KR102101422B1 - Low power display board with surplus voltage control - Google Patents

Abstract

The present invention relates to a low-power electronic display board using surplus voltage control. The low-power electronic display board using surplus voltage control consists of a plurality of LED chips with anode and cathode electrodes arranged on an upper portion of a non-conductive substrate, and comprises: three red chips wire-bonded in series; two green chips wire-bonded in series; and two blue chips wire-bonded in series. Each of the red chips, green chips, and blue chips is constructed in an SMD top-type package with six leads to include an LED module to supply positive (+) power and negative (-) power for each color through each lead. According to the present invention, surplus voltage is controlled to lower power consumption to reduce energy. An arrangement of a plurality of series chips increases input DC voltage, lowers applied current, and increases DC applied voltage to allow power reduction by an increase in SMPS AC converting efficiency. Power applying wiring from the SMPS to modules is simplified to reduce wiring costs. Power consumed by heating is lowered to minimize degradation of LED and IC devices sensitive to heat to increase expected life and durability, simplify circuitry, and reduce the number of components used to reduce malfunction probabilities and reduce manufacturing costs.

Description

LOW POWER DISPLAY BOARD WITH SURPLUS VOLTAGE CONTROL through surplus voltage control

The present invention relates to a low-power electronic display board by controlling the excess voltage. More specifically, the input DC voltage to the LED is increased and the input current is lowered through a plurality of serial chip arrangements to reduce power consumption through increasing SMPS AC converting efficiency. It is related to the technology of reducing and simplifying the wiring of power applied from the SMPS to the module to reduce the wiring cost.

LED (Light Emitting Diode) refers to a light emitting diode that is a semiconductor device that emits light, and emits light of various colors such as red, green, and blue, and is used as an electronic display panel for various electronic products and instrument panels. The LED module, in which a plurality of LED packages are packaged in one, is mounted on a case by combining a tiled LED module, SMPS, and control controller, and the LED display (LED Display) that displays images through individual flashing control of each LED package. Board).

The LED package constituting the conventional LED module used an epoxy molded lamp type having a DIP type lead. Therefore, each of the three primary colors, R, G, and B, which are required for full color realization, are composed of independent packages for each color, so that multiple LED packages are installed to form one full color pixel. This DIP type LED package has a problem in manufacturing a high-resolution LED module for a high-resolution display board having a large number of LED chips and a narrow pixel spacing due to the need for a perforated PCB board. For this reason, a 3 in 1 SMD LED package with all three colors of LED chips mounted on a SMD type LED package that was used only indoors began to be used as an outdoor billboard.

As described above, while using a 3 in 1 SMD LED package for outdoor use, it was possible to realize high-resolution outdoor billboards, and the SMT soldering method made it possible to manufacture outdoor LED modules with increased reliability compared to existing DIP type soldering. Here, for outdoor use, the product is made of silicon molded LED lead part exposed on the front surface for the purpose of waterproofing, and rubber-packed the LED module and the housing case coupling part. It is also used in Edo. For this reason, it is correct to call it a waterproof type, but it is popularly referred to for outdoor use.

However, the disadvantage of the SMD LED package is that, unlike the DIP LED package with a convex lens, the planar lens has a wider viewing angle. Generally, DIP LED package has an Oval type lens for use in electronic displays, so it has a light directing angle of about 100 to 120 degrees left and right and 40 to 50 degrees up and down. However, the SMD LED package is difficult to mount a dome type lens, and is manufactured in a flat lens shape, and has a wide directivity of 100 to 120 degrees.

The signboard made with the SMD LED package with the wider viewing angle has the advantage of showing good visibility at a wider angle than the signboard made with the DIP LED package, but more power is required to maintain more than a certain brightness due to the decrease in front luminance. There is also a disadvantage that consumption of.

In other words, the total amount of the displayed light is the same as the DIP LED package and the SMD LED package, but there is a problem in that the luminance difference of the front part occurs depending on the directivity angle.

Specifically, the 3 in 1 SMD LED package is composed of one LED chip each for R, G, and B, and the voltage of each LED chip for R, G, and B is 2V, 3V, and 3V, respectively. These LED packages are arranged in 16x16 or 32x16 pixels to form one LED module, which supplies 5V DC or less voltage to the LED module, and controls the voltage supply through a constant current IC.

At this time, when using 5V voltage, each LED chip of R, G, B is supplied with 2V, 3V, 3V by constant current IC, and the excess voltage of 3V, 2V, 2V, which is the difference from the applied voltage, is wasted as heat in the constant current IC. .

In addition, the heat generated in this way adversely affects the reliability (life and durability) of the product, and causes unnecessary power wasting by operating a cooling device for reducing the generated heat.

Recently, a configuration has been disclosed in which the applied voltage is reduced from 5V to 4V and the heat generated in the constant current IC is lowered to restore the reliability of the LED module and prevent power waste.

However, in SMPS AC-DC converting, output conversion efficiency is not high in products with output voltage of 7.5V or less (9V depending on the product) (5V, 4V, 3V, etc.). Since the heat generated by the constant current IC is generated in the SMPS instead, there is no great power gain in the whole sign board.

In addition, when the voltage is reduced from 5V to 4V, the wiring from SMPS to the LED module requires shorter and thicker wires to prevent a voltage drop, which increases the cost of wiring and thus has no economic benefit.

Republic of Korea Patent Publication No. 10-2015-0013421 (published on February 5, 2015)

An object of the present invention for solving and overcoming the above-mentioned problems is a problem of a decrease in front luminance or an increase in power use in the case of the same luminance when manufacturing an LED using a SMD LED package, and a surplus generated in a module circuit in manufacturing the LED LED In order to prevent the heat generated by the voltage and the resulting decrease in the overall durability of the LED and the billboard, the efficiency of the module using the SMD LED package is increased to reduce the power consumption in the implementation of the high brightness of the outdoor billboard.

Another object of the present invention is to minimize the difference between the DC voltage supplied through the SMPS and the applied voltage of the LED to reduce the heat generated by the voltage difference, thereby increasing durability and additional power consumption consumed for cooling. It is to save.

In addition, it is generally necessary to mount the resistor due to the high voltage difference between the DC voltage supplied to the LED module and the red LED chip, which causes high temperature in the constant current IC for red LED control. Since it is possible to remove the resistor by constructing, it is possible to dissipate the high heat generated in the constant current IC and to simplify the circuit configuration to reduce the product failure rate and reduce manufacturing cost.

One embodiment of the present invention for achieving such a technical problem is a low-power electronic board through the control of the surplus voltage, each of the Anode and Cathode electrodes is composed of a plurality of LED chips provided on the non-conductive substrate, wire-bonded in series 3 Red chips; Two green chips wire-bonded in series; And two blue chips wire-bonded in series; but each of the red chip, green chip, and blue chip is composed of a SMD TOP type package with six leads, for each color of the red chip, green chip, and blue chip. And an LED module that supplies + and-power through the lead.

Preferably, the LED module is characterized in that it is supplied with SMPS power outputting a voltage of 6V to 9V or less (preferably 7V to 7.5V).

In addition, the LED module is characterized in that it prevents overheating through heat dissipation by excluding the resistor mounted on the output wiring of the red chip control constant current IC.

In addition, the LED module includes a voltage regulator or a DC converter that supplies a 3.3V to 5V voltage to a decoder IC, a transceiver IC, and a constant current IC provided therein by dropping the voltage of the supplied 7V to 3.3V to 5V. Is done.

In addition, it is characterized in that it further comprises a decoder IC, a transceiver IC provided in the LED module, and a controller for supplying a voltage of 3.3V to 5V with a constant current IC.

In addition, the LED module is characterized in that it is controlled by sequentially lighting through a wiring perpendicular to the FET output to 7V to control each of a plurality of red chips, green chips, and blue chips with one control line of a constant current IC.

According to the present invention as described above, by controlling the surplus voltage to lower the power consumption, there is an effect of saving energy.

According to the present invention, the input DC voltage is increased, the applied current is lowered, and the DC applied voltage is increased by a plurality of serial chip arrangements, thereby reducing power by increasing SMPS AC converting efficiency, and applying power from SMPS to the module. This simplifies the effect of reducing wiring costs.

According to the present invention, there is an effect of increasing life expectancy and durability by lowering power consumed by heat generation to minimize deterioration of heat-sensitive LED and IC devices.

According to the present invention, by simplifying the circuit and reducing the number of parts used, there is an effect of reducing the probability of failure and reducing the manufacturing cost.

1 is a block diagram schematically showing a low-power scoreboard through control of a surplus voltage according to an embodiment of the present invention.
Figure 2 is an exemplary view showing a red chip, a green chip and a blue chip provided in the LED package of the low power electronic board through the control of the surplus voltage according to an embodiment of the present invention.
Figure 3 is an exemplary view showing a specification of a product commonly used in electronic displays.
FIG. 4 is a block diagram showing that a low-power electronic board through a surplus voltage control according to an embodiment of the present invention includes a voltage regulator or a DC converter.
Figure 5 is a block diagram showing that the low-power electronic board through the control of the surplus voltage according to an embodiment of the present invention is controlled by the controller.
6 is a circuit diagram showing a typical 1/2 Duty dynamic control module.
7 is a circuit diagram illustrating a 1/2 duty module in which a noise removal circuit is added to remove noise from the dynamic control module.
8 is a view showing a fine lighting situation of a paired LED in a typical 1/2 duty module circuit.
9 is a view showing that the problem of fine lighting of a paired LED in a 1/2 Duty module to which a noise removal circuit is added is solved.
FIG. 10 is a circuit diagram of a noise removal circuit in which a minute lighting problem is solved for a paired LED of 1/2 duty of a low-power electronic display board by controlling a surplus voltage according to an embodiment of the present invention.

The specific features and advantages of the present invention will become more apparent from the following detailed description based on the accompanying drawings. Prior to this, the terms or words used in the specification and claims are based on the principle that the inventor can appropriately define the concept of terms in order to best describe his or her invention in the technical spirit of the present invention. It should be interpreted as a matching meaning and concept. In addition, it should be noted that when it is determined that the detailed description of the known functions and configurations related to the present invention may unnecessarily obscure the subject matter of the present invention, the detailed description is omitted.

Referring to Figure 1, the low-power electronic board (B) through the surplus voltage control according to an embodiment of the present invention, each of the Anode and Cathode electrode is composed of a plurality of LED chips provided on the non-conductive substrate, wire bonding in series 7 red LEDs (102), two green chips (104) wire-bonded in series, and two blue chips (106) wire-bonded in series. It consists of a package, and is configured to include an LED module 100 that supplies + and -power for each color through each lead.

The LED module 100 according to the above-described configuration can minimize power loss and suppress heat generation by minimizing power lost in a difference between a supply voltage and an applied voltage of the LED.

Specifically, the LED package is composed of three red chips (2V x 3ea = 6V), two green chips (3V x 2ea = 6V), and two blue chips (3V x 2ea = 6V). That is, it consists of an LED package in which three Red chips 102 are connected in series, two Green chips 104 are connected in series, and two Blue chips 106 are connected in series. The voltage is set to 6V. At this time, there may be a slight voltage deviation according to each chip rank due to differences in production timing, specifications, and suppliers.

In general, the green chip 104 and the blue chip 106 of the LED package is used by cutting a wafer grown on a sapphire substrate. At this time, the sapphire substrate has two electrodes on the upper side by cutting the upper portion of the epi and supplying the lower electrode to supply + and-power to the non-conductive substrate. In this way, when two chips are connected in series, bonding is possible directly to the chip and the chip.

However, the universal red chip 102 is grown on a conductive GaAs substrate to be fabricated as a chip, or replaced with a conductive silicon or GaP substrate for the purpose of increasing light intensity to be fabricated as a chip.

Therefore, when an electrode is formed at the bottom of the chip and connected in series, the leadframe portion to which the chip is attached must be separated, which is difficult due to various utilization of the leadframe and the space of the SMD package, which is not desirable.

Therefore, the low-power electronic board (B) through the surplus voltage control according to an embodiment of the present invention, three red chips 102 are configured in series (two bonding from chip to lead, and two bonding from chip to chip) ), And the Green chip 104 and Blue chip 106 are serially composed of 2 chips (processed as 2 bondings from chip to lead and 1 bonding from chip to chip), and RGB 7chips in and around 6V with similar voltage It provides an LED module 100 composed of a 1 SMD LED package.

As shown in FIG. 2, the number of red chips 102, green chips 104, and blue chips 106 provided in the LED package according to an embodiment of the present invention is 3, respectively, as described above. It is composed of two and two identically, but the position of the chip for each color can be changed.

For example, the red chip 102, the green chip 104, and the blue chip 106 are arranged in order from the left, but the blue chip 106, the green chip 104, and the red chip 102 or the green chip 104 are arranged. , Blue chip 106 and Red chip 102, etc. may be arranged.

In addition, since there are no electrodes at the bottom, LED chips that are currently focused on the top may be placed in different positions, and the shape of forming + and-electrodes for each color on the six external electrodes must be maintained, or + or -The electrodes can be grouped into one electrode and composed of four electrodes.

As described above, according to the above-described configuration, the applied voltage of each of the red chip 102, the green chip 104, and the blue chip 106 has 6V to 6.5V, and thus, SMPS of about 7V to 7.5V is applied. It is possible to drive the lighting in a low heating state with a voltage.

Here, as shown in FIG. 2, the red chip 102 transfers the grown semiconductor light-emitting structure from the growth substrate, and bonds it to the sapphire substrate as a support substrate (the bonding layer is not shown in FIG. 2), so that the sapphire substrate The height of the entire red chip 102, including, may be similar to the overall height of the green chip 104 or blue chip 106 including the sapphire substrate, which is a growth substrate, and the height of the red chip 102 and the green chip ( 104) or the difference between the height of the blue chip 106 may be 20% or less of the height of the red chip 102. This makes it possible to improve the uniformity of the light emission angle according to the inclination of the lead frame cups of the R, G, and B chips by configuring the heights of the red chips 102, green chips 104, and blue chips 106 to be similar to each other. Which has a remarkable effect.

Hereinafter, the structural features of the low power electronic display board B through the control of the surplus voltage according to an embodiment of the present invention are as follows.

3 is a diagram showing a specification of a product commonly used in a signboard, and power is supplied from a single SMPS to a plurality of LED modules. In general, in the case of an LED module using a low voltage of 5V, the length of wiring becomes long or thin wire When using, there is a problem that the voltage drop occurs, and thus, the image is not properly implemented.

On the other hand, the low-power electronic board (B) through the surplus voltage control according to an embodiment of the present invention, by supplying the voltage converted to 7V or more to the LED module 100, the power conversion efficiency than the conventional conversion to 5V is very (5% or more) becomes high, and wiring cost can be reduced.

In addition, the LED module 100 according to an embodiment of the present invention is configured by excluding the resistor mounted on the output wiring of the constant current IC for controlling the red chip 102 to prevent overheating through heat dissipation, the red chip Blocking heat transmitted to (102), it is possible to prevent the occurrence of module errors by increasing the number of contact points.

On the other hand, the control signal input portion of the decoder IC, the transceiver IC, and the constant current IC provided in the LED module 100 requires a voltage of 3.3V to 5V in order to perform data communication and processing between the module and the module.

Accordingly, the LED module 100 according to an embodiment of the present invention, as shown in FIG. 4, the DC voltage before and after the 7V is applied to the LED module 100 is dropped to 5V decoder decoder, transceiver IC and constant current It comprises a voltage regulator 108 or a DC converter 110 for supplying a 3.3V to 5V voltage to the IC.

At this time, since the power required by each of the decoder IC and the transceiver IC and the constant current IC provided inside the LED module 100 is very small, it is configured by simply adding one voltage regulator 108 considering the price and the size of the components. It is desirable to do.

Or, as shown in Figure 5, the low-power electronic display board (B) through the surplus voltage control according to an embodiment of the present invention, without using a separate voltage regulator 108 or DC converter 110, the controller 200 ) May be configured to supply 3.3V to 5V voltage to a decoder IC, a transceiver IC, and a constant current IC provided in the LED module 100 using some lines of a data cable connecting the LED module 100.

Hereinafter, the configuration of the dynamic module of the low-power electronic display board B through the control of the excess voltage according to an embodiment of the present invention will be described below with respect to noise caused by high voltage application and resulting residual image removal.

If a typical LED module assumes a matrix having an array of 16 × 16 as a module, and the size of the LED module is specified as 300 mm, a pitch spacing of 18.75 mm per pixel is obtained due to 16 horizontal arrays and 16 vertical arrays. .

One pixel is composed of a red chip (102), a green chip (104) and a blue chip (106) for full color, and one LED module (100) is composed of 16 × 16 = 256 pixels and a red chip (102). , When one pixel is composed of three chips of the green chip 104 and the blue chip 106, a total of 256 × 3 = 768 chips.

In this case, when a current of 20mA is applied to each of the red chip 102, the green chip 104, and the blue chip 106, a total of 15.26A of current is applied to the LED module 100, and calculated by applying 5V voltage to 76.3 When the amount of power of W comes out, and the current consumed by the IC driving the circuit is included, 80 W of power is finally applied.

In the case of a real product, since the power consumption of about 70W when the outdoor luminance standard for a 300mm size LED module is 10,000nit, it can be compared as shown in [Table 1] below.

[Table 1]

At this time, the power consumption of the LED chips connected in series is calculated by driving mode × supply voltage × current per chip × number of chips. In conclusion, the efficiency of 27% increases in power consumption when using high voltage. (About 30% increase in actual product measurement)

Referring to [Table 1] above, the driving mode and current per LED chip are as follows. The largest standard among LED modules is 300mm. Therefore, smaller sized products are manufactured with lower applied current when making 10,000nit luminance products. Therefore, instead of using a lower current, a constant current IC is controlled by sequentially lighting through a wiring orthogonal to the FET to control two LED modules, four LED modules, or more LED modules with one control line.

When 1: 1 control of the LED module is referred to as static control, and 1: N control of the LED module is referred to as dynamic control, the LED module classifies the product at 20mA, so that the entire scoreboard is made of pixels of the same color and brightness. In order to configure, it is advantageous to control the current value closest to the LED rank classification.

According to the [Table 1], when controlled by a 7 in 1 LED, the applied current per LED chip is very low, about 10 mA, so it is appropriate to design it to be turned on with a reference current by actually lighting at 1/2 Duty.

6 is a circuit diagram showing a general 1/2 Duty module, and FIG. 7 is a circuit diagram showing a 1/2 Duty module to which a noise removal circuit is added for noise removal.

According to this driving, it is possible to replace a static LED module that needs to be controlled using 48 constant current ICs that generally control 16 pixels with a dynamic LED module that requires only 24 ICs.

According to this configuration, there is an effect of reducing the failure rate by reducing the cost of the LED module and reducing the number of parts, and 1/2 duty products are 1/4 duty and 1/4 duty products are usually 1/8 duty. can do.

As shown in FIG. 8, in the case of a 1/2 duty module, two LED chips are paired to light sequentially by a FET. (1/4 duty is 4 LEDs) When 1 LED chip is turned on, Pair Another LED chip may be finely lit.

9 is a view showing that the problem of fine lighting of a paired LED chip in a 1/2 Duty module to which a noise removal circuit is added, and FIG. 10 is low power through control of a surplus voltage according to an embodiment of the present invention This is a noise removal circuit that solves the problem of minute lighting of the LED chip paired at 1/2 duty of the electric sign (B).

As described above, according to an embodiment of the present invention, noise is generated in a signal output from the FET due to a difference between a 5V signal output from the existing decoder IC and a 7V voltage applied to the FET. Because of this, the voltage of the signal output from the decoder IC can be replaced with 7V to remove noise from the FET output signal.

Meanwhile, [Table 2] shows the LED module 100 of the low-power electronic display board B through redundancy voltage control according to an embodiment of the present invention, that is, three red chips 102 and two green chips 104, respectively. This table compares the electrical characteristics and efficiency of the LED module 100 packaged in 7 in 1 with the Blue chip 106 and the conventional 3 in 1 packaged LED module.

[Table 2]

As shown in Table 2, according to an embodiment of the present invention, the 7 in 1 packaged LED module 100 can reduce power consumption (based on DC) by 37% compared to the conventional 3 in 1 packaged LED module. , As a result, it is possible to improve the luminous efficiency and reduce the heat generation, and it can be seen that the performance and reliability of the LED module and the display device employing this are significantly increased.

And, [Table 3] is a table comparing the advantages, disadvantages, and efficiency of the LED module of the registered patent No. 10-1651923 and the LED module according to an embodiment of the present invention.

[Table 3]

As can be seen from [Table 3], the conventional R chip, G chip, and B chip are each composed of one, but the Red chip 102, Green chip 104 and Blue chip (106) according to an embodiment of the present invention ) Consists of 3, 2 and 2 respectively. In addition, the conventional R chip, G chip, B chip is applied with a voltage of 6V, respectively, but the applied voltage according to an embodiment of the present invention is Red chip 102, Green chip 104 and Blue chip 106. It is configured to apply 2V, 3V and 3V, respectively.

Conventionally, as it is developed as an epi-stack stack type to implement 6V voltage, it can be applied to small LED modules because only 3 chips (R chip, G chip, and B chip) are used, but vertical stacking causes light loss. , There is a problem that the product price is high.

On the other hand, according to an embodiment of the present invention, as the mass-production type chip is serially bonded to the LED module to implement 6V voltage, the surface area of the chip increases as a whole due to the arrangement of multiple chips, resulting in an increased amount of extraction light and the use of a mass-production type chip. As a result, product uniformity is increased by using only a few rank chips, and chip supply and demand and LED production are easy.

In summary, according to an embodiment of the present invention, it is possible to apply a high voltage to the LED module and the display device, and accordingly, in selecting the wiring supplied from SMPS to each LED module, considering the voltage drop, compared with the short and thick conventional wiring Relatively longer and thinner wiring is possible, which increases the freedom of design.

In addition, in the PCB design for driving the LED module, a low current according to a high voltage is possible, so that the wiring pattern in the PCB can be thinly designed, and the integration of the wiring patterns in the PCB is improved, thereby reducing PCB usage and simplifying.

As described above, the present invention has been described and illustrated in connection with a preferred embodiment for illustrating the technical idea of the present invention, but the present invention is not limited to the configuration and operation as illustrated and described, and deviates from the scope of the technical idea. It will be understood by those skilled in the art that many changes and modifications to the present invention are possible without. Accordingly, all such suitable changes and modifications and equivalents should be considered to be within the scope of the present invention.

B: Low-power electronic display board through surplus voltage control
100: LED module
102: Red chip
104: Green chip
106: Blue chip
108: voltage regulator
110: DC converter
200: controller

Claims (6)

In the low-power scoreboard through the control of the surplus voltage comprising a plurality of LED modules,
Each of the anode and cathode electrodes constitutes an LED package with a plurality of LED chips provided on a non-conductive substrate,
A plurality of the LED package,
Three red chips wire-bonded in series,
Two green chips wire-bonded in series,
It consists of two blue chips wire-bonded in series.
The applied voltages of the three red chips, the two green chips, and the two blue chips are composed of 6V to 6.5V, respectively.
The LED package is composed of an SMD TOP type package having 6 leads so that + and-power can be supplied to each of the Red chip, Green chip, and Blue chip,
Arrange a plurality of the LED package to configure the LED module,
The LED module, the low-power electronic display board through the control of the surplus voltage, characterized in that receiving the SMPS power outputting a voltage of 7V to 7.5V. delete According to claim 1,
The LED module,
Low-power electronic display board through the control of the surplus voltage, characterized in that it is configured to exclude the resistor mounted on the output wiring of the red chip control constant current IC. According to claim 1,
Among the LED modules, the module controlled by the dynamic method,
It includes a voltage regulator or a DC converter for dropping the supplied voltage of 7V to 7.5V to 3.3V to 5V to supply 3.3V to 5V voltage to a decoder IC, a transceiver IC, and a constant current IC provided therein.
A low-power electronic display board with a surplus voltage control, characterized in that it has a noise removal circuit to replace the signal output from the decoder IC with a voltage level of 3.3 to 5V to 7V. delete According to claim 1,
The LED module,
Low power through surplus voltage control, characterized in that it is controlled by a sequential lighting method through a wiring perpendicular to the FET output to 7V to control each of a plurality of red chips, green chips, and blue chips with one control line of a constant current IC Billboard.

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