KR20070006073A - Luminous device - Google Patents

Abstract

An LED(light emitting device) is provided to simplify a fabricating process and reduce the size of a light emitting device by using an LED chip to which a plurality of light emitting cells are connected. A light emitting part has an LED chip(100). A protection unit protects the light emitting part from abrupt generation of an abnormal voltage, connected in parallel with the light emitting part and including a varistor or a Zener diode. The light emitting part and the protection unit are surrounded by a package. A resistor connected in series to the light emitting part is further included.

Description

Luminous Device

1 is a circuit diagram of a conventional AC light emitting device.

2 is a circuit diagram of a light emitting device according to a first embodiment of the present invention.

3 is a perspective view of a light emitting device according to a first embodiment of the present invention;

4 is a perspective view of a light emitting device according to another modification of the first embodiment of the present invention;

5 is a cross-sectional view illustrating a varistor mounted on a submount substrate.

6 is a circuit diagram of a light emitting device according to another modification of the first embodiment of the present invention.

7 is a circuit diagram of a light emitting device according to a second embodiment of the present invention.

8 is a perspective view of a light emitting device according to a second embodiment of the present invention;

9 is a circuit diagram of a light emitting device according to a third embodiment of the present invention.

10 is a perspective view of a light emitting device according to a third embodiment of the present invention;

11 is a circuit diagram of a light emitting device according to a fourth embodiment of the present invention.

12 is a perspective view of a light emitting device according to a fourth embodiment of the present invention.

13 is a circuit diagram of a light emitting device according to a fifth embodiment of the present invention.

14 is a perspective view of a light emitting device according to a fifth embodiment of the present invention;

<Explanation of symbols for main parts of the drawings>

1 power conversion unit 2 light emitting unit

3: full wave rectification circuit 4: bridge portion

100, 200, 300, 400: LED chip 110: body

111: metal pattern 112: heat sink

121, 122, 123, 124. 125, 126: internal electrode terminals

131, 132, 133, 134: external electrode terminal

141, 142, 143, 144, 145, 146: wire

150: phosphor 160: molding part

171, 172: jumper 180: submount substrate

The present invention relates to a light emitting device, and more particularly, to an alternating light emitting device using one or more LED chips connected in series, parallel, or parallel and in series in one package to an AC power source. It is about.

A light emitting diode (LED) refers to a device that generates a small number of carriers (electrons or holes) injected using a P-N junction structure of a compound semiconductor, and emits predetermined light by recombination thereof. Such light emitting diodes have been used as display devices and backlights, and researches for applying them to general lighting applications have recently been actively conducted.

The light emitting device using the light emitting diode has a small power consumption and a lifetime of several to several tens of times compared to a conventional light bulb or a fluorescent lamp, and is superior in terms of power consumption reduction and durability.

In general, in order to use a light emitting diode for lighting, a light emitting device is formed through a separate packaging process, a plurality of individual light emitting devices are connected in series through wire bonding, and a protective circuit and an AC / DC converter are installed from the outside. Made in the form of a lamp.

1 is a conceptual diagram of a conventional AC light emitting device, in which a power converter 1 for converting AC power into DC power and a light emitting part 2 in which a plurality of LEDs 10-1 to 10-n are connected in series; It includes.

The power converter 1 includes a full-wave rectification circuit 3 for full-wave rectification of AC 220V or 110V, and a resistor R1 for voltage dropping the full-wave rectified power. The full-wave rectifying circuit 3 includes first to fourth diodes D1 to D4 respectively connected between the first to fourth nodes N1 to N4, and the first node N1 and the third node N3. ) Includes a bridge portion 4 connected to an AC power supply, and a capacitor C1 connected to a second node N2 and a fourth node N4 of the bridge portion 4. The apparatus further includes a voltage drop capacitor connected between the external power supply and the first node N1.

In the light emitting part 2, the first to nth LEDs 10-1 to 10-n are connected in series between the resistor R1 and the second node N2 through a wire. Where n is an integer.

In such a conventional light emitting device, the power conversion unit 1 is configured on a first printed circuit board. The individual LEDs of the light emitting portion 2 are also mounted on the second printed circuit board and then connected in series via wires. Subsequently, the light emitting device was implemented by electrically connecting the first and second printed circuit boards.

However, in the light emitting device, the capacitor C1 provided in the power conversion unit 1 drops the AC voltage of 220V to the required voltage, but has a problem of shortening the overall life of the light emitting device because its life is very short compared to the LED.

In addition, a separate connection node must be provided between the light emitting device and the power supply in order for the resistor located between the light emitting device and the power supply to drop the AC power of 220V. Therefore, there is a problem that the connection between them may become unstable, and the overall resistance value may be changed by the resistance value of the node itself.

 In addition, when there are a plurality of LEDs connected in series to the light emitting unit, a connection board for connecting each LED is required, which increases the cost for connecting each LED in series. For example, if the number of LEDs is 20, at least 19 wires are also used to connect them. In addition, each LED provided in the connection substrate has a limit in realizing a high quality light source due to a large light emitting area. Moreover, the simple linear arrangement between the light emitting elements causes the manufacturing cost to increase when the number of LEDs is increased to increase the light emitting efficiency.

In addition, the conventional light emitting device is unstable due to sudden voltage rise due to electrostatic discharge (ESD) or surge due to lightning, etc., which shortens the lifespan of the LED chip. There was a hassle to mount the device.

The present invention is to solve the above problems, to manufacture a LED chip connected to a plurality of light emitting cells at the wafer level, by connecting the LED chip to simplify the manufacturing process, increase the luminous efficiency, manufacturing cost and defect rate It is an object to provide a light emitting device which is reduced and advantageous for mass production.

Another object of the present invention is to insert a varistor into the package to easily protect the LED chip from electrostatic discharge or surge voltage without a separate circuit protection device, thereby improving the life of the LED chip.

Another object of the present invention is to insert a resistor such as a resistor or a PTC inside the package to stabilize the current of the LED chip and to maintain a constant luminous efficiency.

In order to achieve the above object, the present invention provides a light emitting portion having an LED chip, and a protection means connected in parallel with the light emitting portion to protect the light emitting portion from the sudden occurrence of abnormal voltage, the light emitting portion and the protection means It provides an LED light-emitting device comprising a package surrounding the. The protection means may comprise a varistor or zener diode, characterized in that it is connected in parallel with one or more of the LED chips.

The resistor may further include a resistor connected in series with the light emitting part, and the resistor may include a resistor or a PTC.

The light emitting unit may further include a rectifier circuit electrically connected to the LED chip.

The protection means may be located in an adjacent area of the LED chip inside the package.

A heat sink may be further included in the package, and the heat sink may be provided under the LED chip. In addition, the protection means may be mounted in the heat sink.

Hereinafter, with reference to the accompanying drawings will be described an embodiment of the present invention in more detail. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms, and only the embodiments are intended to complete the disclosure of the present invention, and to those skilled in the art to fully understand the scope of the invention. It is provided to inform you. Like numbers refer to like elements in the figures.

2 is a circuit diagram of a light emitting device according to a first embodiment of the present invention. 3 is a perspective view of a light emitting device according to a first embodiment of the present invention.

2 and 3, the light emitting device according to the present embodiment includes a varistor V10 connected between a first node N10 and a second node N20, a first node N10, and a second node ( The LED chip 100 in which a plurality of cell blocks 500a and 500b including a plurality of light emitting cells connected in parallel and connected in parallel to N20 are anti-parallel connected between the first pad P10 and the second pad P20. ).

Here, the first node N10 and the second node N20 are connected to an AC power source through the external electrode terminals 131 and 132.

In the LED chip 100, two cell blocks 500a and 500b are antiparallelly connected between the first pad P10 and the second pad P20. LED chip 100 of the present invention is a form in which each of the plurality of light emitting cells (100-1 to 100-n) are connected. That is, in the first cell block 500a, the P electrode of the first light emitting cell 100-1 is connected to the P-type pad, and the N electrode is connected to the P electrode of the second light emitting cell 100-2. . The N electrode of the second light emitting cell 100-2 is connected to the P electrode of the third light emitting cell 100-3. The N electrodes of the n-th light emitting cells 100-n-1 which are sequentially connected in this way are connected to the P electrodes of the n-th light emitting cells, and the N electrodes of the n-th light emitting cells 100-n are connected to the N-type pads. Connected. The second cell block is also connected in the same manner, so that the P electrode of the first light emitting cell 100-1 is connected to the P type pad and the N electrode of the nth light emitting cell 100-n is connected to the N type pad. . Thus, the P-type pad of the first cell block 500a and the N-type pad of the second cell block 500b are connected to the first pad P10, and the N-type pad and the second cell of the first cell block 500a are connected. The P-type pad of block 500b is connected to the second pad P20. Of course, the present invention is not limited thereto, and the LED chip 100 of the present invention may have a plurality of anti-parallel cell blocks in which a plurality of light emitting cells are connected in series between the first pad P10 and the second pad P20. .

Referring to the operation of the varistor and the LED chip 100 of the present embodiment having the above-described configuration based on the home AC power supply as follows.

When the positive voltage (+) is applied to the first pad P10 and the negative voltage (−) is applied to the second pad P20, the LED chip 100 emits light by the first cell block 500a. do. On the other hand, when the positive voltage (+) is applied to the second pad (P20) and the negative voltage (-) is applied to the first pad (P10), the LED chip 100 by the second cell block (500b). It will emit light. The number of light emitting cells in the LED chip 100 may vary depending on the size of the AC power source used.

In this way, the voltage is applied from the outside to emit the LED chip irrespective of the direction of the voltage, the varistor connected in parallel with the LED chip is an external such as lightning or spark through the external electrode terminals (131, 132) The momentary overvoltage due to the factor or the circuit itself causes the resistance to drop suddenly when a sudden abnormal voltage such as a surge occurs, which serves to bypass the current by reaching the breakdown voltage. Thus, it is possible to prevent damage to the LED chip due to ESD discharge or surge due to lightning, etc., and to improve its life.

The light emitting device of the present embodiment having the above-described circuit diagram will be described below with reference to FIG. 3.

The light emitting device of this embodiment includes a package including a body 110 and a molding unit 160, a light emitting unit having an LED chip 100 inside the package, and a protection means for protecting the light emitting unit.

Specifically, the LED chip 100 having a plurality of cell blocks including a plurality of light emitting cells connected in series mounted on the body 110 is connected in parallel and a first internal electrode terminal formed in the body 110. LED chips 100 including varistors V10 connected between the first to fourth internal electrode terminals 121 and the first to fourth internal electrode terminals 124, and between the first to fourth internal electrode terminals 124. Phosphor 150 is thinly coated on, and the molding unit 160 for encapsulating the LED chip 100.

The apparatus further includes a first external electrode terminal 131 connected to the first internal electrode terminal 121, and a second external electrode terminal 132 connected to the third internal electrode terminal 123.

Here, the body 110 uses a shape in which the circumference protrudes in a circular shape as shown in FIG. 3. The body 110 may use an insulated poly phthalide (PPA) resin, a thermal conductive resin, or the like. The shape of the body 110 is also not limited to the circular shape, various shape modifications are possible. A circular metal pattern 111 is formed on the body, and two axes extending from the metal pattern 111 are exposed to the outside of the circular body 110. The metal pattern 111 may emit heat generated from the LED chip 100 to the outside. In addition, the center of the body 110 may further include a heat sink 112 for dissipating heat of the LED chip to the outside. It is preferable to use a material having excellent thermal conductivity as the heat sink 112, and it is most preferable to use a metal having excellent thermal conductivity and electrical conductivity. To this end, a portion of the body 110, that is, a region in which the LED chip 100 is to be removed is formed to form a through hole, a heat sink 112 is inserted into the through hole, and then an upper portion of the heat sink 112 is formed. The LED chip 100 may be mounted on the LED chip 100.

A portion of the first internal electrode terminal 121 to the fourth internal electrode terminal 124 is exposed to the outside of the body. The first internal electrode terminal 121 and the third internal electrode terminal 123 are connected to the first external electrode terminal 131 and the second external electrode terminal 132. Of course, the present invention is not limited thereto, and the second internal electrode terminal 122 and the fourth internal electrode terminal 124 may also be connected to separate external electrode terminals.

In this embodiment, the metal oxide varistor MOV is used as the varistor V10 described above. The connection relationship between the varistor and the LED chip is as follows.

The varistor V10 is connected between the first internal electrode terminal 121 and the fourth internal electrode terminal 124. The first internal electrode terminal 121 is connected to the first bonding pad of the LED chip 100 through the first wire 141. The fourth internal electrode terminal 124 is connected to the second bonding pad of the LED chip 100 through the second wire 142. The second bonding pad of the LED chip 100 is connected to the third internal electrode terminal 123 through the third wire 143.

When the positive voltage (+) is applied to the first internal electrode terminal 121 and the negative voltage (-) is applied to the third internal electrode terminal 123 through the above-described connection relationship, the positive voltage (+) is the first It is applied to the first bonding pad of the LED chip 100 through the internal electrode terminal 121 and the first wire 141, the negative voltage (-) is the third internal electrode terminal 123 and the third wire 143 It is applied to the second bonding pad of the LED chip 100 through. As a result, the LED chip 100 emits light. In addition, the varistor V10 is applied with a positive voltage (+) through the first internal electrode terminal 121, and has a third internal electrode terminal 123, a third wire 143, a second bonding pad, and a second wire. A negative voltage (−) is applied through 142 to be connected in parallel with the LED chip 100. Light emission with LED chip 100 in case of sudden abnormal voltage such as surge due to external overvoltage due to external factors such as lightning or spark or external circuit such as spark itself through external electrode terminals 131 and 132 In order to protect the negative and the circuit from instantaneous overvoltage, the resistance of the varistors V10 and V20 is rapidly lowered to bypass the current at the breakdown voltage. Thus, damage to the LED chip 100 due to surges due to ESD discharge or lightning may be prevented, and the life thereof may be improved.

On the other hand, when a positive voltage (+) is applied to the third internal electrode terminal 123 and a negative voltage (-) is applied to the first internal electrode terminal 121, the LED chip 100 emits light as described above. The varistor V10 connected in parallel with the LED chip 100 may protect the LED chip 100 from ESD discharge or surge voltage as described above.

The present embodiment uses a metal oxide varistor (MOV) to protect the LED chip 100. However, the present invention is not limited thereto, and any component having a bidirectional zener diode or an electrical characteristic typically used for surge protection may be used. In addition, the varistor V10 is disposed inside the package together with the LED chip 100 so that a separate circuit protection device does not need to be mounted.

Since the light emitting device of the present invention uses an LED chip that can be driven even by an AC power source, it is possible to emit light from an AC power source regardless of the direction of the voltage without a complicated circuit. However, the present invention is not limited thereto, and a light emitting device capable of driving AC may be manufactured by connecting a rectifier circuit for converting AC power to DC power and an LED chip. In this case, even if an LED chip including a plurality of light emitting cells connected in series is used, the rectifier circuit can drive the AC power.

Phosphor 150 may be thinly coated on the LED chip 100. As the phosphor 150, a phosphor having a garnet structure or a silicate structure is used, and various kinds of phosphors may be used as long as the LED chip 100 may emit light having a desired color by converting a wavelength of light emitted from the LED chip 100. For example, the YAG: Ce phosphor is ported onto the LED chip 100 emitting blue to implement white color. In this case, the phosphor 150 and the molding unit 160 may be manufactured through separate processes, or the phosphor 150 may be uniformly distributed in the molding unit 160. The molding part 160 is thinly formed in a dome shape in the protrusion of the body 110. Of course, the present invention is not limited thereto, and the shape of the molding part and the molding area may be variously changed.

The manufacturing method of the light emitting device having the above-described structure may be very diverse, but the manufacturing method is briefly described as follows.

A body in which a plurality of electrode terminals are formed is provided, and a varistor is provided. An LED chip connected with a plurality of cell blocks including a plurality of light emitting cells connected in series is mounted on a body, and a varistor is mounted between adjacent electrode terminals. Next, the wires are electrically connected between the varistor, the LED chip, and the internal electrode terminals. After the phosphor is coated on the LED chip thinly, a molding process is performed to form a molding unit, thereby manufacturing a light emitting device.

Thereby, the light emitting device which consists of a light emitting part provided with an LED chip, the protection means connected in parallel with the said light emitting part, and the package surrounding the said light emitting part and a protection means can be manufactured.

The present invention is not limited to the above description, and a separate member and a manufacturing process may be further inserted to improve the efficiency of the light emitting device.

For example, a through hole may be formed by removing a portion of the body, that is, an area where the LED chip is to be mounted, insert a heat sink into the through hole, and then mount the LED chip on the heat sink. If the body itself is used as a metal, it can be used as a heat sink. In addition, the LED chip may further include a reflective member for centralizing the light emitted, or may further include a diffuse reflection pattern member for diffusing the light. In addition, the present invention may add a capacitor and a resistor connected in parallel to the above-described structure to reduce the number of light emitting cells in the LED chip, and to improve brightness and brightness.

In the light emitting device of the present invention, the varistor is not mounted between the internal electrode terminals, but may be mounted in an adjacent region of the LED chip. 4 is a perspective view showing a light emitting device according to another modification of the first embodiment. This is almost the same as in the above first embodiment, but the varistor is mounted inside the heat sink just like the LED chip as shown. At this time, the varistor is mounted as shown in FIG. The varistor V10 is mounted on a separate sub-mount substrate 180 on which electrode patterns 181 and 182 are formed, which are provided around the LED chip 100 on the heat sink 112. The varistor V10 includes varistor electrode terminals 101 and 102 at both ends thereof and is connected to electrode patterns 181 and 182 formed on the submount substrate 180, respectively.

In the light emitting device, when the positive voltage (+) is applied to the first internal electrode terminal 121 and the negative voltage (-) is applied to the third internal electrode terminal 123, the positive voltage (+) is the first voltage. The first bonding pad of the LED chip 100 is applied through the internal electrode terminal 121 and the third wire 143, and a negative voltage (−) is applied to the third internal electrode terminal 123 and the fourth wire 144. It is applied to the second bonding pad of the LED chip 100 through. In addition, the varistor V10 is applied with a positive voltage (+) through the first internal electrode terminal 121, the first wire 141, and the first electrode pattern 181, and receives the third internal electrode terminal 123 and A negative voltage (−) is applied through the second wire 142 and the second electrode pattern 182, and is connected in parallel with the LED chip 100. Light emitting unit and circuit with LED chip in case of sudden abnormal voltage such as surge due to external overvoltage due to external factors such as lightning or spark or external circuit such as spark itself through external electrode terminals 131 and 132 In order to protect against transient overvoltage, the resistance of the varistors V10 and V20 is drastically lowered to bypass the current at the breakdown voltage. Thus, it is possible to prevent damage to the LED chip due to ESD discharge or surge due to lightning, etc., and to improve its life.

Meanwhile, when the positive voltage (+) is applied to the third internal electrode terminal 123 and the negative voltage (−) is applied to the first internal electrode terminal 121, the LED chip 100 emits light as described above. It can operate stably even with ESD discharge or surge voltage.

As such, the position of the varistor V10 may be located in an adjacent region of the LED chip 100 within the package, and the present invention is not limited thereto and may be disposed at various positions, thereby improving flexibility of the process.

In the present invention, the external resistor R may be further added to the above-described embodiment as shown in the circuit diagram shown in FIG. As an external resistor, a chip resistor or a positive temperature co-efficient may be used. The fixed resistor can not prevent the LED array's forward voltage drop (V _F ) from dropping significantly depending on the heat sink temperature, so that the current applied to the LED does not increase as the temperature rises with only the fixed resistor. Therefore, by using PTC, the resistance value of PTC becomes large in proportion to the heat sink temperature, thereby stabilizing the LED current and making the luminous efficiency constant. Of course, the chip resistor and PTC can be used simultaneously. In addition, the resistor may be disposed inside the package like the varistor.

7 and 8 are related to the second embodiment of the present invention, wherein the light emitting device is parallel to two LED chips 100 and 200 and a resistor R10 connected in series and to each LED chip 100 and 200, respectively. And connected first and second varistors V10 and V20. In the following embodiment, a description overlapping with the first embodiment described above will be omitted.

The varistors V10 and V20 are connected to the first and second LED chips 100 and 200 in parallel, respectively, and bypass the varistors by themselves. In addition, in the resistor R10 connected in series between the first and second LED chips 100 and 200, the resistance value of the PTC is increased in proportion to the heat sink temperature using PTC, so that the current of the LED chips 100 and 200 is increased. Is stabilized and the luminous efficiency is constant. That is, it is possible to maintain a constant brightness irrespective of the temperature rise caused by driving the LED. Of course, the present invention is not limited thereto, and other materials having a predetermined resistance component may be used. In addition, a plurality of resistors may be configured in the circuit.

When a current is applied through the external electrode terminals 131 and 132, current flows through the first LED chip 100, the resistor R10, and the second LED chip 200 to emit light during normal operation. In the event of a sudden abnormal voltage, such as a resistor, the resistance of the varistors V10 and V20 rapidly decreases, thereby bypassing the current. Thus, it is possible to prevent damage to the LED chip due to ESD discharge or surge due to lightning, etc., and to improve its life.

The light emitting device of this embodiment shown in FIG. 8 is almost the same as that of FIG. 4, except that the LED chips 100 and 200, the varistors V10 and V20, and the resistor R10 are mounted on the heat sink 112. A separate submount substrate 180 is provided.

When the positive voltage (+) and the negative voltage (-) are respectively applied to the first and third internal electrode terminals 121 and 123, the positive voltage (+) is the first internal electrode terminal 121 and the first wire. 141 is applied to the first electrode pattern 181 of the submount substrate 180, and a negative voltage (−) is applied to the submount substrate (the third internal electrode terminal 123 and the second wire 142). It is applied to the second electrode pattern 182 of 180. Accordingly, the first and second LED chips 100 and 200 connected in series between the first and second electrode patterns 181 and 182 of the sub-mount substrate 180 emit light, and the LED chips 100 and 200 emit light. The first and second varistors (V10, V20) connected in parallel to each other have a resistance when a sudden abnormal voltage such as surge occurs due to an instantaneous overvoltage due to an external factor such as lightning or spark or the circuit itself. This is drastically lowered and serves to bypass the current by reaching the breakdown voltage. Thus, it is possible to prevent damage to the LED chip due to ESD discharge or surge due to lightning, etc., and to improve its life.

Meanwhile, when the positive voltage (+) is applied to the third internal electrode terminal 123 and the negative voltage (−) is applied to the first internal electrode terminal 121, the LED chip 100 emits light as described above. And, the operation of the varistor (V10, V20) and the resistor (R10) is the same as above.

9 and 10 illustrate a third embodiment of the present invention, wherein a light emitting device includes two LED chips 100 and 200 and a resistor R10 connected in series, and first and second varistors connected in parallel thereto. V10, V20). This is almost the same as the second embodiment shown in FIG. 7, and the first and second varistors V10 and V20 are formed in a light emitting part including two LED chips 100 and 200 and a resistor R10 connected in series. ) Are connected in parallel. Its operation is the same as that of the second embodiment.

Similarly, the light emitting device of this embodiment shown in FIG. 10 is almost the same as the second embodiment shown in FIG. 8, and only the LED chips 100 and 200 mounted on the submount substrate 180 according to the circuit diagram of FIG. 9. ), Varistors V10 and V20, and resistor R10 connect the shape of the pattern.

11 and 12 illustrate a fourth embodiment of the present invention, wherein a light emitting device includes a plurality of LED chips 100 to 400 connected in series and a first connection connected to the plurality of LED chips 100 to 400 in parallel. And second and second varistors V10 and V20 and first and second resistors R10 and R20 connected in series with the plurality of LED chips 100 to 400. In the following embodiments, descriptions overlapping with those of the first to third embodiments described above will be omitted.

In more detail, the first varistor V10 connected between the first node N10 and the second node N20, and the second node connected between the third node N30 and the fourth node N40. The first resistor R10 connected between the varistor V20, the second node N20, and the third node N30, and the second connected between the fourth node N40 and the first node N10. It includes a resistor (R20) and includes a first to fourth LED (100 to 400) chip connected in series between the second node (N20) and the fourth node (N40). Here, the first node N10 and the third node N30 are connected to the AC power source through the external electrode terminals 131 and 133.

When a current is applied through the external electrode terminals 131 and 132, in normal operation, the current passes through the second resistor R20, the LED chips 100 to 400, and the first resistor R10, and emits light. Through the electrode terminals 131 and 132, a light emitting part and a circuit equipped with an LED chip in case of sudden abnormal voltage such as surge due to an instantaneous overvoltage due to external factors such as lightning or spark or the circuit itself In order to protect against instantaneous overvoltage, the resistance of the varistors V10 and V20 is drastically lowered to bypass the current at the breakdown voltage. Thus, it is possible to prevent damage to the LED chip due to ESD discharge or surge due to lightning, etc., and to improve its life.

The light emitting device of this embodiment illustrated in FIG. 10 includes a plurality of LED chips 100 to 400 mounted on the heat sink 112 of the body 110, and is connected between the internal electrode terminals 121 to 126. First and second varistors V10 and V20, and first and second resistors R10 and R20.

When a positive voltage (+) is applied to the first internal electrode terminal 121 and a negative voltage (-) is applied to the fourth internal electrode terminal 124, the positive voltage (+) is applied to the first internal electrode terminal 121. The first resistor R10, the second internal electrode terminal 122, and the first wire 141 are applied to the first bonding pad of the first LED chip 100, and the negative voltage (−) is applied to the fourth internal portion. The electrode terminal 124, the second resistor R20, the fifth internal electrode terminal 125, and the fifth wire 145 are applied to the second bonding pad of the fourth LED chip 400. The four LED chips 100 to 400 connected in series are positive voltages (+) applied to the first bonding pads of the first LED chip 100 and negative voltages applied to the second bonding pads of the fourth LED chip 400. Light is emitted by the voltage (-). In addition, a positive voltage (+) is applied to the first varistor V10 through the first internal electrode terminal 121, the first resistor R10, and the second internal electrode terminal 122, and the fourth internal electrode terminal ( A negative voltage (-) is applied through the second jumper 172 and the third internal electrode terminal 123, and is connected in parallel with the LED chips 100 to 400. In addition, a positive voltage (+) is applied to the second varistor V20 through the first internal electrode terminal 121, the first jumper 171, and the sixth internal electrode terminal 126, and the fourth internal electrode terminal ( 124, a negative voltage (−) is applied through the second resistor R20 and the fifth internal electrode terminal 125 to be connected in parallel with the LED chips 100 to 400. The first and second varistors V10 and V20 connected as described above have a sudden decrease in resistance when a surge applied from the outside suddenly increases, and serves to bypass current above a normal operating voltage, thereby preventing the LED chip. To protect. In addition, the resistors connected in series with the LED chips 100 to 400 use PTC to increase the resistance value according to the temperature rise according to the driving of the LED, thereby stabilizing the current of the LED chip and maintaining a constant brightness.

On the other hand, when a positive voltage (+) is applied to the fourth internal electrode terminal 124 and a negative voltage (−) is applied to the first internal electrode terminal 121, the LED chips 100 to 400 that can be driven in alternating current are also provided. Since the four LED chips 100 to 400 emit light as described above, the varistors V10 and V20 connected in parallel with the LED chips 100 to 400 provide stable operation against ESD discharge and surge voltage. can do.

In the above embodiment, four LED chips are connected in series, but the present invention is not limited thereto, and a plurality of LED chips may be connected in parallel. In other words, the four LED chips are connected in series to drive at an AC power supply of 220V. However, the four LED chips may be connected in parallel to each other to drive 110V AC power. This fifth embodiment of the present invention will be described with reference to the drawings. In the following embodiments, descriptions overlapping with those of the first to fourth embodiments described above will be omitted.

13 and 14 illustrate a fifth embodiment of the present invention, wherein a light emitting device includes a plurality of LED chips 100 to 400 connected in parallel and a plurality of LED chips 100 to 400 connected in parallel. And first and second varistors V10 and V20 and first and second resistors R10 and R20 connected in series with the plurality of LED chips 100 to 400. This is almost the same as the case of the fourth embodiment, in which only the first LED chip 100 and the second LED chip 200 are connected in series between the second node N20 and the fourth node N40. In this connection, the third LED chip 300 and the fourth LED chip 400 are connected in series.

The light emitting device of this embodiment shown in FIG. 14 is almost the same as in the case of FIG. 12, but in this embodiment, the connection form of the first to fourth LED chips 100 to 400 is different.

In the light emitting device of the present invention, since a varistor connected in parallel with an LED chip is provided in a package, when the voltage applied to the LED chip suddenly increases, the varistor bypasses a voltage higher than the normal operating voltage to prevent ESD discharge or damage. Stable operation is possible even with surge voltage. This can improve the reliability and extend the life of the light emitting device.

Therefore, the present invention can simplify the manufacturing process and reduce the size of the light emitting device by using an LED chip to which a plurality of light emitting cells are connected. The light emitting cells in the LED chip are connected at the wafer level, so that the light source can be concentrated to increase the light emitting efficiency. By using the LED chip with the light emitting cells connected, it is possible to reduce the connection cost for the connection between the light emitting cells and to prevent defects that may occur during the connection, thereby reducing the defective rate when manufacturing the light emitting device using the LED chip. have.

Further, in the light emitting device of the present invention, by arranging varistors so as to be connected in parallel to the LED chips, the LED chips can be protected from surges due to electrostatic discharge or abnormal voltage. Thus, there is an advantage that can improve the life and reliability of the light emitting device. In addition, a varistor can be provided inside the LED package to reduce the need for separate circuit protection.

Claims (10)

A light emitting unit having an LED chip; Protection means connected in parallel with the light emitting portion to protect the light emitting portion from the occurrence of an abnormal abnormal voltage; LED light emitting device comprising a package surrounding the light emitting portion and the protection means. The method according to claim 1, And said protective means comprises a varistor or zener diode. The method according to claim 1 or 2, And said protection means is connected in parallel with one or more of said LED chips. The method according to claim 1 or 2, And a resistor connected in series with the light emitting unit. The method according to claim 4, The resistor is an LED light emitting device, characterized in that it comprises a resistor or PTC. The method according to claim 1 or 2, The light emitting unit further comprises a rectifying circuit electrically connected to the LED chip. The method according to claim 1 or 2, And said protective means is located in an adjacent region of the LED chip inside said package. The method according to claim 1 or 2, And a heat sink in the package. The method according to claim 8, The heat sink is LED light emitting device, characterized in that provided under the LED chip. The method according to claim 9, The protection means is mounted on the inside of the heat sink LED light emitting device.

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