a backlight module testing system, including: a backlight module; the adjustable current backlight module testing circuit described in the first aspect. Description of the Drawings

[0036] To more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required to be used in the embodiments of the present application. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other relevant drawings can also be obtained based on these drawings.

[0037] Figure 1 Structural schematic diagram of the adjustable current backlight module testing circuit provided by the embodiment of the present application;

[0038] Figure 2 Another structural schematic diagram of the adjustable current backlight module testing circuit provided by the embodiment of the present application. Detailed Embodiments

[0039] The following will describe the technical solutions in the embodiments of the present application in conjunction with the drawings in the embodiments of the present application.

[0040] It should be noted that: similar reference numerals and letters represent similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of the present application, the terms "first", "second", etc. are only used for distinguishing descriptions, and cannot be understood as indicating or implying relative importance.

[0041] Embodiment 1

[0042] The embodiment of the present application provides an adjustable current backlight module testing circuit, including:

[0043] A constant current power supply chip, connected to the first end of the external regulated DC power supply and the first end of the backlight module, for providing current to the backlight module;

[0044] An adjustable resistor module, connected between the ground terminal of the external regulated DC power supply (the second end of the external regulated DC power supply) and the second end of the backlight module. The adjustable resistor module is used to adjust the magnitude of the current flowing through the backlight module;

[0045] The adjustable resistor module includes at least one adjustable resistor unit. The adjustable resistor unit includes: at least one resistor and at least one first toggle switch. When at least one first toggle switch is connected to at least one resistor, the adjustable resistor module is turned on.

[0046] Exemplarily, see Figure 1 , exemplarily, seeFigure 1 , is a schematic diagram of the connection of a backlight module test circuit with adjustable current, a backlight module, and an external regulated DC power supply; wherein, the first terminal LED+ of the backlight module is connected to the first terminal DCIN of the external regulated DC power supply through a diode D1, an inductor L1; both ends of the inductor L1 are also connected to the IN and LX pins of a constant current power supply chip (such as the chip SY7200 of SILERGY) U1; the OVP pin of the constant current power supply chip U1 is connected to the first terminal LED+ of the backlight module; the ground terminal of the constant current power supply chip U1 is grounded; the ground terminal of the constant current power supply chip U1 and the first terminal LED+ of the backlight module are connected with a capacitor C1; the second terminal LED- of the backlight module is connected to the VF pin of the constant current power supply chip U1; the EN pin of the constant current power supply chip U1 is also connected to the first terminal DCIN of the external regulated DC power supply through a resistor R1.

[0047] The adjustable resistor module has an adjustable resistor unit, and the adjustable resistor unit includes: a resistor R1, a resistor R2, a resistor R3, a resistor R4, and a toggle switch SW (the first toggle switch). When the first toggle switch is toggled to different resistors, the second terminal LED- of the backlight module is connected to the external DC regulated power supply through different resistors. Since the external DC regulated power supply provides a stable voltage, the current flowing through the backlight module changes with the connected resistor.

[0048] In the above implementation process, the adjustable resistor module is connected between the ground terminal of the external regulated DC power supply and the second terminal of the backlight module. The adjustable resistor module is used to adjust the magnitude of the current flowing through the backlight module. The adjustable resistor module includes at least one adjustable resistor unit. The adjustable resistor unit includes: at least one resistor and at least one first toggle switch. When at least one first toggle switch is connected to at least one resistor, the adjustable resistor module is turned on. By toggling the first toggle switch, the first toggle switch is connected to different resistors, thereby adjusting the magnitude of the current input to the backlight module.

[0049] In some embodiments, there are multiple adjustable resistor units;

[0050] At least one first toggle switch of each adjustable resistor unit is connected to the ground terminal of the external regulated DC power supply, and at least one resistor of each adjustable resistor unit is connected to the second terminal of the backlight module.

[0051] Exemplarily, refer to Figure 2, a toggle switch SW2 (the first toggle switch), a resistor R2, a resistor R3, a resistor R4, and a resistor R5 form an adjustable resistor unit; a toggle switch SW3 (the first toggle switch), a resistor R6, a resistor R7, a resistor R8, and a resistor R9 form an adjustable resistor unit; a toggle switch SW4 (the first toggle switch), a resistor R10, a resistor R11, a resistor R12, and a resistor R13 form an adjustable resistor unit; a toggle switch SW5 (the first toggle switch), a resistor R14, a resistor R15, a resistor R16, and a resistor R17 form an adjustable resistor unit.

[0052] In this application, the toggle end of the first toggle switch is connected to the resistor. By toggling the toggle end of the adjustable resistor unit, the toggle end can be connected to different resistors in the adjustable resistor unit.

[0053] Exemplarily, by toggling the toggle end of the toggle switch SW2, the toggle switch SW2 can be connected to the resistor R2, the resistor R3, or the resistor R4.

[0054] In the above implementation process, by toggling the first toggle switches of different adjustable resistor units, the first toggle switches are connected to different resistors, thereby adjusting the magnitude of the current input to the backlight module.

[0055] In some embodiments, there are multiple adjustable resistor units;

[0056] At least one first toggle switch of each adjustable resistor unit is connected to the second end of the backlight module, and at least one resistor of each adjustable resistor unit is connected to the ground terminal of the external regulated DC power supply.

[0057] In the above implementation process, by toggling the first toggle switches of different adjustable resistor units, the first toggle switches are connected to different resistors, thereby adjusting the magnitude of the current input to the backlight module.

[0058] In some embodiments, the adjustable resistor module is composed of one adjustable resistor unit;

[0059] When at least one first toggle switch and at least one resistor in the adjustable resistor unit of the adjustable resistor module are connected, the adjustable resistor unit is turned on.

[0060] In some embodiments, a backlight module test circuit for adjusting current includes: a toggle switch group;

[0061] The adjustable resistor module is connected to the second end of the backlight module through a toggle switch group; the toggle switch group has at least one toggle switch unit; the toggle switch unit includes at least one second toggle switch; the toggle switch group is connected to the adjustable resistor module through the toggle end of the second toggle switch; when at least one toggle switch in each toggle switch unit is closed, the toggle switch group conducts the second end of the backlight module and the adjustable resistor module; at least one adjustable resistor unit in the adjustable resistor module can be conductively connected to the second end of the light module through the toggle switch group.

[0062] Exemplarily, referring to Figure 2 , the toggle switch group has one toggle switch unit, and the toggle switch unit has one second toggle switch, which is toggle switch SW1. By toggling toggle switch SW1 and connecting it to toggle switch SW1, toggle switch SW2, toggle switch SW3, or toggle switch SW4, different adjustable resistor units can be connected to the second end of the backlight module.

[0063] In the above implementation process, the backlight module test circuit for adjusting current includes: a toggle switch group; the adjustable resistor module is connected to the second end of the backlight module through the toggle switch group; the toggle switch group has at least one toggle switch unit; the toggle switch unit includes at least one second toggle switch; the toggle switch group is connected to the adjustable resistor module through the toggle end of the second toggle switch; when at least one toggle switch in each toggle switch unit is closed, the toggle switch group conducts the second end of the backlight module and the adjustable resistor module. Based on this, the number of set resistors can be further increased through the toggle switch group.

[0064] In some embodiments, each adjustable resistor unit can be conductively connected to the second end of the light module through the toggle switch group.

[0065] Exemplarily, referring to Figure 1 , Figure 2 each resistor in

[0066] In the above implementation process, different adjustable resistor units and the second end of the light module can be connected by expanding the toggle switch group, maximizing the flexibility of adjusting the backlight current.

[0067] In some embodiments, there are multiple toggle switch units;

[0068] The multiple toggle switch units are connected in series with each other. The toggle switch unit at the first end of the toggle switch group is connected to the second end of the backlight module, and the toggle switch unit at the second end of the toggle switch group is connected to the adjustable resistor module.

[0069] In the above implementation process, the flexibility of adjusting the backlight current can be maximally improved by expanding the number of series-connected toggle switch groups for different adjustable resistor units and the second ends of the optical module groups.

[0070] In some embodiments, the number of second toggle switches of all toggle switch units in the toggle switch group forms a geometric sequence, and the common ratio of the geometric sequence is the same as the number of channels of the second toggle switch.

[0071] In some embodiments, the number of channels of the second toggle switch is k (k is a positive integer), the number of second toggle switches of the first toggle switch unit is 1, the number of second toggle switches of the second toggle switch unit is 4,... the number of second toggle switches of the nth toggle switch unit is k n-1 , where n is an integer greater than or equal to 1. The toggle end of the second toggle switch of the (n - 1)th toggle switch unit can be connected to the fixed end of the nth toggle switch unit, and any two second toggle switches in the (n - 1)th toggle switch unit cannot be connected to the same second toggle switch in the nth toggle switch unit; the fixed ends of the second toggle switches in the nth toggle switch unit (when n > 1) are all connected to the toggle ends of the second toggle switches of the (n - 1)th toggle switch unit; the fixed end of the first toggle switch is connected to the second end of the backlight module; the toggle end of the second toggle switch of the nth toggle switch unit can be connected to the adjustable resistor unit in the adjustable resistor module; the toggle end of the second toggle switch of the nth toggle switch unit is used to be connected to the first toggle switch of the adjustable resistor unit in the adjustable resistor module; any two second toggle switches of the nth toggle switch unit cannot be connected to the same adjustable resistor unit; the fixed end of the first toggle switch of each adjustable resistor unit can be connected to the toggle end of a second toggle unit of the nth toggle switch unit.

[0072] The toggle end is the end that can be toggled to cut off the connection object of the toggle switch, and the fixed end is the other end except the toggle end.

[0073] In the above implementation process, the second toggle switch can be maximally utilized to control the separate connection of different adjustable resistor units and the second end of the backlight module.

[0074] In some embodiments, the first end of the adjustable resistor module is connected to the ground terminal of the external regulated DC power supply;

[0075] The second end of the adjustable resistor module is connected to the second end of the backlight module and the feedback voltage output terminal of the constant current power supply chip.

[0076] Exemplarily, according to the rated current of different backlight modules, as long as the resistors connected to each path are set according to the formula that the output current is equal to the reference voltage divided by the feedback resistor, different output current values can be preset. When it is necessary to change the output current, as long as the switch is toggled to select the corresponding channel, the output current can be immediately adjusted to the predetermined value, realizing fast quantitative adjustment of the output current without the need for an additional current detection instrument to detect the magnitude of the output current.

[0077] In the above implementation process, the magnitude of the current input to the backlight module can be calculated through the feedback voltage and resistance.

[0078] The present application provides a backlight module test system, including: a backlight module; the above-mentioned backlight module test circuit with adjustable current.

[0079] Without contradiction, the embodiments of the present application can be arbitrarily combined to form new embodiments.

[0080] The above are only the embodiments of the present application and are not used to limit the protection scope of the present application. For those skilled in the art, the present application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application. It should be noted that similar reference numerals and letters indicate similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0081] The above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed by the present application, and all should be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

[0082] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "including", "comprising" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, the element defined by the statement "including one..." does not exclude the existence of additional identical elements in the process, method, article or device including the said element.

Claims

1. An adjustable current backlight module test circuit, characterized in that Comprising: A constant current power supply chip, connected to the first end of an external regulated DC power supply and the first end of the backlight module, for providing current to the backlight module; An adjustable resistor module, connected between the ground terminal of the external regulated DC power supply and the second end of the backlight module, the adjustable resistor module being used to adjust the magnitude of the current flowing through the backlight module; The adjustable resistor module includes at least one adjustable resistor unit, and the adjustable resistor unit includes: at least one resistor and at least one first toggle switch. When the at least one first toggle switch is connected to the at least one resistor, the adjustable resistor module is turned on.

2. The backlight module test circuit with adjustable current according to claim 1, characterized in that, There are multiple of the adjustable resistor units; At least one first toggle switch of each adjustable resistor unit is connected to the ground terminal of the external regulated DC power supply, and at least one resistor of each adjustable resistor unit is connected to the second end of the backlight module.

3. The backlight module test circuit with adjustable current according to claim 1, wherein There are multiple of the adjustable resistor units; At least one first toggle switch of each adjustable resistor unit is connected to the second end of the backlight module, and at least one resistor of each adjustable resistor unit is connected to the ground terminal of the external regulated DC power supply.

4. The adjustable current backlight module test circuit according to claim 1, wherein The adjustable resistor module is composed of one adjustable resistor unit; When at least one first toggle switch in the adjustable resistor unit of the adjustable resistor module is connected to the at least one resistor, the adjustable resistor unit is turned on.

5. The backlight module test circuit with adjustable current according to claim 1, wherein The test circuit for the backlight module with adjustable current includes: a toggle switch group; The adjustable resistor module is connected to the second end of the backlight module through the toggle switch group; The toggle switch group has at least one toggle switch unit; The toggle switch unit includes at least one second toggle switch; The toggle switch group is connected to the adjustable resistor module through the toggle end of the second toggle switch; When at least one toggle switch in each toggle switch unit is closed, the toggle switch group turns on the second end of the backlight module and the adjustable resistor module; At least one adjustable resistor unit in the adjustable resistor module can be conductively connected to the second end of the light module through the toggle switch group.

6. The adjustable current backlight module test circuit according to claim 5, wherein, Each adjustable resistor unit can be conductively connected to the second end of the light module through the toggle switch group.

7. The backlight module test circuit with adjustable current according to claim 6, characterized in that There are multiple of the toggle switch units; Multiple of the toggle switch units are connected in series. The toggle switch unit at the first end of the toggle switch group is connected to the second end of the backlight module, and the toggle switch unit at the second end of the toggle switch group is connected to the adjustable resistor module.

8. The backlight module test circuit with adjustable current according to claim 7, characterized in that The number of the second toggle switches of all the toggle switch units in the toggle switch group forms a geometric sequence, and the common ratio of the geometric sequence is the same as the number of channels of the second toggle switch.

9. The test circuit for an adjustable current backlight module according to any one of claims 1-8, characterized in that, The first end of the adjustable resistor module is connected to the ground terminal of the external regulated DC power supply; The second end of the adjustable resistor module is connected to the second end of the backlight module and the feedback voltage output terminal of the constant current power supply chip.

10. A backlight module testing system, characterized in that, Comprising: A backlight module; The test circuit for the backlight module with adjustable current according to any one of claims 1-9.

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