CN208208305U - A kind of backlight driving system and adjustable partial pressure protective module - Google Patents

Abstract

The utility model relates to backlight drive fields, and in particular to a kind of backlight driving system and adjustable partial pressure protective module.A kind of backlight driving system; including sequentially connected driving boost module, adjustable partial pressure protective module and backlight module; the adjustable partial pressure protective module includes that a resistance value adjusts circuit, and the resistance value adjusts the input voltage value that the sum of the maximum partial pressure value of circuit and the operating voltage value of backlight module are greater than driving boost module.The utility model between driving boost module and backlight module by being arranged adjustable partial pressure protective module; improve the output end voltage value of driving boost module; avoid the output end voltage value of driving boost module lower than the input terminal voltage value of driving boost module; to guarantee to boost, IC is worked normally; loss is reduced, testing efficiency is improved.

Description

A backlight drive system and adjustable voltage divider protection module

technical field

The utility model relates to the field of backlight driving, in particular to a backlight driving system and an adjustable voltage dividing protection module.

Background technique

In some common small-size display modules, due to the limitation of backlight size and cost, the number of LED lights allowed to be used is limited. In order to meet the brightness requirements of customers, backlight modules often use a scheme of connecting several single LED lights in parallel. For details, please refer to figure 1.

The normal driving voltage of commonly used LED lamps is 2.8-3.3V, and the current is 20mA; the driving voltage of a single lamp in parallel remains unchanged, so the total driving voltage VF=2.8-3.3V, and the current IF=20mA*number of LEDs. The DC/DC boost circuit is a common circuit used to drive the backlight module at present. It is built in the test fixture or the driver board. The DC/DC circuit is composed of a boost IC and peripheral circuits. The boost circuit works normally. The principle is to ensure that the output voltage Vout is greater than the input voltage Vin. For example, the input voltage Vin of a general step-up IC is 5V. To ensure that the circuit is normal, Vout>5V must be satisfied.

Therefore, when using this kind of fixture and driver board to test the backlight module with a single LED lamp connected in parallel, because Vout<5V, the boost IC does not work normally, and the phenomenon of burning out the fixture or backlight module often occurs, which is very serious. It greatly affects the efficiency and yield of the test.

Utility model content

The technical problem to be solved by the utility model is to provide a backlight driving system for the above-mentioned defects of the prior art, so as to avoid the burnout of the fixture or the backlight module.

The technical problem to be solved by the utility model is to provide an adjustable voltage divider protection module based on the backlight drive system to avoid burnout of the fixture or the backlight module in view of the above-mentioned defects of the prior art.

The technical solution adopted by the utility model to solve the technical problem is to provide a backlight drive system, including a drive boost module, an adjustable voltage divider protection module and a backlight module connected in sequence, and the adjustable divider voltage protection module includes a A resistance value adjustment circuit, the sum of the maximum divided voltage value of the resistance value adjustment circuit and the working voltage value of the backlight module is greater than the input voltage value of the drive booster module.

Among them, the preferred solution is: the resistance adjusting circuit includes a positive input terminal and a positive output terminal, and a fixed resistor and a rheostat arranged in parallel between the positive input terminal and the positive output terminal.

Among them, the preferred solution is: the backlight module includes multiple LED lamps arranged in parallel, the parallel input end is connected to the positive output end of the resistance adjustment circuit, and the parallel output end is connected to the negative input end of the resistance adjustment circuit.

Among them, the preferred solution is: the driving boost module includes a boost IC, and the boost IC inputs the boosted working current into the backlight module through the adjustable voltage dividing protection module.

Among them, a preferred solution is: the boost IC is a DC-DC boost IC.

Among them, a preferred solution is: the adjustable voltage division protection module and the drive boost module are integrally arranged on the same circuit board.

Among them, a preferred solution is: the backlight module and the driving and boosting module are integrally arranged on the same circuit board.

The technical solution adopted by the utility model to solve the technical problem is: provide an adjustable voltage divider protection module based on the backlight drive system, the backlight drive system includes a drive boost module and a backlight module, and the adjustable voltage divider protection module includes A resistance value adjustment circuit, the sum of the maximum divided voltage value of the resistance value adjustment circuit and the working voltage value of the backlight module is greater than the input voltage value of the drive booster module.

Among them, the preferred solution is: the resistance adjusting circuit includes a positive input terminal and a positive output terminal, and a fixed resistor and a rheostat arranged in parallel between the positive input terminal and the positive output terminal.

The beneficial effect of the utility model is that, compared with the prior art, the utility model improves the voltage value of the output terminal of the drive boost module by setting an adjustable voltage divider protection module between the drive boost module and the backlight module, and avoids driving The voltage value of the output terminal of the boost module is lower than the voltage value of the input terminal of the driving boost module, so as to ensure the normal operation of the boost IC, reduce loss, and improve test efficiency.

Description of drawings

The utility model will be further described below in conjunction with accompanying drawing and embodiment, in the accompanying drawing:

FIG. 1 is a schematic structural view of a backlight module in the prior art;

Fig. 2 is the structural representation of the utility model backlight driving system;

FIG. 3 is a schematic circuit diagram of the backlight driving system of the present invention.

Detailed ways

Now with reference to the accompanying drawings, the preferred embodiments of the present utility model are described in detail.

As shown in FIG. 2 and FIG. 3 , the utility model provides a preferred embodiment of a backlight driving system.

A backlight driving system, comprising a drive boost module 20, an adjustable voltage divider protection module 10 and a backlight module 30 connected in sequence, the adjustable voltage divider protection module 10 includes a resistance adjustment circuit, the resistance adjustment circuit The sum of the maximum divided voltage value and the working voltage value of the backlight module 30 is greater than the input voltage value of the driving boost module 20 .

Wherein, the driving boost module 20 boosts the input voltage, and supplies power to the backlight module 30 with the boosted electric energy to drive the backlight module 30 to work; The working voltage of the backlight module 30 with multiple LED lamps is often lower than the boosted voltage of the driving booster module. If the test fixture or the driver board is directly connected to the backlight module 30, it is easy to burn out the test fixture or the driver board.

And, by setting the divided voltage value through the adjustable voltage dividing protection module 10 , the output voltage value of the driving boost module 20 is increased to avoid burning out of the driving boost module 20 or the backlight module 30 . Preferably, the backlight current output by the driving boost module 20 passes through the adjustable voltage divider protection module 10 to generate a voltage, and then flows to the backlight module 30 to form a complete loop.

In this embodiment, referring to FIG. 3 , the resistance adjusting circuit includes a positive input terminal and a positive output terminal, and a fixed resistor and a rheostat arranged in parallel between the positive input terminal and the positive output terminal.

Specifically, the fixed resistor is R1, the variable resistor is R2, and the parallel resistance value R of the two is 1/{(1/R1)+(1/R2)}, that is, (R1R2)/(R1+R2). By adjusting the resistance value of the rheostat and adjusting the resistance value of the resistance adjusting circuit, the divided voltage value of the adjustable voltage dividing protection module 10 is further adjusted.

And, since the output current I1 of the driving boost module 20 remains unchanged, the value of the divided voltage V1 of the adjustable voltage dividing protection module 10 is I1*(R1R2)/(R1+R2), while the voltage value of the backlight module 30 is fixed The value V2, the input voltage value V3<V1+V2 of the drive booster module 20, can protect the backlight driving system, reduce fixture loss, and improve test efficiency.

In this embodiment, the backlight module 30 includes multiple LED lamps arranged in parallel, the parallel input end is connected to the positive output end of the resistance adjustment circuit, and the parallel output end is connected to the negative input end of the resistance adjustment circuit.

Wherein, the current I2 of the backlight module 30 is equal to the sum of the current I21 of each LED lamp.

In this embodiment, the driving and boosting module 20 includes a boosting IC, and the boosting IC inputs the boosted working current to the backlight module 30 through the adjustable voltage dividing protection module 10 .

Preferably, the boost IC is a DC-DC boost IC.

In this embodiment, the adjustable voltage divider protection module 10 and the drive boost module 20 are integrated on the same circuit board.

Alternatively, the backlight module 30 and the driving boost module 20 are integrally arranged on the same circuit board.

In the present utility model, a preferred embodiment of an adjustable voltage dividing protection module based on a backlight driving system is provided.

The backlight drive system includes a drive boost module and a backlight module, the adjustable voltage divider protection module includes a resistance adjustment circuit, the sum of the maximum divider voltage value of the resistance value adjustment circuit and the working voltage value of the backlight module is greater than the drive boost voltage The input voltage value of the module.

Preferably, the resistance adjustment circuit includes a positive input terminal and a positive output terminal, and a fixed resistor and a rheostat arranged in parallel between the positive input terminal and the positive output terminal.

The above are only the best embodiments of the utility model, and are not used to limit the scope of the utility model. All equivalent changes or modifications made according to the patent scope of the utility model are covered by the utility model.

Claims (9)

1. A backlight drive system, characterized in that: it includes a drive boost module, an adjustable voltage divider protection module and a backlight module connected in sequence, and the adjustable voltage divider protection module includes a resistance adjustment circuit, and the resistance value The sum of the maximum divided voltage value of the regulating circuit and the working voltage value of the backlight module is greater than the input voltage value of the driving boost module. 2. The backlight drive system according to claim 1, wherein the resistance adjusting circuit comprises a positive input terminal and a positive output terminal, and a fixed resistor arranged in parallel between the positive input terminal and the positive output terminal and rheostats. 3. The backlight driving system according to claim 2, wherein the backlight module comprises a plurality of LED lamps arranged in parallel, the parallel input end of which is connected to the positive output end of the resistance adjustment circuit, and the parallel output end of which is connected to The negative input terminal of the resistance adjustment circuit is connected. 4. The backlight driving system according to claim 3, wherein the driving boost module includes a boost IC, and the boost IC inputs the boosted operating current to the backlight via an adjustable voltage divider protection module module. 5. The backlight driving system according to claim 4, wherein the boost IC is a DC-DC boost IC. 6. The backlight driving system according to any one of claims 1 to 5, wherein the adjustable voltage division protection module and the driving boost module are integrated on the same circuit board. 7. The backlight driving system according to any one of claims 1 to 5, wherein the backlight module and the driving and boosting module are integrated on the same circuit board. 8. An adjustable voltage divider protection module based on a backlight drive system, the backlight drive system includes a drive boost module and a backlight module, it is characterized in that: the adjustable voltage divider protection module includes a resistance value adjustment circuit, and the resistance value The sum of the maximum divided voltage value of the regulating circuit and the working voltage value of the backlight module is greater than the input voltage value of the driving boost module. 9. The adjustable voltage divider protection module according to claim 8, characterized in that: the resistance adjustment circuit includes a positive input terminal and a positive output terminal, and is arranged between the positive input terminal and the positive output terminal and arranged in parallel fixed resistors and rheostats.