KR100678774B1 - Driving device and driving method of light emitting diode array module - Google Patents

Abstract

The present invention relates to a driving device and a driving method of a light emitting diode array module capable of reducing heat generation of a transistor for emitting a red light emitting diode.

A driving device of the LED array module according to the present invention includes a driving voltage source for supplying a driving voltage; A voltage drop unit connected to the driving voltage source; A red LED array connected in series with the voltage drop; A green LED array connected in series with said driving voltage source; A blue LED array connected in series with said driving voltage source; A first transistor connected between said red LED array and a ground voltage source; A second transistor connected between the green LED array and the base voltage source; A third transistor connected between the blue LED array and the base voltage source; And a control unit for controlling each of the first to third transistors.

According to this configuration, the present invention can minimize the heat generation of the transistor for emitting the red light emitting diode by dropping and supplying the driving voltage supplied to the red light emitting diode array of the red, green and blue light emitting diode array using the voltage drop. have. Therefore, the present invention can minimize the heat generation of the transistor for emitting the red light emitting diode to reduce the size and cost of the light emitting diode array module.

Description

Driving apparatus and driving method of light emitting diode array module {APPARATUS AND METHOD FOR DRIVING OF LIGHT EMITTING DIODE ARRAY MODULE}

1 is a view schematically showing a conventional LED array driving apparatus.

2 is a graph showing the voltage-current characteristics of red, green and blue LEDs.

3 is a view showing a driving device of the LED array module according to an embodiment of the present invention.

4 is a circuit diagram illustrating a voltage drop unit according to a first embodiment of the present invention illustrated in FIG. 3.

FIG. 5 is a circuit diagram illustrating a voltage drop unit according to a second embodiment of the present invention illustrated in FIG. 3.

<Description of Symbols for Main Parts of Drawings>

100: voltage drop 110: red LED array

120: green LED array 130: blue LED array

140: control unit

The present invention relates to a driving device and a driving method of a light emitting diode array module, and more particularly, to a driving device and a driving method of a light emitting diode array module capable of reducing the heat generation of a transistor for emitting a red light emitting diode.

In general, a light emitting diode (LED) is formed by bonding a P-type semiconductor and an N-type semiconductor and then applying a forward current to recombine holes and electrons in the bonding layer to stabilize the recombination generated at this time. Light is generated by energy.

Such LEDs include a blue LED using a blue phosphor (GaN-based), a green LED using a green phosphor (InGaN-based), and a red LED using a red phosphor (GaAs-based).

A plurality of such LEDs are arranged in a predetermined size to be called an LED array. LEDs are used in advertising displays, backlights of liquid crystal displays, lighting lamps, mood lights, building lighting devices, bridge lighting devices, and various decorative lights.

1 is a view schematically showing a conventional LED array driving apparatus.

Referring to FIG. 1, a conventional LED array driving apparatus includes a red LED array 10 connected in series to a driving voltage source VCC, a green LED array 20 connected in series to a driving voltage source VCC, and a driving voltage source VCC. A blue LED array 30 connected in series, a first transistor Q1 connected between the red LED array 10 and the ground voltage source GND, and a second connected between the green LED array 20 and the ground voltage source GND. A control unit 40 for controlling each of the third transistor Q3 and the first to third transistors Q1, Q2, and Q3 connected between the transistor Q2, the blue LED array 30, and the base voltage source GND is provided. Equipped.

The red LED array 10 includes first to fifth red connected in series between the first resistor R1 connected to the driving voltage source VCC and the collector terminal of the first resistor R1 and the first transistor Q1. LEDs R_LED1 to R_LED5 are provided.

The first resistor R1 is a bias resistor for keeping the current supplied to the first to fifth red LEDs R_LED1 to R_LED5 constant.

Each of the first to fifth red LEDs R_LED1 to R_LED5 is connected in series in the forward direction between the first resistor R1 and the collector terminal of the first transistor Q1.

The green LED array 20 includes first to fifth greens connected in series between a second resistor R2 connected to the driving voltage source VCC and a collector terminal of the second resistor R2 and the second transistor Q2. LEDs G_LED1 to G_LED5 are provided.

The second resistor R2 is a bias resistor for keeping the current supplied to the first to fifth green LEDs G_LED1 to G_LED5 constant.

Each of the first to fifth green LEDs G_LED1 to G_LED5 is connected in series in the forward direction between the second resistor R2 and the collector terminal of the second transistor Q2.

The blue LED array 30 includes first to fifth blue connected in series between the third resistor R3 connected to the driving voltage source VCC and the collector terminal of the third resistor R3 and the third transistor Q3. LEDs B_LED1 to B_LED5 are provided.

The third resistor R3 is a bias resistor for keeping the current supplied to the first to fifth blue LEDs B_LED1 to B_LED5 constant.

Each of the first to fifth blue LEDs B_LED1 to B_LED5 is connected in series in the forward direction between the third resistor R3 and the collector terminal of the third transistor Q3.

The controller 40 generates the red, green, and blue control signals R_CS, G_CS, and B_CS to independently or commonly emit the red, green, and blue LED arrays 10, 20, and 30 so as to generate the first to third times. The transistors Q1, Q2 and Q3 are respectively controlled.

The first transistor Q1 is a collector electrically connected to the base terminal to which the red control signal R_CS from the controller 40 is supplied through the fourth resistor R4, and to the cathode electrode of the fifth red LED R_LED5. An emitter terminal connected to the terminal and the ground voltage source (GND). The first transistor Q1 is turned on according to the red control signal R_CS to connect the red LED array 10 to the ground voltage source GND to emit light.

The second transistor Q2 is a collector electrically connected to the base terminal to which the green control signal G_CS is supplied from the controller 40 through the fifth resistor R5 and to the cathode electrode of the fifth green LED G_LED5. An emitter terminal connected to the terminal and the ground voltage source (GND). The second transistor Q2 is turned on according to the green control signal G_CS to connect the green LED array 20 to the ground voltage source GND to emit light.

The third transistor Q3 is a collector electrically connected to the base terminal to which the blue control signal B_CS from the control unit 40 is supplied through the sixth resistor R6, and to the cathode electrode of the fifth blue LED B_LED5. It has an emitter terminal connected to the terminal and the ground voltage source (GND). The third transistor Q3 is turned on according to the blue control signal B_CS to connect the blue LED array 30 to the ground voltage source GND to emit light.

The driving method of the LED array using the conventional LED array driving apparatus is as follows.

First, the controller 40 generates red, green, and blue control signals R_CS, G_CS, and B_CS to independently and / or commonly emit the red, green, and blue LED arrays 10, 20, and 30. Here, when the red, green, and blue LED arrays 10, 20, and 30 emit light in common, the controller 40 generates red, green, and blue control signals R_CS, G_CS, and B_CS in a high state.

The red, green, and blue control signals R_CS, G_CS, and B_CS of the high state generated by the controller 40 are supplied to the base terminals of the first to third transistors Q1, Q2, and Q3, thereby providing the first to third. Transistors Q1, Q2 and Q3 are turned on.

As the first to third transistors Q1, Q2, and Q3 are turned on, the driving current from the driving voltage source VCC is supplied to the red, green, and blue LED arrays 10, 20, and 30, thereby providing red, green, and Generate red, green and blue light from each of the blue LED arrays 10, 20, 30.

Meanwhile, each of the red, green, and blue LED arrays 10, 20, and 30 may emit light sequentially or randomly according to a control signal from the controller 40.

Among these red, green and blue LEDs, the green and blue LEDs have a similar operating voltage Vf as shown in FIG. 2, while the red LEDs have a relatively low operating voltage Vf.

Accordingly, since the operating voltages of the red, green, and blue LEDs are different from each other, the red LEDs emitted by the operating voltages lower than the second and third transistors Q2 and Q3 emitting the green and blue LEDs emit light. Much heat is generated in the first transistor Q1.

The power consumption P of the first to third transistors Q1, Q2, and Q3 is shown in Table 1 below.]

Q1 Q2 Q3 Driving voltage (VCC) 24V 24V 24V Drive Current (If) 0.35A 0.35A 0.35A Operating voltage (Vf) 2 V 3.5 V 3.5 V Quantity (ea) 5ea 5ea 5ea Power Consumption (P = VCC- (Vf * Quantity) * If) 4.9 W 2.27 W 2.27 W

Therefore, the driving device and driving method of the conventional LED array module has a relatively high power consumption (P) of the red LED array 10 by the relatively low operating voltage, the power consumption increases as the LED is high brightness red LED There is a problem that more heat is generated in the first transistor Q1 emitting light.

On the other hand, the driving device and the driving method of the conventional LED array module is a large amount of heat generated in the first transistor (Q1), so additional heat sink for heat dissipation is necessary, so the size of the LED array module due to the area of the heat sink And cost increases.

Accordingly, an object of the present invention is to provide a driving device and a driving method of a light emitting diode array module capable of reducing heat generation of a transistor for emitting a red light emitting diode.

In addition, another object of the present invention is to provide a driving apparatus and a driving method of a light emitting diode array module which can reduce the heat generation of the transistor for emitting a red light emitting diode to reduce the size and cost of the light emitting diode array.

In order to achieve the above object, the driving device of the LED array module according to an embodiment of the present invention includes a driving voltage source for supplying a driving voltage;

A voltage drop unit including a first resistor R1 connected to the driving voltage source and one or more diodes connected in series with the first resistor R1 to reduce a driving voltage; and a red LED array connected in series with the voltage drop unit Wow;

A second LED (R2) connected to the driving voltage source and a green LED array connected in series to the second resistor (R2);

A blue LED array connected in series with a third resistor (R3) connected to the driving voltage source and the third resistor (R3);

A first transistor connected between said red LED array and a ground voltage source;

A second transistor connected between said green LED array and said base voltage source;

A third transistor connected between the blue LED array and the base voltage source;

And a control unit for controlling each of the first to third transistors.

A method of driving a light emitting diode array module according to an embodiment of the present invention includes supplying a driving voltage to a voltage drop including one or more diodes connected in series through a first resistor to reduce the driving voltage to generate a falling voltage; ;

Supplying the drop voltage to a series of red LED arrays connected in series;

Supplying the drive voltage to a green LED array connected in series through a second resistor;

Supplying the drive voltage to a blue LED array connected in series through a third resistor;

Switching the first transistor connected between the red LED array and the base voltage source, the second transistor connected between the green LED array and the base voltage source, and the third transistor connected between the blue LED array and the base voltage source, Emitting at least one of the first to third color LED arrays.

Other objects and features of the present invention in addition to the above objects will be apparent from the description of the embodiments with reference to the accompanying drawings.

Hereinafter, a driving apparatus and a driving method of the LED array module according to the preferred embodiment of the present invention will be described.

3 is a view showing an LED array driving apparatus according to an embodiment of the present invention.

Referring to FIG. 3, the LED array driving apparatus according to the exemplary embodiment of the present invention includes a voltage drop unit 100 connected to a driving voltage source VCC through a first resistor R1, and a red connected in series to the voltage drop unit 100. LED array 110, green LED array 120 connected in series via a second resistor R2 to a driving voltage source VCC, blue LED array 120 connected in series through a third resistor R3 to a driving voltage source VCC, The first transistor Q1 connected between the red LED array 110 and the ground voltage source GND, the second transistor Q2 connected between the green LED array 120 and the ground voltage source GND, and the blue LED array 130. And a control unit 140 for controlling each of the third transistor Q3 and the first to third transistors Q1, Q2, and Q3 connected between and the ground voltage source GND.

The voltage drop unit 100 reduces the driving voltage from the driving voltage source VCC to supply the drop voltage to the red LED array 110.

To this end, the voltage drop unit 100 may include first to n-th diodes connected in series between the first resistor R1 connected to the driving voltage source VCC and the red LED array 110, as shown in FIG. 4. D1 to Dn).

The first resistor R1 is a bias resistor for making the current supplied to the first to nth diodes D1 to Dn constant.

The first to n th diodes D1 to Dn are connected in series between the first resistor R1 and the red LED array 110.

The first to nth diodes D1 to Dn drop the driving voltage VCC supplied from the driving voltage source VCC to the red LED array 110 through the first resistor R1 to a predetermined voltage level.

Accordingly, the voltage drop unit 100 controls the driving voltage supplied to the red LED array 110 to minimize the difference between the operating voltage Vf of the relatively low red LED and the operating voltage Vf of the relatively high green and blue LEDs. Reduce to the optimum voltage. For example, assuming that the voltage drop unit 100 is composed of ten series diodes and that the operation voltage Vf of each diode is 0.8V, the voltage drop unit 100 drops the driving voltage VCC-8V. The voltage is supplied to the red LED array 110.

Meanwhile, as illustrated in FIG. 5, the voltage drop unit 100 includes first to n-th diode transistors connected in series between the first resistor R1 connected to the driving voltage source VCC and the red LED array 110. (DT1 to DTn).

Each of the first to n-th diode transistors DT1 to DTn is a FET transistor having a diode type in which its gate terminal and source terminal are commonly connected.

The first through n-th diode transistors DT1 through DTn drop the driving voltage VCC supplied from the driving voltage source VCC through the first resistor R1 to a predetermined voltage level, thereby causing the red LED array 110 to fall. To feed.

The red LED array 110 illustrated in FIG. 3 includes first to fifth red LEDs R_LED1 to R_LED5 connected in series between the voltage drop 100 and the collector terminal of the first transistor Q1.

Each of the first to fifth red LEDs R_LED1 to R_LED5 is connected in series in the forward direction between the first resistor R1 and the collector terminal of the first transistor Q1.

The green LED array 120 includes first to fifth green LEDs G_LED1 to G_LED5 connected in series between the second resistor R2 connected to the driving voltage source VCC and the collector terminal of the second transistor Q2. do.

The second resistor R2 is a bias resistor for keeping the current supplied to the first to fifth green LEDs G_LED1 to G_LED5 constant.

Each of the first to fifth green LEDs G_LED1 to G_LED5 is connected in series in the forward direction between the second resistor R2 and the collector terminal of the second transistor Q2.

The blue LED array 130 includes first to fifth blue LEDs B_LED1 to B_LED5 connected in series between the third resistor R3 connected to the driving voltage source VCC and the collector terminal of the third transistor Q3. do.

The third resistor R3 is a bias resistor for keeping the current supplied to the first to fifth blue LEDs B_LED1 to B_LED5 constant.

Each of the first to fifth blue LEDs B_LED1 to B_LED5 is connected in series in the forward direction between the third resistor R3 and the collector terminal of the third transistor Q3.

The controller 140 generates the red, green, and blue control signals R_CS, G_CS, and B_CS to independently or commonly emit the red, green, and blue LED arrays 110, 120, and 130, respectively, to generate the first, second, and third control signals. The transistors Q1, Q2 and Q3 are respectively controlled.

The first transistor Q1 is electrically connected to a base terminal to which the red control signal R_CS is supplied from the controller 140 through the fourth resistor R4 and to the cathode electrode of the fifth red LED R_LED5. An emitter terminal is connected to the collector terminal and the ground voltage source (GND). The first transistor Q1 is turned on according to the red control signal R_CS to connect the red LED array 110 to the ground voltage source GND to emit light.

The second transistor Q2 is a collector electrically connected to the base terminal to which the green control signal G_CS is supplied from the controller 140 through the fifth resistor R5 and to the cathode electrode of the fifth green LED G_LED5. An emitter terminal connected to the terminal and the ground voltage source (GND). The second transistor Q2 is turned on according to the green control signal G_CS to connect the green LED array 120 to the ground voltage source GND to emit light.

The third transistor Q3 is a collector electrically connected to a base terminal supplied with the blue control signal B_CS from the controller 140 through the sixth resistor R6 and to a cathode electrode of the fifth blue LED B_LED5. An emitter terminal connected to the terminal and the ground voltage source (GND). The third transistor Q3 is turned on according to the blue control signal B_CS to connect the blue LED array 130 to the ground voltage source GND to emit light.

As described above, the LED array driving method using the LED array driving apparatus according to the embodiment of the present invention is as follows.

First, the controller 140 generates red, green, and blue control signals R_CS, G_CS, and B_CS to independently and / or commonly emit red, green, and blue LED arrays 110, 120, and 130. FIG. Here, when the red, green, and blue LED arrays 110, 120, and 130 emit light in common, the controller 140 generates red, green, and blue control signals R_CS, G_CS, and B_CS in a high state.

The red, green, and blue control signals R_CS, G_CS, and B_CS of the high state generated by the controller 140 are supplied to the base terminals of the first to third transistors Q1, Q2, and Q3, so that the first to third times. Transistors Q1, Q2 and Q3 are turned on.

As the first to third transistors Q1, Q2, and Q3 are turned on, the driving current from the driving voltage source VCC is supplied to the red, green, and blue LED arrays 110, 120, and 130, thereby providing red, green, and Generate red, green and blue light from each of the blue LED arrays 110, 120, 130. At this time, the red LED array 110 is supplied with a driving voltage dropped by the first to n th rectifying diodes D1 to Dn of the voltage drop unit 100.

Meanwhile, each of the red, green, and blue LED arrays 110, 120, and 130 may emit light sequentially or randomly according to a control signal from the controller 140.

The driving device and driving method of the LED array module according to the embodiment of the present invention reduces the driving voltage supplied to the red LED array 110 from the driving voltage source VCC using the voltage drop unit 100 to a constant voltage. As a result, heat generated by the first transistor Q1 emitting a red LED having a relatively low operating voltage is minimized.

The power consumption P of the first to third transistors Q1, Q2, and Q3 in the driving device and the driving method of the LED array module according to the embodiment of the present invention are shown in Table 2 below. Here, it is assumed that the driving voltage VCC supplied to the red LED array 110 is reduced to 8V by the voltage drop unit 100.

Q1 Q2 Q3 Driving voltage (VCC) 16 V 24V 24V Drive Current (If) 0.35A 0.35A 0.35A Operating voltage (Vf) 2 V 3.5 V 3.5 V Quantity (ea) 5ea 5ea 5ea Power Consumption (P = VCC- (Vf * Quantity) * If) 2.1 W 2.27 W 2.27 W

In addition, the driving device and driving method of the LED array module according to an embodiment of the present invention is to minimize the heat generated in the red LED array to reduce the area of the heat sink for radiating heat of the LED array size and cost of the LED array module This can be reduced.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification but should be defined by the claims.

As described above, the driving device and the driving method of the LED array module according to an embodiment of the present invention is supplied by dropping the driving voltage supplied to the red LED array of the red, green and blue LED array using the voltage drop unit As a result, heat generation of the transistor for emitting the red light emitting diode can be minimized.

Accordingly, the present invention can minimize the heat generation of the transistor for emitting a red light emitting diode to reduce the size and cost of the light emitting diode array module.

Claims (4)

A driving voltage source for supplying a driving voltage; A voltage drop unit including a first resistor R1 connected to the driving voltage source and one or more diodes connected in series with the first resistor R1 to drop a driving voltage; and a red LED connected in series with the voltage drop unit. An array; A second LED (R2) connected to the driving voltage source and a green LED array connected in series to the second resistor (R2); A blue LED array connected in series with a third resistor (R3) connected to the driving voltage source and the third resistor (R3); A first transistor connected between said red LED array and a ground voltage source; A second transistor connected between said green LED array and said base voltage source; A third transistor connected between the blue LED array and the base voltage source; And a control unit for controlling each of the first to third transistors. The method of claim 1, The voltage drop unit is a driving device of a light emitting diode array module, characterized in that the diode transistor. Supplying a driving voltage to a voltage drop including one or more diodes connected in series through a first resistor to reduce the driving voltage to generate a drop voltage; Supplying the drop voltage to a series of red LED arrays connected in series; Supplying the drive voltage to a green LED array connected in series through a second resistor; Supplying the drive voltage to a blue LED array connected in series through a third resistor; Switching the first transistor connected between the red LED array and the base voltage source, the second transistor connected between the green LED array and the base voltage source, and the third transistor connected between the blue LED array and the base voltage source, Emitting at least one of the first to third color LED arrays. The method of claim 3, And the operating voltage of the red LED array is lower than that of the green and blue LED arrays.

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