JP5858854B2 - 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. 8 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. 8, 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 composed 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, wherein the LED elements are connected in series to form a plurality of partial LED arrays, The partial LED strings are connected in series to form an LED string, and the driver circuit includes a bridge rectifier circuit, a bypass circuit connected to the connection between the partial LED strings, and a current limit connected to the end of the LED string. The bridge rectifier circuit is composed of four diodes, and includes an AC connection terminal in a region outside the wiring connecting the diodes. A driver circuit other than the bridge circuit and the LED array are arranged in an area inside the wiring connecting the LED , and the bypass The circuit includes a first current input terminal, a second current input terminal, and a current output terminal, wherein the first current input terminal is connected to a connection portion of the partial LED array, and current is input from the second current input terminal. The current input from the first current input terminal is limited, includes a depletion type FET and a resistor, the drain of the FET is connected to the first current input terminal, and the source of the FET is connected to the second current input terminal. One end of the resistor is connected, and the gate of the FET and the other end of the resistor are connected to the current output terminal .

  In the LED module of the present invention, the LED element is mounted at the center of the circuit board. The driver circuit includes a bridge rectifier circuit, a bypass circuit, and a current limiting circuit, and is arranged around a region where the LED element is mounted. Moreover, the LED module of this invention connects an alternating current power supply to the input terminal of a bridge rectifier circuit, and makes an LED row light by the full wave rectification waveform produced | generated from the 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. Similarly, 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 as viewed from the side where the full-wave rectified waveform is applied, and the partial LED row in the previous stage is lit. 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 region for mounting the LED element may be sandwiched between a region for mounting two of the four diodes included in the bridge rectifier circuit and a region for mounting the other two diodes.

The LED element, the FET, the resistor and the diode constituting the bridge rectifier circuit Ri bare der, region of mounting the LED element is surrounded by a dam member, a region mounting the FET, the resistor and the diode May be surrounded by the dam material and a dam material different from the dam material, and may be divided into two locations .

In the LED module of the present invention, 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 by simply forming a wiring pattern on one surface of the circuit board. Is easy to manufacture. Further, since a bridge circuit is mounted, it is only necessary to connect an AC power source, and the LED element can be driven by the full-wave rectified waveform obtained at this time, so that high convenience and efficient driving are 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. Further, since a current limiting circuit is provided in addition to the bypass circuit, a wide operating voltage range is secured, and the operation is stabilized even when 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 further the wiring of the circuit board 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. The circuit diagram of the LED module shown as 2nd Embodiment of this invention. The circuit diagram which materialized the circuit diagram of the LED module shown in FIG. The actual circuit diagram of the LED module shown as 3rd 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 has various mounting forms, the LED element in a bare chip state cut out from the wafer is referred to as an LED die.
(First embodiment)

  The LED module 100 shown as the first embodiment of the present invention will be described with reference to FIGS. 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, there are a circular dam material 112 and a rectangular dam material 114 with one side missing. A region inside the dam material 112 is filled with a fluorescent resin 113, and a region surrounded by the dam material 112 and the dam material 114 is filled with a fluorescent resin 115. In addition, the area | region enclosed with the dam material 112 and the dam material 114 exists in the upper and lower two places of a figure. The wiring pattern on the circuit board 111 is not shown.

  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 of the LED module 100 shown in FIG. 1 with the fluorescent resins 113 and 115 removed, and shows the area inside the dam materials 112 and 114. Note that the circuit board 111 and the wiring pattern on the circuit board 111 are not shown, and instead, the connection corresponding to the wiring pattern is indicated by a dotted line.

In FIG. 2, on the circuit board 111 (see FIG. 1), there are 48 LED dies 21 (hereinafter, individual LED dies are distinguished by adding a suffix if necessary) and four diodes 301 and 302. , 303, 304, two FETs 324, 344 (a depletion type FET in a bare chip state), and two resistors 325, 345 are mounted. The mounting area of the LED die 21 is substantially circular and is surrounded by a circular dam material 112. A region where the diodes 301 to 304, the FETs 324 and 344, and the resistors 325 and 345 are mounted is surrounded by the arc of the dam material 112 and the dam material 114. Note that the wiring pattern (not shown) of the circuit board 111 is formed only on the upper surface (front surface), and the circuit board 111 has no through holes.

  The diodes 301 to 304 and the FETs 324 and 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 to 304 are anodes, and the bottom surfaces of the FETs 324 and 344 are drains. The connection to the anode and drain at the bottom is indicated by the dotted lines abutting the diodes 301 to 304 and the FETs 324 and 344 in the figure. 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. There is an island-like wiring pattern (not shown) at the bottom of the LED die 21 for die bonding (in an isolated state and not connected to other wiring patterns). Except for the diodes 301 to 304 and the bottoms of the FETs 324 and 344, the diodes 301, 302, 303 and 304, the FETs 324 and 344, and the resistors 325 and 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 LED dies 21 are separated from each other, 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. The LED dies 21 are connected in series to form an LED array. This LED row starts with the LED die 21a, passes through the LED dies 21b, 21c, 21e, and 21f, and ends with the LED die 21d. The LED row is divided into a portion from the LED die 21a to the LED die 21b (partial LED row 310 shown in FIG. 4) and a portion from the LED die 21c to the LED die 21d (partial LED row 330 shown in FIG. 4). . Moreover, the partial LED row 330 is separated into a portion from the LED die 21c to the LED die 21e and a portion from the LED die 21f to the LED die 21d, and these two portions sandwich the partial LED row 310. 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 21e is connected to the anode of the LED die 21f. 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 23 and 24, 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.

  A circuit showing this connection state is shown in FIG. FIG. 3 is a substantial circuit diagram of the LED module 100 shown in FIG. 2. The electronic components shown in FIG. 2 and the electronic components shown in FIG. In addition, the direction of the LED die 21 is also clearly shown. In addition, the fact that the wiring does not intersect in FIG. 3 indicates that all the electronic components of the LED module 100 can be connected with the wiring pattern formed only on the surface of the circuit board 111 as described in the description of FIG. Yes.

  Next, functional blocks and operations 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 23 and 24) 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. The bypass circuit 320 limits the current flowing from the current input terminal 321 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 of the partial LED array 310 is about 72V, the threshold of the partial LED array 330 is about 72V, and the LED module 100 has a commercial AC power supply 306 with 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.

  As described above, the LED module 100 is mounted so that the LED die 21 included in the partial LED array 310 is sandwiched between the LED dies 21 included in the partial LED array 330 (see FIGS. 2 and 3). The symmetry axis of the light distribution in the low voltage phase of the rectified waveform coincides with the symmetry axis of the light distribution in the high voltage phase, so that a good light distribution can be obtained as a whole.

  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. The same applies to the current limiting circuit 340. Therefore, a circuit diagram can be drawn without crossing the wiring (see FIG. 3). 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) does not require a through hole and is easy to manufacture.

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.
(Second Embodiment)

  As shown in FIG. 4, in the LED module 100 of the first embodiment, the block composed of the partial LED array 310 and the bypass circuit 320 is similar to the block composed of the partial LED array 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, the circuit diagram can be drawn without crossing the wiring. Therefore, an LED module 500 according to a second embodiment of the present invention in which a block including a partial LED array and a bypass circuit is multistaged will be described with reference to FIGS. The appearance of the LED module 500 is substantially equal to the appearance of the LED module 100 shown in FIG.

The circuit of the LED module 500 will be described with reference to FIG. FIG. 5 is a circuit diagram of the LED module 500, which is functionally drawn. The LED module 500 includes a bridge rectifier circuit 305, partial LED strings 501, 502, 503, 504, and 505, and a bypass circuit and a current limiting circuit. AC connection terminals 531 and 532 are connected to the diode bridge circuit. The bypass circuit has the same circuit configuration as the bypass circuit 320 shown in FIG. 4. In FIG. 5, the FET 511 and the resistor 521, the FET 512 and the resistor 522, the FET 513 and the resistor 523, and the FET 514 and the resistor 524 are combined. , Corresponds. Similarly, the current limiting circuit corresponds to a set of FET 515 and resistor 525. It should be noted that the number of LED dies and the resistance value included in the partial LED rows 501 to 505 need to be adjusted according to use conditions. For example, the ratio of the resistors 521, 522, 523, 524, 525 is 8: 7: 6: 5: 4. When a block composed of partial LED arrays and bypass circuits is multi-staged like the LED module 500, the circuit current waveform approaches a sine wave and the power factor and distortion rate are improved because the change in circuit current can be finely controlled.

Next, FIG. 6 shows that the circuit of the LED module 500 shown in FIG. 5 can be drawn without crossing the wiring even if the LED row is arranged in the center. FIG. 6 is a circuit diagram which materializes the circuit diagram of the LED module 500 shown in FIG. 6, diodes 301 and 302 included in the bridge rectifier circuit 305 (see FIG. 5) are on the upper side of the figure, and diodes 303 and 304 are on the lower side of the figure. That is, in FIG. 6, referring to FIG. 1A, the FETs 511 and 512 and the resistors 521 and 522 together with the diodes 301 and 302 are mounted in the upper region surrounded by the dam materials 112 and 114. 514 and 515 and resistors 523 and 524 and 525 are mounted in the lower region surrounded by the dam materials 112 and 114. The partial LEDs 501 to 505 are mounted in a region surrounded by the dam material 112. The AC connection terminals 531 and 532 are disposed on the upper side and the lower side of the circuit board 111 in FIG.
(Third embodiment)

  In the LED module 500 shown in the second embodiment, the AC connection terminals 531 and 532 are on one side and the other side of the circuit board 111, respectively. However, there are cases where it is desired to arrange two AC connection terminals on one side of the circuit board 111. Therefore, an LED module 700 including two AC connection terminals 731 and 732 on one side of the circuit board 111 will be described as a third embodiment of the present invention with reference to FIG. The circuit of the LED module 700 is the same as the circuit of the LED module 500 shown in FIG.

  FIG. 7 shows a situation in which the AC connection terminals 731 and 732 can be arranged on one side in the circuit of the LED module 700. FIG. 7 is a circuit diagram showing an actual circuit diagram of the LED module 700. In FIG. 7, diodes 301 to 304 included in the bridge rectifier circuit 305 (see FIG. 5) are on the upper side of the drawing. That is, in FIG. 7, referring to FIG. 1A, the FETs 511 and 512 and the resistors 521 and 522 together with the diodes 301 to 304 are mounted in the upper region surrounded by the dam materials 112 and 114. 514 and 515 and resistors 523 and 524 and 525 are mounted in the lower region surrounded by the dam materials 112 and 114. The partial LEDs 501 to 505 are mounted in a region surrounded by the dam material 112. The AC connection terminals 531 and 532 are arranged on the sides of the circuit board 111 in FIG.

  What is characteristic in the circuit diagram of FIG. 7 is that a wiring 601 (indicated by a dotted line) connecting the cathode of the diode 302 and the cathode of the diode 304 intersects with another wiring. In the actual circuit board 111 (see FIG. 1), the wiring 601 is the wire 22 (see FIG. 2), and the other wiring crossing the wiring 601 is a wiring pattern formed on the circuit board 111. That is, if the wire 22 is used, there is a case where a short circuit can be avoided at the intersection of the wirings on the circuit diagram.

  In the LED modules 100, 500, and 700 shown in the first to third embodiments, the LED die 21 is die-bonded to the circuit board 111 and connected to a wiring pattern or another LED die 21 with a 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. Further, it may be an LED chip for surface mounting. In particular, the LED module does not increase in size if the planar size of the package is a chip size package (also referred to as CSP) that is substantially equal to the LED die.

  In the LED modules 100, 500, and 700, the FETs 324, 344, 511 to 515 and the resistors 325, 345, and 521 to 525 are also mounted by die bonding and wire bonding to reduce the size and to share the LED die 21 mounting method. It was. However, although the wiring pattern cannot be jumped by the wire, the FET or the resistor may be a chip component for surface mounting as long as the components are arranged as shown in FIG.

100, 500, 700 ... LED module,
111 ... circuit board,
112, 114 ... Dam material,
113, 115 ... fluorescent resin,
21, 21 a to g ... LED die (LED element),
22,601 ... wire,
23, 24, 531, 532, 731, 732 ... AC connection terminals,
301, 302, 303, 304 ... diodes,
305: Bridge rectifier circuit,
306 ... Commercial AC power supply,
310, 330, 501-505 ... 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, 511 to 515 ... FET,
325, 345, 521-525 ... resistance,
340 ... current limiting circuit,
341: Current input terminal.

Claims (3)

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, around the area where the LED element is mounted. Arranged,
The bridge rectifier circuit is composed of four diodes,
An AC connection terminal is provided in a region outside the wiring connecting the diodes,
The driver circuit other than the bridge circuit and the LED row are arranged in a region inside 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, includes a depletion type FET and a resistor, the drain of the FET is connected to the first current input terminal, and the FET current is connected to the second current input terminal. An LED module , wherein a source and one end of the resistor are connected, and a gate of the FET and the other end of the resistor are connected to the current output terminal . The region for mounting the LED element is sandwiched between a region for mounting two diodes out of four diodes included in the bridge rectifier circuit and a region for mounting the other two diodes. The LED module according to claim 1 . The LED element, the FET, the resistor, and the diode constituting the bridge rectifier circuit are bare chips, a region for mounting the LED element is surrounded by a dam material, and a region for mounting the FET, the resistor, and the diode is LED module according to claim 1 or 2, wherein the dam member is surrounded by the dam member different from the dam member, characterized in that it is divided into two.

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