JP2013175692A - Led driver module and led bulb - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an LED driver module for which the space is saved and which is made small-sized and lightweight, and an LED bulb employing the same.SOLUTION: An LED driver module 10 is provided which comprises a protection circuit 11 which protects post-stage circuit parts from an input voltage, a rectifier circuit 12 which rectifies the input voltage inputted via the protection circuit 11, a filter circuit 13 which cancels a noise component from the input voltage rectified by the rectifier circuit 12, a voltage comparator 14 which compares the input voltage from which the noise component has been canceled by the filter circuit 13 with a threshold value, and a switch 15 which switches LED block parts B1, B2 to be power feeding targets in an LED module 20 that is a load, in accordance with a comparison result of the voltage comparator 14, and an LED bulb 1 employing the same is also provided.

Description

  The present invention relates to an LED (Light Emitting Diode) driver module and an LED bulb, and more particularly to an LED driver module reduced in size and weight and an LED bulb using the same.

  In recent years, power-saving and long-life LED bulbs have begun to spread rapidly. As an example of the prior art, Patent Literature 1 and Patent Literature 2 can be cited.

JP2011-198489A Japanese Unexamined Patent Publication No. 2011-159637

  By the way, the larger the number of LED elements mounted on the LED bulb, the larger the capacity of the electrolytic capacitor is required. That is, the larger the number of LED elements connected in series, the longer the time region in which the electric charge must be retained by the electrolytic capacitor, and thus a larger capacity is required. In addition, the larger the number of LED elements connected in parallel, the greater the amount of charge that must be protected from the electrolytic capacitor.

  However, an LED driver module incorporated in a small-sized (for example, E17 type) LED bulb must mount a large number of elements on a printed circuit board having a small area that can be accommodated in the LED bulb. Therefore, it is difficult to mount a large volume electrolytic capacitor.

  An object of the present invention is to provide an LED driver module that is space-saving, reduced in size and weight, and an LED bulb using the LED driver module.

  According to an aspect of the present invention, a protection unit that protects a subsequent circuit unit from an input voltage, a rectification unit that rectifies an input voltage input through the protection unit, and an input voltage rectified by the rectification unit A filter unit that removes a noise component from the voltage, a voltage comparison unit that compares an input voltage from which the noise component has been removed by the filter unit with a threshold value, and an LED module that is a load according to a comparison result of the voltage comparison unit There is provided an LED driver module including a switch unit that switches an LED block unit to be fed.

  According to another aspect of the present invention, a protection unit that protects a subsequent circuit unit from an input voltage, a rectification unit that rectifies an input voltage that is input via the protection unit, and a rectification unit that performs rectification by the rectification unit. A filter unit that removes noise components from the input voltage, a voltage comparison unit that compares the input voltage from which the noise components have been removed by the filter unit with a threshold, and an LED that is a load according to the comparison result of the voltage comparison unit Among the modules, an LED driver module including a switch unit that switches an LED block unit to be fed, an LED module that is fed from the LED driver module, a case in which the LED driver module and the LED module are mounted, An LED bulb including a light-transmitting cover that covers the LED module is provided.

  According to the present invention, it is possible to provide an LED driver module that is space-saving and reduced in size and weight, and an LED bulb that uses the LED driver module.

The typical block block diagram which shows the structural example of the LED bulb which concerns on 1st Embodiment. The typical block block diagram which shows more specifically the structural example of the LED bulb which concerns on 1st Embodiment. The flowchart figure which shows the operation example of the LED driver module which concerns on 1st Embodiment. It is a graph which shows the waveform of the LED driver module which concerns on 1st Embodiment, Comprising: (a) Input voltage waveform figure, (b) Output voltage waveform figure, (c) Output current waveform figure. The typical front perspective view which shows the structural example of the LED bulb which concerns on 1st Embodiment. The typical circuit block block diagram which shows the structural example of the LED driver module which concerns on 1st Embodiment. It is a typical top view showing the example of composition of the printed circuit board concerning a 1st embodiment, and (a) a schematic plan view of the surface and (b) a schematic plan view of the back. It is a schematic plan view which shows the structural example of the conventional printed circuit board, Comprising: (a) Typical top view of surface, (b) Typical top view of back surface. The typical circuit block block diagram which shows the structural example of the LED module which concerns on 1st Embodiment. The typical circuit block block diagram which shows the structural example of the other LED module which concerns on 1st Embodiment. The typical top view which shows the structural example of the alumina substrate which concerns on 1st Embodiment. The typical top view which shows the structural example of the conventional alumina substrate. The typical cross-section structure example of the LED module which concerns on 1st Embodiment. It is a figure for demonstrating the threshold value which concerns on 2nd Embodiment, Comprising: (a) The graph which shows the relationship between the input voltage from which the noise component was removed, and a threshold value, (b) The switch mounted in an LED driver module The typical block block diagram which shows the relationship between a threshold value. The typical block block diagram which shows the structural example of the LED bulb which concerns on 2nd Embodiment. The typical block block diagram which shows more specifically the structural example of the LED bulb which concerns on 2nd Embodiment. The flowchart figure which shows the operation example of the LED driver module which concerns on 2nd Embodiment. The typical circuit block block diagram which shows the structural example of the LED driver module which concerns on 3rd Embodiment. It is a schematic plan view which shows the structural example of the printed circuit board concerning 3rd Embodiment, Comprising: (a) Typical top view of surface, (b) Typical top view of back surface. It is a figure for demonstrating the notch formed in the printed circuit board which concerns on 3rd Embodiment, Comprising: (a) Typical side view when notch is not formed, (b) Notch The typical side view when it is formed. It is a schematic plan view which shows the example of a structure of the other printed circuit board concerning 3rd Embodiment, Comprising: (a) Typical top view of surface, (b) Typical top view of back surface. FIG. 10 is a diagram for explaining notches formed in a printed circuit board according to a third embodiment, and (a) a diagram for explaining notches formed in an edge near the center; FIG. 4 is a diagram for explaining a notch formed outside the input terminal. The typical circuit block block diagram which shows the structural example of the LED driver module which concerns on 4th Embodiment. It is a schematic plan view which shows the structural example of the printed circuit board which concerns on 4th Embodiment, Comprising: (a) Typical top view of surface, (b) Typical top view of back surface.

  Next, embodiments of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic, and the relationship between the thickness of each component and the planar dimensions, the ratio of the thickness of each layer, and the like are different from the actual ones. Therefore, specific thicknesses and dimensions should be determined in consideration of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.

  Further, the embodiments described below exemplify apparatuses and methods for embodying the technical idea of the present invention, and the embodiments of the present invention include the material, shape, and structure of each component. The arrangement is not specified below. Various modifications can be made to the embodiment of the present invention within the scope of the claims.

[First Embodiment]
Hereinafter, the first embodiment will be described with reference to FIGS.

  The LED bulb 1 according to the first embodiment includes an LED driver module 10, an LED module 20 that is fed from the LED driver module 10, a case 30 on which the LED driver module 10 and the LED module 20 are mounted, and an LED module. The LED driver module 10 includes a protection circuit 11 that protects a subsequent circuit portion from an input voltage, and a rectifier circuit 12 that rectifies the input voltage input via the protection circuit 11. And a filter circuit 13 for removing a noise component from the input voltage rectified by the rectifier circuit 12, a voltage comparator 14 for comparing the input voltage from which the noise component has been removed by the filter circuit 13 with a threshold value, and a comparison result of the voltage comparator 14 Depending on the power supply, the LED module 20 that is a load And a switch 15 to switch the LED block portion B1, B2 of the elephants.

  Further, the switch 15 may switch the LED block portions B1 and B2 to be fed so that there is no output area of 5% or less when the peak of the output current is 100%.

  The LED module 20 may include a plurality of LED elements connected in series of n in series and m in number, and the switch 15 may switch the number of LED elements in series according to the comparison result of the voltage comparator 14.

  When the input voltage is equal to or higher than the threshold value, the step-down switching DC / DC circuit 16 supplies power to all the LED block units B1 and B2. Power may be supplied to B2.

  Further, the input voltage may be compared in order from the highest value of n threshold values, and when the input voltage is equal to or higher than the kth compared threshold value, the power supply limiter 17 may supply power to the LED block units Bk to Bn.

  Further, the LED bulb 1 may be a mini-krypton type.

  Moreover, the LED bulb 1 may have an outer diameter of 35 mm and a total length of 67 mm or less.

  The size of the printed circuit board 10a forming the LED driver module 10 may be 28.0 mm × 11.5 mm or less.

  The LED module 20 may have a COB (Chip on Board) structure. The COB structure refers to a structure in which a bare chip (LED element D itself) is directly mounted on a wiring pattern on the alumina substrate 21a and wire-bonded to be resin-sealed.

(overall structure)
FIG. 1 is a schematic block diagram illustrating a configuration example of the LED bulb 1 according to the first embodiment. As shown in this figure, the LED bulb 1 includes an LED driver module 10 and an LED module 20.

  The LED module 20 is a light source of the LED bulb 1 that emits light of daylight color (color temperature of about 5000 K) or light bulb color (color temperature of about 3000 K), and includes a plurality of LED elements (VF) connected in series of n pieces in series and m pieces. For example, 3V). Here, it is assumed that two LED block portions B1 and B2 to be fed are provided.

  When an AC voltage (for example, AC 100 V ± 10%) is input from the commercial AC power source 2, the LED driver module 10 converts the AC voltage into a DC LED driving voltage (for example, DC 32 V) and supplies the converted voltage to the LED module 20. Specifically, the protection circuit 11, the rectifier circuit 12, the filter circuit 13, the voltage comparator 14, the switch 15, the step-down switching DC / DC circuit 16, and the power limiter 17 are provided on the printed circuit board. I have.

  The protection circuit 11 protects the subsequent circuit portion from overcurrent and overvoltage. The rectifier circuit 12 rectifies the input voltage (AC voltage) input via the protection circuit 11. The filter circuit 13 removes noise components from the input voltage rectified by the rectifier circuit 12. The voltage comparator 14 compares the input voltage from which the noise component has been removed by the filter circuit 13 with a threshold value. The switch 15 switches the LED block units B <b> 1 and B <b> 2 to be fed among the LED modules 20 that are loads according to the comparison result of the voltage comparator 14.

  More specifically, as shown in FIG. 2, a switch 15 for switching the operation of the step-down switching DC / DC circuit 16 and a switch 15 for switching the operation of the power limiter 17 are provided. The comparison results of the voltage comparator 14 are input to these switches 15, and the switches 15 are turned on / off according to the comparison results.

(Operation example)
FIG. 3 is a flowchart showing an operation example of the LED driver module 10 according to the first embodiment. 4 is a graph showing waveforms of the LED driver module 10 according to the first embodiment. FIG. 4A is an input voltage waveform, FIG. 4B is an output voltage waveform, and FIG. c) shows an output current waveform. Hereinafter, an operation example of the LED driver module 10 will be described with reference to these drawings.

  First, when the power is turned on (FIG. 3, step S1), the input voltage is rectified by the rectifier circuit 12, and the noise component is removed by the filter circuit 13. Next, as shown in FIG. 4A, the input voltage from which the noise component has been removed is compared with a threshold (for example, 30 V) by the voltage comparator 14 (FIG. 3, step S2).

  Here, when the input voltage is equal to or higher than the threshold value, power is supplied to all the LED block units B1 and B2 by the step-down switching DC / DC circuit 16 (FIG. 3, step S3). Specifically, the case where the input voltage is equal to or higher than the threshold is the period A shown in FIG. The step-down switching DC / DC circuit 16 generates a desired DC voltage by stepping down the output of the filter circuit 13. At that time, as shown in FIG. 4C, constant current control is performed to maintain the output current flowing through the LED module 20 at a constant value (for example, 120 mA).

  On the other hand, when the input voltage is not equal to or higher than the threshold value, the power limiter 17 supplies power to only a part of the LED block B2 (FIG. 3, step S4). That is, power is not supplied to the LED block portion B1. Specifically, the case where the input voltage is not equal to or higher than the threshold is a period B shown in FIG. Even in this case, as shown in FIG. 4B, a voltage of 15 V or more is supplied to the LED block B2, and when the peak of the output current is 100%, an output area of 5% or less should not exist. ing. Thereby, it becomes possible to provide the LED bulb 1 with almost no flicker.

(LED bulb)
FIG. 5 is a schematic front perspective view showing a configuration example of the LED bulb 1 according to the first embodiment. As shown in this figure, the LED bulb 1 includes an LED driver module 10, an LED module 20 that is fed from the LED driver module 10, a case 30 in which the LED driver module 10 and the LED module 20 are mounted, and an LED module 20. And a translucent cover 40 covering the.

  For example, the LED bulb 1 has a mini-krypton shape corresponding to an E17 base, and has an outer diameter of 35 mm and a total length of 67 mm or less. The size of the printed circuit board 10a forming the LED driver module 10 is 28.0 mm × 11.5 mm or less. Since this printed circuit board 10a is not mounted with a large volume electrolytic capacitor, it can be easily accommodated in the mini-krypton type LED bulb 1. Of course, a heat spreader or a heat sink may be provided in order to prevent the LED bulb 1 from reaching an excessive temperature.

(LED driver module)
FIG. 6 is a schematic circuit block configuration diagram showing a configuration example of the LED driver module 10 according to the first embodiment. As shown in this figure, the LED driver module 10 includes input terminals LP1 to LP2, output terminals LP3 to LP5, npn bipolar transistors Q1 and Q2, resistors R1 to R7, capacitors C1 to C7, and a diode D1. And coils L1 and L2, a diode bridge DB1, a fuse F1, a varistor VR1, a Zener diode ZD1, and a MOSFET 14a.

  The input terminal LP1 is a via (plated hole) to which the live terminal L of the commercial AC power supply 2 is connected. The input terminal LP2 is a via to which the neutral terminal N of the commercial AC power supply 2 is connected.

  The output terminal LP3 is a via to which the first anode terminal A1 of the LED module 20 is connected. The output terminal LP4 is a via to which the second anode terminal A2 of the LED module 20 is connected. The output terminal LP5 is a via to which the cathode terminal C of the LED module 20 is connected.

  The first end of the fuse F1 is connected to the input terminal LP1. The second end of the fuse F1 is connected to the first end of the varistor VR1. The second end of the varistor VR1 is connected to the input terminal LP2. The fuse F1 and the varistor VR1 form a protection circuit 11.

  The first input terminal of the diode bridge DB1 is connected to the second terminal of the fuse F1. A second input terminal of the diode bridge DB1 is connected to the input terminal LP2. The diode bridge DB1 forms a rectifier circuit 12.

  The first end of the capacitor C1 is connected to the first output end of the diode bridge DB1. The second end of the capacitor C1 is connected to the output terminal LP5. A first end of the resistor R1 is connected to a second output end of the diode bridge DB1. A second end of the resistor R1 is connected to the output terminal LP5. The capacitor C1 and the resistor R1 form a filter circuit 13.

  The collector of the transistor Q1 is connected to the first output terminal of the diode bridge DB1 and the first terminal of the Zener diode ZD1. The emitter of the transistor Q1 is connected to the first end of the resistor R4 and the anode of the diode D1. The base of the transistor Q1 is connected to the collector of the transistor Q2, the second end of the resistor R2, and the first end of the capacitor C2. The base of the transistor Q2 is connected to the cathode of the diode D1 and the first terminal of the capacitor C3. The emitter of the transistor Q2 is connected to the second end of the resistor R4 and the second end of the capacitor C3. The second end of the capacitor C2 is connected to the first end of the coil L2. The second end of the coil L2 is connected to the first end of the coil L1, the second end of the resistor R4, and the cathode of the diode D2. The second end of the coil L1 is connected to the output terminal LP3. The transistor Q1, the resistor R2, the capacitor C3, and the Zener diode ZD1 form a main switch 15a. The Zener diode ZD1 may be about 30V. Transistor Q2, resistor R4, capacitor C3, and diode D1 form a constant current comparator 16a. Coils L1 and L2 form an oscillation circuit 16b.

  The anode of the diode D2 is connected to the output terminal LP5. The first end of the capacitor C6 is connected to the second end of the resistor R4. The second end of the capacitor C5 is connected to the output terminal LP5. A first end of the resistor R5 is connected to the gate of the MOSFET 14a. A second end of the resistor R5 is connected to the output terminal LP5. The drain of the MOSFET 14a is connected to the first output terminal of the diode bridge DB1. The source of the MOSFET 14a is connected to the first end of the capacitor C7 and the first end of the resistor R6. The diode D2, the capacitor C6, the resistor R5, and the MOSFET 14a form a voltage comparator 14. The MOSFET 14 a corresponds to the switch 15.

  A first end of a capacitor (ceramic capacitor) C7 is connected to the source of the MOSFET 14a. The second end of the capacitor C7 is connected to the output terminal LP5. Capacitor C7 forms output smoothing capacitor 18b.

  A first end of the resistor R6 is connected to the source of the MOSFET 14a. A second end of the resistor R6 is connected to the output terminal LP4. Resistor R6 forms a power limiter 17.

  A first end of the resistor R7 is connected to a second end of the resistor R6. A second end of the resistor R7 is connected to the output terminal LP5. The resistor R7 forms a bleeder 19 for a firefly switch. The firefly switch is a switch provided on a wall surface or the like as a means for switching on / off of the LED bulb 1, and is provided with a small light emitting portion that is turned on when the LED bulb 1 is turned off and turned off when the LED bulb 1 is turned on.

  A first end of the capacitor C4 is connected to the output terminal LP3. The second end of the capacitor C4 is connected to the first end of the capacitor C5. The second end of the capacitor C5 is connected to the output terminal LP5. Capacitors C4 and C5 form an output smoothing capacitor 18a. As a result, an LED drive voltage is generated.

  Here, the current capacity in the period A shown in FIG. 4 is determined by the resistor R4, and the current capacity in the period B is determined by the resistor R6. In the period A, the LED drive voltage is supplied to the LED module 20 using the output terminals LP3 to LP5. On the other hand, in the period B, the MOSFET 14a is turned on, and the LED drive voltage is supplied to the LED module 20 using the output terminals LP4-LP5. Thereby, even if an input voltage is below a threshold value (30V), the number of series can be reduced to half and the LED module 20 can be light-emitted. Even when the input voltage becomes 15 V or less, it is possible to continue supplying the LED module 20 with the electric charge stored in the ceramic capacitor C7.

(Printed circuit board)
FIG. 7 is a schematic plan view showing a configuration example of the printed circuit board 10a according to the first embodiment, in which FIG. 7A shows the front surface and FIG. 7B shows the back surface. As already described, the size of the printed circuit board 10a is 28.0 mm × 11.5 mm or less. As shown in this figure, input terminals LP1 to LP2, output terminals LP3 to LP5, and MOSFET 14a are mounted on the printed circuit board 10a. Of course, other components constituting the LED driver module 10 such as resistors and transistors are also mounted. Also, pads PD1 to PD14 for contacting the probe during the test are formed. The symbol O in the figure is the probe processing origin.

  For comparison, a schematic plan view showing a configuration example of a conventional printed circuit board 10b is shown in FIG. FIG. 8A shows the front surface, and FIG. 8B shows the back surface. As shown in this figure, the conventional printed circuit board 10b has two output terminals LP3 and LP4. It can be seen that the MOSFET 14a is not provided.

(LED module)
FIG. 9 is a schematic circuit block configuration diagram showing a configuration example of the LED module 20 according to the first embodiment. As shown in this figure, the LED module 20 includes a first anode terminal A1, a second anode terminal A2, a cathode terminal C, and LED elements D1 to D12 and D21 to D32.

  Here, 24 LED elements are connected in 12 × 2 in parallel. Specifically, the LED elements D1 to D12 are connected in series, and the LED elements D21 to D32 are also connected in series. LED elements D1-D12 and D21-D32 are connected in parallel. The anodes of the LED elements D1 and D21 are connected to the first anode terminal A1. The anodes of the LED elements D7 and D27 are connected to the second anode terminal A2. The cathodes of the LED elements D12 and D32 are connected to the cathode terminal C. LED element D1-D6 and D21-D26 form LED block part B1. LED element D7-D12 and D27-32 form LED block part B2.

  As described above, in the present embodiment, a plurality of LED elements are connected in parallel in n series × m pieces to provide redundancy. Of course, the LED module 20 is not limited to the configuration shown in FIG. For example, as shown in FIG. 10, two LED elements D1, D2,..., D23 and D24 connected in parallel may be connected in series, and Zener diodes D25 to D36 may be provided at each position. . Also in this case, the second anode terminal A2 is connected to a position (an anode of the LED elements D13 and D14) that bisects the series connection. The position to which the second anode terminal A2 is connected is not limited to this, and can be changed as appropriate. However, when the peak of the output current is 100%, it is preferable to change within a range where there is no output area of 5% or less.

(Alumina substrate)
FIG. 11 is a schematic plan view showing a configuration example of the alumina substrate 21a according to the first embodiment. Here, each LED element is described as “LED element D” without distinction. The alumina substrate 21a is a substrate constituting the LED module 20, and includes a first anode terminal A1, a second anode terminal A2, a cathode terminal C, a plurality of LED elements D, and a phosphor layer 22. I have. Details of the phosphor layer 22 will be described later.

  For comparison, a schematic plan view showing a configuration example of a conventional alumina substrate 21b is shown in FIG. As shown in this figure, the conventional alumina substrate 21b has one anode terminal A.

(Example of schematic cross-sectional structure of LED module)
FIG. 13 is a schematic cross-sectional structure example of the LED module 20 according to the first embodiment. The LED module 20 employs a COB structure.

  As shown in this figure, wiring patterns 23 and 24 are formed on an alumina substrate 21a. An LED element D is mounted on the wiring pattern 23, and an upper surface electrode (not shown) of the LED element D and the wiring pattern 24 are connected by a bonding wire 25. A white resin bank (dam material) 26 includes a phosphor layer 22 in which a first light-emitting phosphor 22a and a second light-emitting phosphor 22b are mixed and dispersed in a translucent resin.

  For example, the LED element D may be formed of a blue LED formed of a nitride semiconductor. In this case, both the first light emitting phosphor 22a and the second light emitting phosphor 22b may be formed of a yellow phosphor. Alternatively, in order to ensure color rendering, the first light emitting phosphor 22a may be formed of a red phosphor, and the second light emitting phosphor 22b may be formed of a green phosphor.

Here, as a yellow phosphor using a blue LED as an excitation light source, for example, Ce-doped YAG (Y ₃ Al ₅ O ₁₂ : Ce) phosphor, Eu-added α-sialon (CaSiAlON: Eu), silicate phosphor (( Sr, Ba, Ca, Mg) ₂ SiO ₄ : Eu) or the like can be used. That is, part of the blue light of the blue light emitting LED can be converted into yellow light emission by the yellow phosphor, and white light emission can be obtained by blue + yellow light emission.

Examples of the green phosphor using a blue LED as an excitation light source include Eu-added β-sialon (Si _6-z Al _z O _z N _8-z : Eu) phosphor, Ce-added CSSO (Ca ₃ Sc ₂ Si). _{A 3} O ₁₂ : Ce) phosphor or the like can be used.

In addition, as a red phosphor using a blue LED as an excitation light source, for example, an Eu-added CaAlSiN ₃ (CaAlSiN ₃ : Eu) phosphor can be used.

  The LED element D may be formed of an ultraviolet LED formed of a nitride semiconductor. In this case, both the first light emitting phosphor 22a and the second light emitting phosphor 22b may be formed of a yellow phosphor. Alternatively, in order to ensure color rendering, the first light emitting phosphor 22a may be formed of a blue phosphor, and the second light emitting phosphor 22b may be formed of a yellow phosphor.

  As the blue phosphor using the ultraviolet light LED as the excitation light source, any material that emits blue light upon receiving ultraviolet light may be used. For example, a halogenate phosphor, an aluminate phosphor, a silicate phosphor, etc. Can be mentioned. Examples of the activator include elements such as cerium, europium, manganese, gadolinium, samarium, terbium, tin, chromium, and antimony. Among these, europium is preferable. The addition amount of the activator is preferably in the range of 0.1 to 10 mol% with respect to the phosphor.

  The yellow phosphor using an ultraviolet LED as an excitation light source may be either a phosphor that absorbs blue light emission and emits yellow light, or a phosphor that absorbs ultraviolet light and emits yellow light. Here, in order to ensure color rendering properties, when the first light emitting phosphor 22a is formed of a blue phosphor and the second light emitting phosphor 22b is formed of a yellow phosphor, in order to further increase the light emission efficiency, ultraviolet rays are used. A phosphor that absorbs and emits yellow light is desirable. Examples of phosphors that absorb blue light emission and emit yellow light include organic phosphors such as allylsulfoamide / melamine formaldehyde co-condensed dyes and perylene phosphors, and inorganic phosphors include alumina. Examples thereof include acid salts, phosphates, and silicates. Among these, perylene phosphors and YAG phosphors are particularly preferable because they can be used for a long time. Examples of the activator include elements such as cerium, europium, manganese, gadolinium, samarium, terbium, tin, chromium, and antimony. Of these, cerium is preferred. The addition amount of the activator is preferably in the range of 0.1 to 10 mol% with respect to the phosphor. As a combination of the phosphor and the activator, a combination of YAG and cerium is preferable.

Examples of the phosphor that absorbs ultraviolet rays and emits yellow light include phosphors such as (La, Ce) (P, Si) O ₄ and (Zn, Mg) O. Examples of the activator include terbium and zinc.

  The contents of the first light-emitting phosphor 22a and the second light-emitting phosphor 22b in the phosphor layer 22 may be appropriately determined based on the LED element D, the type of the phosphor, and the like. In any case, the range of 1 to 25 wt% relative to the phosphor layer 22 is desirable.

  The white LED mounted on the LED module 20 according to the embodiment may be mounted using a general LED mounting package.

  Further, as a configuration of the LED, for example, a “blue LED + green LED + red LED” can be accommodated in one package to configure a white LED. As an example of such a multi-chip, a phosphor that emits yellow light by blue light excitation in a multi-chip of “infrared LED + blue LED” can be combined. Since the yellow phosphor is not affected by infrared light, it can be configured in one small package, can occupy a small space, and can be mounted in a small space.

  As described above, in the present embodiment, the input voltage is compared with the threshold value, and the LED block units B1 and B2 to be fed are switched according to the comparison result. Therefore, it is not necessary to mount an electrolytic capacitor having a large volume, and it is possible to provide an LED driver module 10 that is reduced in size and weight and an LED bulb 1 using the LED driver module 10.

  Further, when the output current peak is 100%, the LED block portions B1 and B2 to be fed are switched so that there is no output area of 5% or less. Thereby, it becomes possible to provide the LED bulb 1 with almost no flicker.

[Second Embodiment]
Hereinafter, only differences between the second embodiment and the first embodiment will be described.

(Threshold)
FIG. 14 is a diagram for explaining the threshold value according to the second embodiment. FIG. 14A is a graph showing the relationship between the input voltage from which the noise component has been removed and the threshold value, and FIG. b) is a schematic block diagram showing a relationship between a switch 15 mounted on the LED driver module 10 and a threshold value. Here, it is assumed that the LED module 20 includes a plurality of LED elements (VF: 3V, for example) connected in series of n pieces in series × m pieces. In this case, as shown in FIG. 14A, n threshold values S_1 to S_n may be set at intervals of 3V, for example. Accordingly, as illustrated in FIG. 14B, the switch 15 can be switched in n stages according to the n threshold values S_1 to S_n.

(overall structure)
FIG. 15 is a schematic block diagram illustrating a configuration example of the LED bulb 1 according to the second embodiment. Here, it is assumed that n LED block portions B1 to Bn are provided. In this case, n power limiters 17_1 to 17_n are provided in the subsequent stage of the switch 15, and the power limiters 17_1 to 17_n are switched by the switch 15 according to the n threshold values S_1 to S_n. Such a configuration has an advantage that the step-down switching DC / DC circuit 16 is not necessary, although it is necessary to provide a larger number of electrodes on the LED module 20 side as compared with the first embodiment.

  More specifically, as shown in FIG. 16, a switch 15 for switching the operation of the n power limiters 17_1 to 17_n is provided. The comparison results of the voltage comparator 14 are input to these switches 15, and the switches 15 are turned on / off according to the comparison results.

(Operation example)
FIG. 17 is a flowchart showing an operation example of the LED driver module 10 according to the second embodiment. Here, the case where the LED block units B1 to Bn to be fed are switched so that there is no output area of 5% or less when the peak of the output current is 100% will be described as an example.

  First, when the power is turned on (FIG. 17, step S11), the voltage comparator 14 compares the input voltage from which the noise component has been removed with the threshold value S_1 (FIG. 17, step S12). Here, the input voltage is compared in order from the highest value of the n threshold values S_1 to S_n, and when the input voltage is equal to or higher than the kth compared threshold value S_k, the power supply limiter 17 supplies power to the LED block units Bk to Bn. It is like that.

  Specifically, when the input voltage is equal to or higher than the highest threshold value S_1, power is supplied to all the LED block units B1 to Bn (FIG. 17, step S13). On the other hand, when the input voltage is not equal to or higher than the highest threshold value S_1, the input voltage is compared with the second highest threshold value S_2 (FIG. 17, step S14). When the input voltage is equal to or higher than the second highest threshold value S_2, power is supplied to the LED block units B2 to Bn (FIG. 17, step S15). Thereafter, the same processing is repeated until the input voltage becomes equal to or higher than the lowest threshold value S_n (FIG. 17, step S16).

  As described above, also in this embodiment, the input voltage is compared with the threshold values S_1 to S_n, and the LED block units B1 to Bn to be fed are switched according to the comparison result. The same effect as the embodiment can be obtained. Furthermore, although it is necessary to provide many electrodes on the LED module 20 side as compared with the first embodiment, there is an advantage that the step-down switching DC / DC circuit 16 becomes unnecessary.

[Third Embodiment]
Hereinafter, only the points of the third embodiment different from the first or second embodiment will be described with reference to FIGS.

(LED driver module)
The LED driver module 10 according to the present embodiment includes a main switch 15a connected to the filter circuit 13, and a constant current comparator 16a connected between the main switch 15a and the MOSFET 14a (switch 15). A MOSFET is used for 16a.

In the first embodiment, a bipolar transistor Q2 is provided as shown in FIG. The transistor Q2, the resistor R4, the capacitor C3, and the diode D1 form a constant current comparator 16a. If the reference voltage _{V REF} of the transistor Q2 is greater than the voltage _{V 2} across resistor R4, the transistor Q2 is turned on, if the reference voltage _{V REF} of the transistor Q2 of the voltage _{V 2} or less according to the resistor R4 a transistor Q2 is turned off and Become.

Here, the reference voltage _{V REF} of the transistor Q2 is determined by the base-emitter voltage _{V BF} of the forward voltage _{V F} and the transistor Q2 of the diode D1. Since the diode D1 and the base-emitter of the transistor Q2 is made of silicon, the reference voltage V _REF of the transistor Q2 has a negative temperature characteristic. Therefore, when the temperature becomes high, the reference voltage V _{REF of the} transistor Q2 decreases, and the output current to the LED module 20 decreases.

  Therefore, in the present embodiment, a MOSFET is used for the constant current comparator 16a. Hereinafter, the present embodiment will be described in more detail with reference to the drawings.

FIG. 18 is a schematic circuit block configuration diagram illustrating a configuration example of the LED driver module 10 according to the third embodiment. The difference from the first embodiment is that a MOSFET 31 is provided instead of the bipolar transistor Q2. The bipolar transistor Q2 is controlled by the input current, whereas the MOSFET 31 is controlled by the electric field by the input voltage. That is, MOSFET 31 has an operating principle different from that of bipolar transistor Q2, and does not cause a problem that the reference voltage _VREF decreases even when the temperature becomes high. Therefore, the expected output current can be obtained, and the LED module 20 can emit light with the expected brightness. If the MOSFET 31 is provided in place of the bipolar transistor Q2 in this way, it is not necessary to pass a bias current, so that power consumption can be reduced by about 1.5%. Furthermore, there is a merit that the diode D1 and the capacitor C3 are unnecessary. A gate resistor R8 for attenuating noise is provided at a place where the diode D1 is provided.

(Printed circuit board)
In the present embodiment, a high-profile component is mounted on the front surface of the printed circuit board 10c forming the LED driver module 10, and a low-profile component is mounted on the back surface.

  Alternatively, the fuse F1, the varistor VR1, the diode bridge DB1, and the oscillation circuit 16b may be mounted in this order from the input terminals LP1 and LP2 on the surface, and the notch 41 may be formed on the output terminals LP3 and LP4 on the surface.

  Moreover, the lead wire 50 connected to the LED module 20 may be wired through the notch 41 from the front surface to the back surface.

  FIG. 19 is a schematic plan view showing a configuration example of a printed circuit board 10c according to the third embodiment, in which FIG. 19A shows the front surface and FIG. 19B shows the back surface.

  As shown in FIG. 19A, components such as a fuse F1, a varistor VR1, a diode bridge DB1, and an oscillation circuit 16b are mounted on the surface in order from the input terminals LP1 and LP2. The surface parts are mainly high-profile parts. On the other hand, as shown in FIG. 19B, components such as the bipolar transistor Q1 and the MOSFET 31 are mounted on the back surface. The parts on the back are mainly low-profile parts. As described above, when a high-profile component is mounted on one surface and a low-profile component is mounted on the other surface, the printed circuit board 10c can be saved in space. Of course, the component mounting form is not limited to the form shown in FIG. For example, the MOSFET 31 may be mounted on the surface. In addition, it is preferable to employ all-surface mounting parts for both the front and back surfaces.

  As shown in FIGS. 19A and 19B, two rectangular cutouts 41 are formed outside the output terminals LP3 and LP4 of the printed circuit board 10c. Lead wires are drawn out from the output terminals LP3 and LP4, and are connected to the LED module 20. This notch 41 is for wiring the lead wire 50 from the front surface to the back surface. That is, when the printed circuit board 10c is mounted on the case 30 of the LED bulb 1, when the notch 41 is not formed, the lead wire 50 is connected to the end of the printed circuit board 10c as shown in FIG. It becomes bulky and disturbing. On the other hand, when the notch 41 is formed, the lead wire 50 can be wired from the front surface to the back surface through the notch 41 as shown in FIG. Since low-back type components are mounted on the back surface, the lead wire 50 can escape in the center direction of the printed circuit board 10c (left direction in FIG. 20). Therefore, the printed circuit board 10c can be easily mounted on the case 30 of the LED bulb 1.

  Here, the case where two rectangular cutouts 41 are formed outside the output terminals LP3 and LP4 of the printed circuit board 10c is illustrated, but the shape and number of the cutouts 41 are particularly limited. It is not a thing. For example, as shown in FIG. 21, one rectangular cutout 44 may be formed inside the output terminals LP3 and LP4. Even in this case, the lead wire 50 can be wired through the notch 44 from the front surface to the back surface.

  Further, as shown in FIGS. 19A and 19B, two notches 42 are formed at the edge near the center of the printed circuit board 10c. That is, as shown in FIG. 22A, the notches 42 are formed on the assumption that a certain amount of burrs are generated when a large number of printed circuit boards 10c are cut out from one sheet member 51.

  Further, as shown in FIGS. 19A and 19B, two notches 43 are formed outside the input terminals LP1 and LP2 of the printed circuit board 10c. If such a notch 43 is formed, as shown in FIG. 22B, when the printed circuit board 10 c is mounted on the case 30 of the LED bulb 1, the printed circuit board 10 c contacts the base of the case 30. It becomes difficult to do.

  As described above, in the present embodiment, the MOSFET 31 is provided in place of the bipolar transistor Q2, so that the expected output current can be obtained even at a high temperature, and the LED module has the expected brightness. 20 can emit light. If the MOSFET 31 is provided in place of the bipolar transistor Q2 in this way, it is not necessary to pass a bias current, so that power consumption can be reduced by about 1.5%. Furthermore, there is a merit that the diode D1 and the capacitor C3 are unnecessary.

  In the present embodiment, a high-profile component is mounted on the front surface of the printed circuit board 10c forming the LED driver module 10, and a low-profile component is mounted on the back surface. Thereby, space saving of the printed circuit board 10c can be achieved.

  In the present embodiment, the fuse F1, the varistor VR1, the diode bridge DB1, and the oscillation circuit 16b are mounted in this order from the front side of the input terminals LP1 and LP2, and a notch 41 is formed on the front side of the output terminals LP3 and LP4. ing. Thereby, since each component is efficiently arranged, it is possible to reduce the area of the printed circuit board 10c.

  In the present embodiment, the lead wire 50 connected to the LED module 20 is wired through the notch 41 from the front surface to the back surface. Thereby, the lead wire 50 can escape to the center direction of the back surface of the printed circuit board 10c. Therefore, the printed circuit board 10c can be easily mounted on the case 30 of the LED bulb 1.

[Fourth Embodiment]
Hereinafter, only differences between the fourth embodiment and the third embodiment will be described with reference to FIGS.

(LED driver module)
The LED driver module 10 according to the present embodiment includes a main switch 15a connected to the filter circuit 13, and a constant current comparator 16a connected between the main switch 15a and the MOSFET 14a (switch 15). MOSFET is used for the above.

FIG. 23 is a schematic circuit block configuration diagram showing a configuration example of the LED driver module 10 according to the fourth embodiment. The difference from the third embodiment is that a MOSFET 32 is provided instead of the bipolar transistor Q1. That is, since the base-emitter of the bipolar transistor Q1 is also made of silicon, the base-emitter voltage _VBF decreases at a high temperature. Then, since the base current _{I B} increases, the collector current _{I C} rises, the transistor Q1 generates heat. As a result, the base-emitter voltage _VBF further decreases, which may cause thermal runaway and destroy the transistor Q1.

Therefore, in this embodiment, as shown in FIG. 23, a MOSFET 32 is used for the main switch 15a. As a result, there is no problem that the base-emitter voltage _VBF decreases to the reference voltage _VREF even when the temperature becomes high. Therefore, it is possible to prevent the transistor Q1 from being destroyed due to thermal runaway.

  Further, as shown in FIG. 23, the MOSFET 32 is provided with two Zener diodes D3 and D4 in both directions for overvoltage protection. The Zener voltages (for example, 16V) of these Zener diodes D3 and D4 are not less than the gate voltage of the MOSFET 32 and not more than the breakdown voltage (for example, 30V) between the gate and the drain.

(Printed circuit board)
FIG. 24 is a schematic plan view showing a configuration example of a printed circuit board 10c according to the fourth embodiment, in which FIG. 24 (a) shows the front surface and FIG. 24 (b) shows the back surface. As shown in FIG. 24B, a MOSFET 32 is mounted on the back surface instead of the bipolar transistor Q1. Two Zener diodes D3 and D4 are mounted in both directions. Other points are the same as in the third embodiment (see FIG. 19).

  As described above, in this embodiment, the MOSFET 32 is provided instead of the bipolar transistor Q1. Therefore, it is possible to prevent the transistor Q1 from being destroyed due to thermal runaway even at a high temperature.

  As described above, according to the present invention, it is possible to provide the LED driver module 10 reduced in size and weight and the LED bulb 1 using the LED driver module 10.

[Other embodiments]
As described above, the present invention has been described according to the first to fourth embodiments. However, it should be understood that the descriptions and drawings constituting a part of this disclosure are exemplary and limit the present invention. should not do. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art.

  As described above, the present invention includes various embodiments not described herein. For example, a case has been described where control is performed so that no output area of 5% or less exists when the peak of the output current is 100%, but the value of “5%” is not particularly limited. That is, it can be appropriately changed according to the contents stipulated in the Electrical Safety Law and the like.

  The LED driver module and the LED bulb according to the present invention can be applied to a lighting device that requires space saving and reduction in size and weight. In particular, it is effective to apply to a lighting device that needs to prevent flicker.

DESCRIPTION OF SYMBOLS 1 ... LED bulb 10 ... LED driver module 11 ... Protection part (protection circuit)
12 ... Rectifier (rectifier circuit)
13: Filter section (filter circuit)
14 ... Voltage comparator (voltage comparator)
15 ... Switch part (switch)
15a ... main switch 16 ... step-down switching DC / DC circuit 16a ... constant current comparator 16b ... oscillation circuits 17, 17_1, ..., 17_n ... power limiter 20 ... LED modules B1, B2, ..., Bn ... LED Block portions D1 to D12, D21 to D32 ... LED elements 30 ... cases 31, 32 ... MOSFETs
40 ... Translucent cover 41 ... Notch 50 ... Lead wire F1 ... Fuse VR1 ... Varistor DB1 ... Diode bridge

Claims (26)

A protection unit that protects the subsequent circuit portion from the input voltage;
A rectifying unit that rectifies an input voltage input through the protection unit;
A filter unit for removing noise components from the input voltage rectified by the rectifying unit;
A voltage comparison unit that compares the input voltage from which noise components have been removed by the filter unit with a threshold;
An LED driver module comprising: a switch unit that switches an LED block unit that is a power supply target among LED modules that are loads in accordance with a comparison result of the voltage comparison unit.   2. The LED driver according to claim 1, wherein the switch unit switches the LED block unit to be fed so that there is no output area of 5% or less when the peak of the output current is 100%. module. The LED module includes a plurality of LED elements connected in series of n pieces in series x m pieces,
2. The LED driver module according to claim 1, wherein the switch unit switches a series number of the LED elements according to a comparison result of the voltage comparison unit.   When the input voltage is equal to or higher than a threshold value, power is supplied to all LED block parts by a step-down switching DC / DC circuit. When the input voltage is not higher than the threshold value, power is supplied to some LED block parts by a current limiter. The LED driver module according to claim 3.   The input voltage is compared in order from the highest value of n threshold values, and when the input voltage is equal to or higher than the kth threshold value, power is supplied to the LED block units Bk to Bn by a current limiter. Item 4. The LED driver module according to Item 3.   The LED driver module according to claim 1, wherein a size of a printed circuit board forming the LED driver module is 28.0 mm × 11.5 mm or less.   The LED driver module according to claim 1, wherein the LED module has a COB structure. A main switch connected to the filter unit;
A constant current comparator connected between the main switch and the switch unit;
The LED driver module according to claim 1, wherein a MOSFET is used for the constant current comparator. A main switch connected to the filter unit;
A constant current comparator connected between the main switch and the switch unit;
The LED driver module according to claim 1, wherein a MOSFET is used for the main switch.   2. The LED driver according to claim 1, wherein a high-profile type component is mounted on one surface of a printed circuit board forming the LED driver module, and a low-profile component is mounted on the other surface. module.   The fuse, varistor, diode bridge, and oscillation circuit are mounted in this order from the input terminal side of the one surface, and a notch is formed on the output terminal side of the one surface. LED driver module.   The LED driver module according to claim 11, wherein a lead wire connected to the LED module is wired from the one surface to the other surface through the notch. A protection unit that protects a circuit unit at a subsequent stage from the input voltage; a rectification unit that rectifies the input voltage input via the protection unit; and a filter unit that removes a noise component from the input voltage rectified by the rectification unit; The voltage comparison unit that compares the input voltage from which the noise component has been removed by the filter unit with a threshold value, and the LED block unit that is a power supply target among the LED modules that are loads according to the comparison result of the voltage comparison unit. An LED driver module comprising a switch unit for switching;
An LED module powered by the LED driver module;
A case in which the LED driver module and the LED module are mounted;
An LED bulb comprising: a translucent cover that covers the LED module.   14. The LED bulb according to claim 13, wherein the switch unit switches the LED block unit to be fed so that there is no output area of 5% or less when the peak of the output current is 100%. . The LED module includes a plurality of LED elements connected in series of n pieces in series x m pieces,
The LED light bulb according to claim 13, wherein the switch unit switches a series number of the LED elements in accordance with a comparison result of the voltage comparison unit.   When the input voltage is equal to or higher than a threshold value, power is supplied to all LED block parts by a step-down switching DC / DC circuit. When the input voltage is not higher than the threshold value, power is supplied to some LED block parts by a current limiter. The LED bulb according to claim 15, wherein   The input voltage is compared in order from the highest value of n threshold values, and when the input voltage is equal to or higher than the kth threshold value, power is supplied to the LED block units Bk to Bn by a current limiter. Item 16. The LED bulb according to item 15.   The LED bulb according to claim 13, wherein the LED bulb has a mini-krypton shape.   The LED bulb according to claim 13, wherein the LED bulb has an outer diameter of 35 mm and a total length of 67 mm or less.   The LED bulb according to claim 13, wherein a size of a printed circuit board forming the LED driver module is 28.0 mm x 11.5 mm or less.   The LED bulb according to claim 13, wherein the LED module has a COB structure. A main switch connected to the filter unit;
A constant current comparator connected between the main switch and the switch unit;
14. The LED bulb according to claim 13, wherein a MOSFET is used for the constant current comparator. A main switch connected to the filter unit;
A constant current comparator connected between the main switch and the switch unit;
The LED bulb according to claim 13, wherein a MOSFET is used for the main switch.   The LED light bulb according to claim 13, wherein a high-profile type component is mounted on one surface of a printed circuit board forming the LED driver module, and a low-profile component is mounted on the other surface. .   25. The fuse, varistor, diode bridge, and oscillation circuit are mounted in this order from the input terminal side of the one surface, and a notch is formed on the output terminal side of the one surface. LED bulb.   26. The LED bulb according to claim 25, wherein a lead wire connected to the LED module is wired from the one surface to the other surface through the notch.

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