JP5946311B2 - LED module - Google Patents

Description

  The present invention relates to an LED module in which other electronic components are mounted on a circuit board together with a plurality of LED elements.

  Lighting fixtures using LED elements have become widespread. In such a situation, the light source unit may be modularized in order to shorten the design time of lighting fixtures such as desk lamps and lamps. For example, FIG. 2 of Patent Document 1 shows an LED module in which a drive circuit is mounted on the same circuit board together with a plurality of LED chips (LED elements).

  FIG. 2 of Patent Document 1 is shown again in FIG. FIG. 6 is a cross-sectional view of an LED lamp using an IEC standard base (GX53 type). The LED module includes a circuit board 2, a driver circuit 4, and an LED 3 (LED element). The driver circuit 4 is mounted on the upper surface of the circuit board 2, and the LED 3 is mounted on the lower surface of the circuit board 2. This LED module is fitted into the housing of the base 1 and is held down by the light emitting surface cover case 5. When thinning is required, the LED 3 may be a COB (chip on board). The COB is a device in which a bare chip LED (hereinafter referred to as an LED die unless otherwise specified) is directly mounted on the circuit board 2.

JP 2007-157690 A (FIG. 2)

  In the LED module shown in FIG. 6, the drive circuit 4 and the LED 3 are integrated by disposing the drive circuit 4 on one surface of the circuit board 2 and the LED 3 on the other surface. Further, Patent Document 1 suggests that the LED 3 can be made thinner by using COB. However, if the LED die and the driver circuit can be arranged only on one surface of the circuit board, the thickness can be further reduced. In this case, since the mountable area becomes narrow, the driver circuit must also be made small. For example, if the driver circuit is made up of one resistor, stable operation is guaranteed against fluctuations in the power supply voltage. If the simplification is advanced so that it cannot be performed, sufficient performance may not be obtained.

  Therefore, the present invention has been made in view of the above problems, and in an LED module in which other electronic components are mounted on a circuit board together with a plurality of LED elements, the driver circuit is small and convenient and has sufficient performance. An object of the present invention is to provide an LED module that is easy to manufacture.

The LED module of the present invention is an LED module in which a plurality of LED elements and a driver circuit for driving the LED elements are mounted on a circuit board.
Before SL LED element forms a plurality of partial LED strings connected in series, further said portion LED string to form a LED strings connected in series,
The driver circuit includes a bridge rectifier circuit , a bypass circuit connected to a connection part between the partial LED strings, and a current limiting circuit connected to an end part of the LED string ,
The area for mounting the LED element is arranged around the area for mounting the driver circuit,
The bridge circuit consists of four diodes,
An AC connection terminal is provided in a region inside the wiring connecting the diodes,
The driver circuit other than the bridge circuit and the LED array are arranged in a region outside the wiring connecting the diodes .
The bypass circuit includes a first current input terminal, a second current input terminal, and a current output terminal, and the first current input terminal is connected to a connection portion of the partial LED array and is input from the second current input terminal. The current input from the first current input terminal may be limited by the current.

  In the LED module of the present invention, a driver circuit including a bridge rectifier circuit, a bypass circuit, and a current limiting circuit is disposed around the AC connection terminal, and an LED element is disposed around the driver circuit. An AC power source is connected to the AC connection terminal, and the LED row is lit with a full-wave rectified waveform generated from the AC power source by a bridge rectifier circuit. This LED row is formed by connecting LED elements in series, and can be divided into a plurality of partial LED rows. The first current input terminal of the bypass circuit is connected to the connection portion of the partial LED row. At this time, the current flowing through the LED string flows into the first current input terminal or the second current input terminal of the bypass circuit.

  The bridge rectifier circuit is composed of four diodes. The bypass circuit is configured to have only a first current input terminal, a second current input terminal, and a current output terminal for the outside. The current limiting circuit is configured to have only a current input terminal and a current output terminal for the outside. At this time, the bypass circuit limits the current input from the first current input terminal by the current input from the second current input terminal. By adopting such a configuration, the bypass circuit and the current limiting circuit need no power supply wiring, and further, as described above, the current flowing through the LED string flows into the first current input terminal or the second current input terminal of the bypass circuit. Circuit control wiring is also unnecessary. As a result, since the wiring of the driver circuit is reduced, the driver circuit can be built only by forming a wiring pattern on one surface of the circuit board, and the circuit board can be easily manufactured.

  Further, in the period when the voltage of the full-wave rectified waveform is low, a current flows from the partial LED row in the previous stage through the first current input terminal of the bypass circuit when viewed from the side where the full-wave rectified waveform is applied, The subsequent partial LED row is turned off. When the voltage of the full-wave rectified waveform becomes high and current also flows in the subsequent partial LED string, there is no current passing through the first current input terminal of the bypass circuit, and the subsequent partial LED string is combined with the previous partial LED string. Lights up efficiently. In addition, since the LED row can be kept lit for a relatively long period in one cycle of the full-wave rectified waveform, the luminance is improved and the flicker is reduced.

  The bypass circuit includes a depletion type FET and a resistor, the drain of the FET is connected to the first current input terminal, the source of the FET and one end of the resistor are connected to the second current input terminal, and the current The gate of the FET and the other end of the resistor may be connected to the output terminal.

  A first dam material and a second dam material, wherein the first dam material surrounds the LED row, the second dam material is disposed between the AC connection terminal and the driver circuit, and The region between the second dam materials may be filled with a covering member.

The LED element, the FET , the resistor, and the diode constituting the bridge rectifier circuit may be a bare chip.

  Of the partial LED strings, one partial LED string may surround the other partial LED strings in a ring shape.

  The LED element may be a chip size package LED.

  Of the partial LED strings, one partial LED string may annularly surround another partial LED string, and the one partial LED string may include a chip size package LED having a wide light distribution.

  In the LED module of the present invention, a driver circuit is arranged around the AC connection terminal, and an LED element is arranged around the driver circuit. Since the bypass circuit and the current limiting circuit included in the driver circuit do not require power supply wiring or control wiring, a driver circuit can be created simply by forming a wiring pattern on one surface of the circuit board, thereby facilitating circuit board manufacture. Since the bridge circuit is mounted, the LED element can be driven by the full-wave rectified waveform only by connecting an AC power supply, so that high convenience and efficient driving can be achieved. Furthermore, since the light is lit for a relatively long period in one cycle of the full-wave rectified waveform by the bypass circuit, effects such as improvement in luminance and reduction in flicker can be obtained. Furthermore, since a bypass circuit and a current limiting circuit are provided, a wide operating voltage range is ensured, and the operation is stable even if the voltage of the AC power supply fluctuates.

  As described above, the LED module of the present invention only needs to be connected to an AC power source. Even if the LED element is driven by a full-wave rectified waveform obtained from the AC power source, the non-lighting period is short and the circuit board wiring Since the pattern is simplified, the driver circuit is small in size, is convenient, has sufficient performance, and is easy to manufacture.

BRIEF DESCRIPTION OF THE DRAWINGS The external view of the LED module shown as 1st Embodiment of this invention. The top view of the state which remove | excluded the fluorescent resin from the LED module shown in FIG. The substantial circuit diagram of the LED module shown in FIG. The circuit diagram of the LED module shown in FIG. Sectional drawing of the LED element used by 2nd Embodiment of this invention. Sectional drawing of the LED module shown as a prior art example.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to FIGS. In the description of the drawings, the same or equivalent elements will be denoted by the same reference numerals, and redundant description will be omitted. For the sake of explanation, the scale of the members is changed as appropriate. Furthermore, the relationship with the invention specific matter described in the claims is described in parentheses. Since the LED element takes various forms, the LED element in a bare chip state cut out from the wafer is called an LED die, and the planar size is substantially equal to the LED die, and the LED element whose surface or side surface is covered with a resin or the like. Is called a chip size package LED.
(First embodiment)

  First, the external appearance of the LED module 100 will be described with reference to FIG. 1A and 1B are external views of the LED module 100, where FIG. 1A is a plan view and FIG. 1B is a front view. On the circuit board 111, a circular dam material 112 (first dam material) and a dam material 114 (second dam material) composed of a straight side extending in the vertical direction in the figure and a curved side existing in the upper and lower portions. ) A region between the dam material 112 and the dam material 114 is filled with a fluorescent resin 113 (covering member). There are AC connection terminals 115 and 117 in a region surrounded by the dam material 114, and the AC connection terminals 115 and 117 are provided with through holes 116 and 118, respectively. Although not shown, the back surface of the circuit board 111 has two back surface AC connection terminals for receiving power supply from the lighting fixture, and the back surface AC connection terminals are connected to the AC connection terminals 115 and 117 through the through holes 116 and 118. Connected.

  Next, the arrangement of the electronic components of the LED module 100 will be described with reference to FIG. FIG. 2 is a plan view showing a state where the fluorescent resin 113 is removed from the LED module 100 shown in FIG. The wiring pattern existing below the dam material 114 is also indicated by a solid line.

In FIG. 2, there are diodes 301, 302, 303, 304, FETs 324, 344, and resistors 325, 345 around the dam material 114. Diodes 301, 302,
303 and 304, FETs 324 and 344, and resistors 325 and 345 constitute a driver circuit. A region where these electronic components are mounted is surrounded by 45 LED dies 21 (hereinafter, individual LED dies are distinguished by adding a suffix if necessary) with a double ring. These LED dies 21 are connected in series to form one LED row, and the outer ring and the inner ring of this LED row become partial LED rows (partial LED rows 310 and 330 shown in FIG. 4), respectively. Further, there is a circular dam material 112 outside the region where the LED die 21 is mounted.

  The diodes 301, 302, 303, 304 and the two FETs 324, 344 are bare chips, and are die-bonded on the wiring pattern with a conductive paste. At this time, the bottom surfaces of the diodes 301, 302, 303, and 304 are anodes, and the bottom surfaces of the FETs 324 and 344 are drains. The resistors 325 and 355 and the LED die 21 are also bare chips and are die-bonded on the wiring pattern, but the bottom surface is insulated. Note that there is an island-like wiring pattern (state that is isolated and not connected to other wiring patterns) for die bonding at the bottom of the LED die 21, but is not shown. Except for the diodes 301, 302, 303, 304 and the bottoms of the FETs 324, 344, the diodes 301, 302, 303, 304, FETs 324, 344, and resistors 325, 345 are connected to the wiring pattern by wires 22. Only the source of the FET 344 and the resistor 345 are directly connected by the wire 22. The LED die 21 is also connected to the wiring pattern or another LED die 21 with a wire 22. In FIG. 2, many LED dies 21 are directly connected by wires 22, but when the distance between the LED dies 21 is long, an island-like relay wiring pattern is provided to increase the length of the wires 22. You may adjust it.

  The LED die 21 is 500 μm × 290 μm, the FETs 324 and 344 are 1.5 mm × 1.5 mm, and the resistors 325 and 345 are 500 μm × 500 μm. The circuit board 111 was made of alumina in consideration of thermal conductivity and reflectance. In the wiring pattern, Ni, Pd, and Au are laminated on Ag. The dam materials 112 and 114 are made of silicone resin and have a thickness of 0.7 to 1.0 mm and a height of 0.5 to 0.7 mm. The fluorescent resin 113 shown in FIG. 1 is a silicone resin containing a phosphor and has a thickness of about 400 to 800 μm. Even when the coating material of the FETs 324 and 344 is the fluorescent resin 113, no malfunction occurred due to light.

  Next, a method for manufacturing the LED module 100 will be described with reference to FIGS. First, the LED die 21, the diodes 301 to 304, the FETs 324 and 344, and the resistors 325 and 345 are die-bonded on the circuit board 111, and then wire-bonded. Next, the dam materials 112 and 114 before curing are arranged by a dispenser, and the dam materials 112 and 114 are cured at about 150 ° C. Finally, a fluorescent resin 113 is applied between the dam materials 112 and 114 with a dispenser to cover the LED die 21 and other electronic components. The sintering temperature of the fluorescent resin 113 is about 150 ° C.

  Next, the connection state of the LED module 100 will be described with reference to FIG. FIG. 3 is a substantial circuit diagram of the LED module 100 shown in FIG. 2, and is drawn so that the relative positional relationship between the electronic component shown in FIG. 2 and the electronic component shown in FIG. The LED dies 21 are connected in series, and this LED row starts from the LED die 21a, passes through the LED dies 21b and 21c, and ends at the LED die 21d. The mounting part of the part (partial LED row 310 shown in FIG. 4) from the LED die 21a to the LED die 21b is along the outer periphery. A portion (partial LED array 330 shown in FIG. 4) from the LED die 21c to the LED die 21d is arranged inside the partial LED array 310 in an annular shape. The anode of the LED die 21a is connected to the cathodes of the diodes 302 and 304. The cathode of the LED die 21b is connected to the drain of the FET 324 together with the anode of the LED die 21c. The cathode of the LED die 21d is connected to the drain of the FET 344.

  The anodes of the diodes 301 and 303 are connected to the resistor 325 and the gate of the FET 324. A connection portion between the diode 301 and the diode 302 and a connection portion between the diode 303 and the diode 304 are connected to the AC connection terminals 115 and 117, respectively. The source of the FET 344 is connected to one end of the resistor 345, the gate of the FET 344 is connected to the other end of the resistor 345, and is connected to the sources of the resistor 325 and the FET 324.

  Next, the operation of the LED module 100 will be described with reference to FIG. FIG. 4 is a circuit diagram of the LED module 100 and peripheral circuits. The circuit diagram of FIG. 3 and the circuit diagram of the LED module 100 shown in FIG. 4 are equivalent, and the same reference numerals are used for the respective electronic components. The LED module 100 includes a bridge rectifier circuit 305, a partial LED array 310, a partial LED array 330, a bypass circuit 320, and a current limiting circuit 340, and a commercial AC power supply 306 is also added in FIG. The driver circuit is a portion obtained by removing the partial LED rows 310 and 330 from the LED module 100. The bridge rectifier circuit 305 includes four diodes 301, 302, 303, and 304. A terminal A is an output terminal for a full-wave rectified waveform, and a terminal B is a terminal for supplying a reference voltage. The commercial AC power supply 306 is connected to the input terminals (AC connection terminals 115 and 117) of the bridge rectifier circuit 305.

  The LED row of the entire LED module 100 is a partial LED row 310 and a partial LED row 330 connected in series. In the partial LED array 310, a large number of LED dies 21 (see FIG. 3) including LED dies 21a and 21b are connected in series. Similarly, a large number of LED dies 21 including LED dies 21c and 21d are also included in the partial LED array 330. (See FIG. 3) are connected in series. The anode of the partial LED string 310 is connected to the A terminal of the bridge rectifier circuit 305. The connection part of the partial LED strings 310 and 330 is connected to the current input terminal 321 (first current input terminal) of the bypass circuit 320. The cathode of the partial LED row 330 is connected to the current input terminal 341 of the current limiting circuit 340.

  The bypass circuit 320 includes a current input terminal 321 (first current input terminal), a current input terminal 322 (second current input terminal), and a current output terminal 323. The current input terminal 322 is connected to the current output terminal 343 of the current limiting circuit 340. The current output terminal 323 is connected to the B terminal of the bridge rectifier circuit 305. The bypass circuit 320 includes a depletion type FET 324 and a resistor 325, the drain of the FET 324 is connected to the current input terminal 321, the source of the FET 324 and one end of the resistor 325 are connected to the current input terminal 322, and the FET 324 is connected to the current output terminal 323. And the other end of the resistor 325 are connected. In the bypass circuit 320, the current flowing from the current input terminal 321 is limited by the current flowing from the current input terminal 322.

  The current limiting circuit 340 has substantially the same circuit configuration as the bypass circuit 320, and the only difference is that there is no equivalent to the current input terminal 322 of the bypass circuit 320. The connection of the FET 344 and the resistor 345 is also equal to the bypass circuit 320. Since the forward voltage drop amount of the LED die 21 is about 3V, the threshold value of the partial LED array 310 is about 75V, the threshold value of the partial LED array 330 is about 60V, and the LED module 100 has a commercial AC power supply 306 having an effective value of 120V. It corresponds to. The resistor 345 has a smaller value than the resistor 325, and the ratio of the resistance values of the resistor 345 and the resistor 325 is 1: 2.

  Next, the lighting state of the LED module 100 will be described with reference to FIG. When the voltage of the full-wave rectified waveform rises and exceeds the threshold value of the partial LED string 310, a current flows through the partial LED string 310 and the bypass circuit 320, and the partial LED string 310 is lit. At this time, feedback is applied from the resistor 325 to the source of the FET 324, and the bypass circuit 320 operates at a constant current.

  Further, when the voltage of the full-wave rectified waveform rises and becomes larger than the sum of the threshold value of the partial LED string 310 and the threshold value of the partial LED string 330, a current starts to flow through the partial LED string 330 and the current limiting circuit 340. When the current input to the current input terminal 322 exceeds a predetermined value, the FET 324 is cut off because the source voltage rises and the voltage between the source and the gate spreads. At this time, feedback is applied from the resistor 345 to the FET 344, and the current limiting circuit 340 operates at a constant current. In this way, the partial LED row 310 and the partial LED row 330 are turned on. In the period in which the voltage of the full-wave rectified waveform falls, the reverse process of the period in which the voltage of the full-wave rectified waveform rises is followed.

  In the LED module 100, the partial LED array 310 and the partial LED array 330 are arranged in an annular shape (see FIG. 2). Distribution is obtained.

  In the LED module 100, the bypass circuit 320 only includes a depletion type FET 324 and a resistor 325. Further, since the current flowing through the partial LED array 330 is input to the second current input terminal 322 of the bypass circuit 320 and the current flowing from the first current input terminal 321 is limited, the bypass circuit 320 restricts the power supply wiring and the control. There is no wiring. Therefore, a circuit diagram can be drawn without crossing the wiring (see FIG. 3). The same applies to the current limiting circuit 340. This indicates that each electronic component can be connected only by the wiring pattern on the surface of the circuit board 111 and the wire 22 (see FIG. 2). That is, the circuit board 111 (see FIGS. 1 and 2) is easy to manufacture because no through-hole is required except for the through-holes 116 and 118 (see FIG. 1) connected to the AC connection terminals 115 and 117.

  In FIG. 4, the bypass circuit 320 includes an FET 324 and a resistor 325. Similarly, the current limiting circuit 340 includes an FET 344 and a resistor 345. As is well known, the current limiting circuit can also be composed of two resistors, an enhancement type FET, and an NPN bipolar type transistor. In the current limiting circuit, a resistor and a drain of the FET are connected to a current input terminal (first current input terminal), and the other end of the resistor is connected to a gate of the FET and a collector of the transistor. The other resistor, the source of the FET, and the base of the transistor are connected, and the other end of the resistor and the emitter of the transistor are connected to the current output terminal. At this time, if the wiring connected to the base of the transistor or the like is the second current input terminal, a bypass circuit that limits the current input to the first current input terminal by the current input to the second current input terminal can be configured.

In FIG. 4, the block composed of the partial LED string 310 and the bypass circuit 320 is similar to the block composed of the partial LED string 330 and the current limiting circuit 340. That is, it is possible to cascade-connect blocks composed of the partial LED string 310 and the bypass circuit 320, and to make the bypass circuit included in the final block a current limiting circuit. At this time as well, the circuit diagram can be drawn without crossing the wires as described above, so that a through hole is not required in the circuit board except for the AC connection terminal. In addition, it is necessary to adjust the number and resistance value of the LED element contained in a partial LED row by use conditions. In this way, if the block composed of the partial LED array and the bypass circuit is multistaged in the LED module, the change in the circuit current can be finely controlled, so that the circuit current waveform approaches a sine wave, and the power factor and distortion rate are improved.
(Second Embodiment)

In the LED module 100 shown as the first embodiment, the LED die 21 is die-bonded to the circuit board 111 and connected to the wiring pattern or another LED die by the wire 22. However, the LED die mounting method is not limited to die bonding and wire bonding, and the LED die may be flip-chip mounted. In this case, since the LED dies are connected by the wiring pattern, a connection wire is not necessary. For this reason, the shadow of the wire disappears and the light emission efficiency of the LED module is improved. In the LED module 100, the FETs 324 and 344 and the resistors 325 and 345 are also mounted by die bonding and wire bonding, so that the size is reduced and the mounting method of the LED die 21 is shared. However, FETs and resistors may be surface mount chip components. Similarly, the LED element is not limited to the LED die, and may be a chip component for surface mounting. Therefore, referring to FIG. 4, an LED module using a surface mounting LED element (referred to as chip size package LED, chip size package is also referred to as CSP) having the same size as the LED die will be described as a second embodiment.

  FIG. 5 is a sectional view of chip size packages LEDs 501 and 502 (LED elements) used in the LED module of the second embodiment of the present invention. In the chip size package LED 501 shown in (a), the side surface of the LED die 511 is covered with a reflective resin 504 (covering member), and the upper surface of the LED die 511 is covered with a fluorescent resin 503 (covering member). In the chip size package LED 501 shown in (b), the fluorescent resin 505 (covering member) covers the side surface and the upper surface of the LED die 511. The LED die 511 includes projecting electrodes 512 and 513 on the lower surface, and the projecting electrodes 512 and 513 serve as an anode and a cathode, respectively. The LED die 511 has a transparent insulating substrate made of sapphire or the like with a thickness of 80 to 120 μm, and a semiconductor layer including a light emitting layer is formed on the lower surface thereof. The protruding electrodes 512 and 513 are connected to the semiconductor layer through through holes of an insulating film that covers the semiconductor layer. In addition, the size and position of the protruding electrodes 512 and 513 are adjusted by a well-known method in a semiconductor process such as an interlayer insulating film or an interlayer wiring so as to facilitate flip-chip mounting.

  The fluorescent resins 503 and 505 are obtained by kneading and curing a phosphor in a silicone resin and have a thickness of about 100 μm. The reflective resin 504 is also obtained by kneading and curing reflective part particles such as alumina and titanium oxide in a silicone resin, and has a thickness of about 100 μm. As a result, the chip size package LED 501 has a light distribution distribution only in the upward direction, whereas the chip size package LED 502 has a wide light distribution distribution because it also emits light from the side surface.

  The LED module (not shown) in the second embodiment is the same circuit as the LED module 100 in the first embodiment, and chip size packages LEDs 501 and 502 are arranged instead of the LED die 21 in FIG. The wiring pattern is for flip chip mounting, and the chip size packages LED501 and 502 are connected to the wiring pattern by solder reflow. At this time, in the outer partial LED array 310 including the LED dies 21a and 21b, the LED die 21 is replaced with a chip size package LED 502 (or a mixture of the chip size package LED 501 and the chip size package LED 502), and includes the LED dies 21c and 21d. In the inner partial LED array 330, the LED die 21 may be replaced with a chip size package LED501. If it does in this way, the fall of luminous efficiency can be prevented, expanding the light distribution of an LED module. Further, the LED module according to the second embodiment of the LED module 100 of FIG. 2 does not require the dam material 112 in the LED module 100, and the dam material 114 is also unnecessary by using a diode, FET, and resistor for surface mounting. At the same time, the fluorescent resin 113 (see FIG. 1) becomes unnecessary.

100 ... LED module,
111 ... circuit board,
112 ... Dam material (first dam material),
113,503,505 ... fluorescent resin (coating member),
114 ... Dam material (second dam material),
115, 117 ... AC connection terminal,
116, 118 ... through hole,
21, 21a-d ... LED die (LED element),
22 ... Wire,
301, 302, 303, 304 ... diodes,
305: Bridge rectifier circuit,
306 ... Commercial AC power supply,
310, 330 ... Partial LED row,
320: Bypass circuit,
321 ... Current input terminal (first current input terminal),
322 ... Current input terminal (second current input terminal),
323, 343 ... current output terminals,
324, 344 ... FET,
325,345 ... resistance,
340 ... current limiting circuit,
341 ... Current input terminal,
501 502: Chip size package LED (LED element),
504: Reflective resin (coating member),
511 ... LED die,
512, 513... Projection electrodes.

Claims (6)

In an LED module in which a plurality of LED elements and a driver circuit for driving the LED elements are mounted on a circuit board,
The LED elements are connected in series to form a plurality of partial LED rows, and the partial LED rows are connected in series to form an LED row,
The driver circuit includes a bridge rectifier circuit, a bypass circuit connected to a connection part between the partial LED strings, and a current limiting circuit connected to an end part of the LED string,
The area for mounting the LED element is arranged around the area for mounting the driver circuit,
The bridge rectifier circuit is composed of four diodes,
An AC connection terminal is provided in a region inside the wiring connecting the diodes,
The driver circuit other than the bridge circuit and the LED row are arranged in a region outside the wiring connecting the diodes,
The bypass circuit includes a first current input terminal, a second current input terminal, and a current output terminal, and the first current input terminal is connected to a connection portion of the partial LED array and is input from the second current input terminal. The current input from the first current input terminal is limited by the current ,
The bypass circuit includes a depletion type FET and a resistor, the drain of the FET is connected to the first current input terminal, the source of the FET and one end of the resistor are connected to the second current input terminal, and the current The LED module , wherein the FET gate and the other end of the resistor are connected to an output terminal . In an LED module in which a plurality of LED elements and a driver circuit for driving the LED elements are mounted on a circuit board,
The LED elements are connected in series to form a plurality of partial LED rows, and the partial LED rows are connected in series to form an LED row,
The driver circuit includes a bridge rectifier circuit, a bypass circuit connected to a connection part between the partial LED strings, and a current limiting circuit connected to an end part of the LED string,
The area for mounting the LED element is arranged around the area for mounting the driver circuit,
The bridge rectifier circuit is composed of four diodes,
An AC connection terminal is provided in a region inside the wiring connecting the diodes,
The driver circuit other than the bridge circuit and the LED row are arranged in a region outside the wiring connecting the diodes,
The bypass circuit includes a first current input terminal, a second current input terminal, and a current output terminal, and the first current input terminal is connected to a connection portion of the partial LED array and is input from the second current input terminal. The current input from the first current input terminal is limited by the current ,
A first dam material and a second dam material, wherein the first dam material surrounds the LED row, the second dam material is disposed between the AC connection terminal and the driver circuit, and An LED module, wherein a region between the second dam materials is filled with a covering member . 2. The LED module according to claim 1 , wherein the LED element, the FET, the resistor, and the diode constituting the bridge rectifier circuit are bare chips. LED module according to any one of claims 1 to 3 in which one of the partial LED string is equal to or surrounding the other parts LED string to the annular among the partial LED string. The LED module according to claim 1, wherein the LED element is a chip size package LED. Said portion LED first part LED columns of the column surrounds the other partial LED row annularly in claim 5, characterized in that it contains a wide chip size package LED of light distribution to the one portion LED column The LED module described.

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