KR20150010179A - LED illumination device consisting of led blocks - Google Patents

Abstract

The present invention aims to configure circuits that include LED as blocks, thereby facilitating change in the circuit of LED units as needed. For this, provided is an LED lighting device that includes LED units consisting of blocks, the device including a power supply unit supplying input power; a rectifier circuit which receives the input power from the power supply unit to output a rectified power supply; LED units comprising blocks respectively including a circuit which includes multiple LED channels connected in series and has a resistor connected on the end of the LED channels; a block connection unit which has a matrix connection structure to implement a specific structure when the LED units comprising the blocks are connected to each other; and a switch circuit unit that includes a current sensing resistance and multiple switches, wherein the n-th switch is connected to the rear end of the LED channels to control the operation of the LED channels, and the sum of the currents of the n-th switch and the n+1-th switch flowing on the current sensing resistance controls the n-th switch.

Description

[0001] The present invention relates to an LED lighting device,

The present invention relates to an LED (Light Emitting Diode) lighting device, in which a switch for operating an LED is automatically switched by an input voltage, and an LED channel or an LED is formed into a block, The present invention relates to an LED lighting device that constitutes a device and solves a problem of heat generation occurring in a switching IC generated when a voltage is input at a rated voltage or higher.

In recent years, LED diodes (hereinafter referred to as LEDs) have been widely used in lighting devices due to their low power, high efficiency and long service life.

To use the LED as a light source, a switching circuit that operates the LED according to the input voltage is needed.

The conventional switching circuit includes a voltage sensing circuit or a period sensing circuit, and controls a switch corresponding to the LED by sensing a voltage level or a voltage input period according to an input voltage. However, since such a conventional switching circuit includes a voltage sensing circuit or a period sensing circuit, there arises a problem that the size of the entire circuit increases. Therefore, the area that can further include the LED is reduced.

In addition, the switching circuit is composed of FETs. Such FETs are susceptible to the invention because they are sensitive components. Here, when the input voltage is inputted at a rated voltage or more, there is a problem that a lot of heat is generated in the switching circuit. That is, when the input voltage is inputted at a rated voltage or higher, a high amperage current flows to the switching circuit, which causes a problem that a large amount of heat is generated in the switching circuit.

U.S. Patent No. 6,989,807 discloses a feature in which LEDs can be driven at a voltage varying in real time by adjusting a plurality of switches connected in parallel to a plurality of LED groups serially connected at an AC input voltage varying in voltage in real time , US Patent No. 6,989,807 also includes a voltage sensing circuit for sensing the input voltage. When the rated voltage is 100% or more, an excessive amount of heat is generated in the switching circuit, The efficiency is lowered, and the possibility of malfunction of the circuit due to the high heat generated in the switching circuit is increased.

In addition, conventionally, an LED to be used is fixed to constitute a circuit, so that the number of LEDs to be used is fixed, and there is a problem that a plurality of lighting apparatuses must be used in order to realize illumination with desired brightness.

In order to solve the conventional problems of the present invention, it is an object to constitute a circuit including an LED as a block so that the circuit of the LED unit can be easily changed as necessary.

It is a further object of the present invention to provide a switching IC circuit comprising a FET, which is constructed by connecting a resistor for heat dissipation to an LED unit to which a plurality of LEDs are connected, To reduce the heat generated by the switching IC circuit.

It is still another object of the present invention to provide a sensing resistor to automatically switch according to a voltage generated in a sensing resistor.

It is still another object of the present invention to provide a switch circuit unit without configuring a voltage sensing circuit or a periodic sensing circuit for sensing an input voltage so that an LED can be additionally formed in a limited area.

Other objects of the present invention will become readily apparent from the following description of the embodiments.

According to an aspect of the present invention, there is provided a liquid crystal display device including: a power supply unit for supplying input power; a rectifying circuit unit for receiving a rectified power supply from the power supply unit and outputting rectified rectified power; a plurality of LED channels connected in series, And an LED unit having a circuit structure in which a resistance unit is connected to a last end of the LED unit, and a matrix connection structure and having a specific connection structure when an LED unit including the block is connected; And the nth switch is connected to the rear end of the nth LED channel to control the operation of the LED channel, and the current of the nth switch flowing in the current sensing resistor and the current flowing through the n A switch circuit portion in which an nth switch is controlled by a sum of currents of the first and second switches; And a light emitting diode (LED) unit comprising a block including a light emitting diode.

Here, the plurality of LED units constituted by the blocks may be connected in parallel.

Here, the LED channel may include a block including one or more LEDs.

Here, the resistor unit is connected to the last switch of the switch circuit unit, and the resistor unit distributes and reduces heat generated in the switch circuit unit.

Here, the LED channel may include one or more LEDs.

Here, the n-th LED channel may have a different forward voltage Vf to reduce the power consumption of the n-th switch.

Here, the saturation current of the (n + 1) th switch is set higher than the saturation current of the nth switch.

Here, the voltage applied to the current sensing resistor is changed by the sum of currents flowing through the neighboring nth switch and the (n + 1) th switch, and the input voltage is greater than the forward voltage Vf of the And when the saturation current flows through the (n + 1) th switch, the nth switch is turned off.

According to the present invention, the circuit of the LED unit can be constituted as a block, and can be connected so as to operate at a desired voltage according to the user's need, so that a circuit capable of operating with maximum efficiency according to the input voltage of 110V or 220V can be constituted have.

Further, since the circuit of the LED unit can be easily changed, a circuit having desired brightness and efficiency can be formed according to the user's need.

Further, there is an effect that the forward voltage of the LED channel is redistributed to reduce the power consumed in the switch circuit portion, thereby increasing the efficiency.

Further, there is an effect that the switch for driving the LED can be automatically controlled according to the input voltage.

Also, there is an effect of providing an LED lighting device that connects a plurality of LED operation units in series or in parallel according to the magnitude of an input voltage, thereby emitting brighter light at the same input voltage.

1 is a diagram illustrating a structure of an LED illumination device including one LED according to an embodiment of the present invention.
2 is a diagram showing a circuit structure including one or more LED portions according to an embodiment of the present invention.
FIGS. 3 and 4 are diagrams illustrating a structure of an LED channel including one or more LEDs according to an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated in the drawings and described in detail in the detailed description. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. 1 < / RTI > and 2 or these terms are used only for the purpose of distinguishing one element from another. Also, the singular expressions may include plural expressions unless the context clearly dictates otherwise.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a diagram illustrating a structure of an LED illumination device including one LED according to an embodiment of the present invention.

The power supply unit 10 supplies input power. Since the power source unit 10 uses an AC power source, the magnitude of the input voltage periodically changes with time.

The rectifying circuit section 20 receives the AC input power from the power supply section 10 and outputs rectified rectified power.

The LED unit 30 receives power from the rectifying circuit unit 20 and performs a plurality of operations. A plurality of LED channels are connected in series and a resistor unit 35 is connected to a lower end of the last LED channel have.

Hereinafter, for convenience of explanation, it is assumed that n = 4.

The switch circuit unit 40 includes a plurality of switches 41, 42, 43, 44 and 45. The nth switch is connected to the rear end of the n-th LED channel to control the operation of the LED channel, The nth switch is controlled by the sum of the current of the nth switch and the current of the (n + 1) th switch.

The current sensing resistor 50 is connected to each switch 41, 42, 43, 44, 45 included in the switch circuit portion 40. Therefore, when a current flows through the switch, the current flowing through the current sensing resistor 50 becomes the sum of the currents flowing through the switch.

Referring to FIG. 1, the second LED channel 32 and the first switch 41 are connected to the next end of the first LED channel 31. The third LED channel 33 and the second switch 42 are connected to the next stage of the second LED channel 32. [ And the fourth LED channel 34 and the third switch 43 are connected to the next stage of the third LED channel 33. [ The resistor unit 35 and the fifth switch 44 are connected to the next stage of the fourth LED channel 34. [ The fifth switch 45 is connected to the next stage of the resistor 35. [

Here, each of the switches is composed of a FET (Field Effect Transistor). In particular, it is composed of an NMOS FET.

The current sensing resistor 50 is connected to each switch 41, 42, 43, 44, 45 included in the switch circuit portion 40. Therefore, when a current flows through the switch, the current flowing through the current sensing resistor 50 becomes the sum of the currents flowing through the switch.

The current sensing resistor 50 may be constituted by a variable resistor.

In the present invention, the LED channel operates according to the magnitude of the input power. The corresponding LED channel operates according to the magnitude of the rectified power input to the LED unit 30. [

The operation of the switch unit 40 of the present invention is as follows.

First, in the initial stage, all the switches 41, 42, 43, 44, and 45 are set to the on state.

The switch of the switch unit 40 is automatically controlled by the voltage value applied to the current sensing resistor 50 according to the magnitude of the rectified voltage input to the LED unit 30 to operate the LED channel.

The current sensing resistor 50 in the present invention is set to, for example, 10 ohms.

Table 1 below shows the saturation current value according to the switch (FET) and the voltage across the current sensing resistor 50 when the saturation current flows through the switch.

Here, Id denotes saturation current of the corresponding switch. Means a saturated voltage when a switch operates and current flows. Vrs denotes a voltage applied to the current sensing resistor 50.

Id (mA) Vrs 1 FET 20 0.2 2 FET 40 0.4 3 FET 60 0.6 4 FET 80 0.8 5 FET 100 1.0

It is also assumed that the forward voltage Vf of each LED channel is 50V.

In this case, when the input voltage rises to reach about 50 V, the first LED channel 31 operates and the current I1 flows slowly through the first switch 41. When the input voltage exceeds 50 V, the saturation current of 20 mA flows in the first switch 41 and the voltage applied to the current sensing resistor 50 becomes 0.2V.

When the input voltage rises to reach 100 V, the second LED channel 32 operates and the current I2 flows slowly through the second switch 42. At this time, in the current sensing resistor 50, the current flows by the sum of the current flowing in the first switch 41 and the current I2 flowing in the second switch 42. Therefore, the voltage of the current sensing resistor 50 gradually increases. When the voltage applied to the current sensing resistor 50 rises, the voltage Vgs1 input to the gate of the first switch 41 becomes relatively low, so that the first switch 41 is switched from the on state to the off state. When the input voltage gradually increases and the current I2 flowing in the second switch 42 gradually increases, the voltage applied to the current sensing resistor 50 gradually rises and the voltage value of Vgs1 is relatively low So that the first switch 41 is turned off.

When the input voltage becomes 100 V or more, the second switch 42 has a saturation current of 40 mA and the first switch 41 is completely turned off.

When the input voltage rises to reach about 150 V, the third LED channel 33 operates and the current I3 gradually flows through the third switch 43. At this time, in the current sensing resistor 50, a current flows as much as the sum of the current flowing in the second switch 42 and the current I3 flowing in the third switch 43. Therefore, the voltage applied to the current sensing resistor 50 is gradually increased. When the voltage applied to the current sensing resistor 50 rises, the voltage Vgs2 input to the gate of the second switch 42 becomes relatively low, so that the second switch 42 is switched from the on state to the off state. And when the voltage value of the current sensing resistor 50 gradually increases and the voltage value of Vgs2 becomes relatively low, the second switch 42 is turned off.

When the input voltage exceeds 150V, the third switch 43 is supplied with a saturation current of 60 mA and the second switch 42 is completely turned off.

As described above, according to the input voltage, when the switch starts to flow current to the (n + 1) th switch sequentially, the nth switch is turned off.

When the input voltage rises to reach 200 V, the fourth LED channel 34 operates and the currents I3 and I4 flow slowly through the third switch 43 and the fourth switch 44. [ At this time, the current flows through the current sensing resistor 50 by the sum of the current flowing through the third switch 43 and the current flowing through the fourth switch 44 and the fifth switch 45. Likewise, when the input voltage becomes 200 V or more, the fourth switch 44 is supplied with a saturation current of 80 mA and the third switch 43 is completely turned off.

However, when a voltage higher than the rated voltage is input (for example, about 250 V), the fourth switch 44 is turned off and the fifth switch 45 is operated only for the same reason.

Assuming that an LED channel is connected instead of a resistor at the position of the resistor 35 as in the conventional case, when an input voltage higher than the rated voltage is inputted, an excessive current flows to the switch 45, do. That is, excessive current is generated in the switch for operating the last LED channel. Therefore, excessive heat generated in this way has a considerably bad influence on the switch circuit portion 40 composed of the IC parts, resulting in a failure of the component and a reduction in efficiency due to the generated heat.

Therefore, when the resistor 35 is connected to the last end of the LED 30 as in the present invention and the voltage is divided by the resistor 35, The heat generated by the fifth switch 45 is prevented from being excessively generated. Thus, in the present invention, even when the input voltage is inputted at a rated voltage or higher, excessive heat generated in the switch circuit portion 40 is partially distributed in the resistor portion 35 and is generated, thereby causing the switch circuit portion 40, And the stability of the switch circuit portion 40 can be maintained.

In addition, the present invention can have the following characteristics in terms of power consumption.

When the input voltage rises from the first switch to the fourth switch, the voltage is canceled by the forward voltage in the n-th LED channel and the n-th switch is operated with the remaining voltage. When the voltage higher than the forward voltage is inputted, (N + 1) switches are operated. Therefore, the power consumed by each switch increases, but the overall power consumption is within a predetermined system specification range. However, when the fifth switch 45, which is the last switch, receives a rated voltage or more, excessive current flows and the consumed power (heat) exceeds the specification range of the system. Therefore, when the rated voltage or more is inputted, the fifth switch 45 generates excessive heat.

In the present invention, even when a resistor unit 35 is provided and a rated voltage or more is inputted, the heat generated in the fifth switch 45 can be canceled by generating heat in the resistor unit 35.

Also, in the present invention, the forward voltage Vf of each LED channel is redistributed differently, so that power consumed by each switch can be made almost equal. That is, the forward voltage Vf of the (n + 1) -th LED channel is made higher than the forward voltage Vf of the nth LED channel, and the powers consumed by the nth and (n + 1) . By redistributing the forward voltage Vf of the LED channel in this way, even when the input voltage changes, the heat generated in the switch circuit 40 can be made equal.

Here, the forward voltage Vf can be freely changed and arranged for each LED channel, but the sum of the forward voltages Vf is set to the maximum value of the input voltage.

2 is a diagram showing a circuit structure including one or more LED portions according to an embodiment of the present invention.

In the present invention, the LED unit 30 can be constituted by a block. Accordingly, the LED units 30 constituted of the blocks may be connected in parallel as shown in FIG. 2 by using a plurality of blocks to constitute an illuminating device having an LED unit configured in a parallel structure.

For this purpose, the LED lighting device including the LED unit constituted by the blocks of the present invention comprises a block connection unit having a matrix connection structure.

The LEDs 30 constituted of blocks are formed in a block structure having a constant connection structure, and can be connected to the block connection portions by interleaving. That is, the matrix structure of the block connection portion may be interposed between the LED portion 30 constituted by the blocks of the block connection portion so as to have a desired circuit structure to have a desired circuit structure. For example, as shown in FIG. 2, the block connection part is connected to have a plurality of parallel connection structures, and the LED parts 30_1, 30_2, and 30_3 constituted of blocks are formed by fitting the LED part 30 at a corresponding position It is possible to have parallel connection structures with each other.

 As shown in FIG. 2, when the same input voltage is input in the case where the LED units 30_1, 30_2, and 30_3 are connected in parallel to each other, a lighting device having three times brightness as compared with the lighting device composed of one LED 30 .

In FIG. 2, the LED unit is formed as a block and connected to the block connection unit. However, a desired circuit may be formed by connecting the LED channel to the block connection unit.

FIGS. 3 and 4 are diagrams illustrating a structure of an LED channel including one or more LEDs according to an embodiment of the present invention.

2, the circuit structure in which the brightness of the illumination is increased by connecting the at least one LED unit 30 in parallel with the LED unit 30 as a block has been described. However, the LED channels 31, 32, 33, And one or more LED channels 31, 32, 33, and 34 may be connected to a block connection portion having a matrix connection structure to form an illumination device having desired illumination brightness and illumination color.

For example, the LED channel 31 including four LEDs connected in series as shown in FIG. 3 can be configured as one block.

Or an LED unit 32 having a structure in which four LEDs connected in series as shown in FIG. 4 are grouped and a group including four LEDs are connected in parallel, as shown in FIG. 4, for example.

By configuring the structure including the LED as a block, it is possible to configure the LED block according to the input voltage according to the input voltage of 110V or 220V. That is, it is possible to easily implement an LED circuit having the maximum efficiency according to the magnitude of the input voltage.

Here, each of the blocks may be configured to have different illumination colors.

The LED lighting apparatus of the present invention having the above-described configuration has the following advantages.

① Switching of FET switch can be performed automatically according to input voltage without configuring input voltage sensing circuit or input period sensing circuit.

(2) Since the switch circuit can be configured easily, extra LED channels can be added for the same area.

(3) By rearranging the forward voltage Vf for each LED channel, it is possible to increase the efficiency of the switch circuit and to perform a combination of free LEDs.

(4) If a plurality of LED operation units are connected in series, the brightness of the n-th LED operation unit can be n times as high as that of using only one of the LED movement units.

(5) By connecting the LED channel or the LED unit constituted by the blocks to the block connection unit, it is possible to easily realize the circuit of the lighting device having the desired illumination brightness or illumination color.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention as defined in the following claims And changes may be made without departing from the spirit and scope of the invention.

10:
20:
30, 30_1, 30_2, 30_3, 30_4:
31, 32, 33, 34:
35:
40: Switch circuit part
41, 42, 43, 44, 45:
50: Current sensing resistance

Claims (8)

A power supply unit for supplying input power;
A rectifier circuit unit receiving the input power from the power unit and outputting rectified rectified power;
An LED unit having a circuit structure in which a plurality of LED channels are connected in series and a resistor unit is connected to a last end of the LED channel;
A block connection part having a matrix connection structure and having a specific connection structure when an LED part composed of the blocks is connected;
Current sensing resistance: and
And the nth switch is connected to the rear end of the nth LED channel to control the operation of the LED channel, and the current of the nth switch flowing in the current sensing resistor and the current of the n + 1th switch A switch circuit portion in which an nth switch is controlled by the sum of the nth switches; And an LED unit including a block including a light emitting diode.
The method according to claim 1,
Wherein the plurality of LED units are connected in parallel to each other.
The method according to claim 1,
Wherein the LED channel comprises a block including one or more LEDs. ≪ RTI ID = 0.0 > 11. < / RTI >
4. The method according to any one of claims 1 to 3,
Wherein the resistor unit is connected to the last switch of the switch circuit unit, and the resistor unit distributes and reduces heat generated in the switch circuit unit, and the LED unit includes the LED unit.
4. The method according to any one of claims 1 to 3,
Wherein the LED channel comprises one or more LEDs. ≪ RTI ID = 0.0 > 11. < / RTI >
4. The method according to any one of claims 1 to 3,
Wherein the plurality of LED channels have different forward voltages (Vf) to reduce power consumption in the respective switches.
4. The method according to any one of claims 1 to 3,
and the saturation current of the (n + 1) th switch is set higher than the saturation current of the nth switch.
4. The method according to any one of claims 1 to 3,
The voltage across the current sensing resistor is changed by the sum of the currents flowing through the neighboring n-th switch and the n + 1-th switch,
And the nth switch is turned off when the input voltage is equal to or greater than the forward voltage Vf of the (n + 1) th LED channel and a saturation current flows through the (n + 1) th switch. Including an LED lighting device.

Images