JP2017054767A - Light-emitting diode lighting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-emitting diode lighting device in consideration of commonization of components such as a substrate.SOLUTION: A light-emitting diode lighting device 1, used for lighting an LED 30c, an LED module 30 having a load discrimination resistor 30d connected in parallel to the LED 30c; a micro computer 14 that detects the number of the load discrimination resistors 30d and determines a current value for lighting the LED 30c on the basis of the number of the detected load discrimination resistors 30d.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a light emitting diode lighting device for lighting a light emitting diode.

  Light emitting diodes (hereinafter referred to as LEDs) are widely used as illumination and the like. It is known that the LED is controlled to be lit with a constant current (see, for example, Patent Document 1). In addition, the LED may be used by connecting one or a plurality of circuits connected in series in parallel depending on specifications such as required luminance and power consumption.

Japanese Patent No. 5239138

  However, when individually designing a circuit or the like according to a required specification, there are problems that a circuit, a substrate, or the like is different for each specification or that a design man-hour is required. That is, since the sharing of parts and the like has not been taken into account, this has been a factor in increasing costs.

  The present invention aims to solve such problems.

  That is, an object of the present invention is to provide a light emitting diode lighting device capable of suppressing an increase in cost in consideration of commonality.

  In order to solve the above-mentioned problems, the invention described in claim 1 is a light-emitting diode lighting device that lights a light-emitting diode, and is provided with load determination means connected in parallel with the light-emitting diode. A diode module; detection means for detecting the number of load determination means; and current control means for determining a current value for turning on the light-emitting diode based on the number of load determination means detected by the detection means. And a light emitting diode lighting device.

  The invention described in claim 2 is characterized in that, in the invention described in claim 1, the load discriminating means is constituted by a resistance element.

  The invention described in claim 3 is the invention described in claim 2, wherein the detection means detects the number of the load determination means based on a voltage value corresponding to a resistance value of the resistance element. It is a feature.

  The invention described in claim 4 is the invention described in any one of claims 1 to 3, wherein the detecting means detects the load determining means when the light emitting diode is not lit. It is what.

  According to the first aspect of the present invention, the load determination means is provided in the light emitting diode module, and the detection means detects the number of load determination means. Therefore, the number of the light emitting diode modules is determined, and the current control unit It is possible to drive at a constant current by determining a current according to the number. Therefore, by standardizing a light emitting diode module on which a predetermined number of LEDs are mounted in advance, if a plurality of LED modules are connected, it is possible to adjust brightness, lighting area, etc. corresponding to various specifications. Therefore, it is possible to suppress the cost increase by sharing the parts.

  Moreover, it is possible to prevent an overcurrent from flowing through the LED by detecting the load determining means. For example, when three light emitting diode modules are connected, even when only two load determination means can be detected, it is possible to drive with a current corresponding to the number of detected load determination means. Therefore, it is possible to drive with a current value excluding the current corresponding to the failed light emitting diode module.

  According to the second aspect of the present invention, since the load determining means is composed of a resistance element, no expensive parts are required, and the cost increase due to the addition of the load determining means can be minimized. .

  According to the third aspect of the present invention, since the voltage value may be detected, the number of load determination means can be easily detected.

  According to the invention described in claim 4, it is possible to detect the number of load discriminating means without affecting the lighting of the LED such as before the LED is turned on.

It is a circuit diagram of the light emitting diode lighting device concerning one Embodiment of this invention. FIG. 2 is a circuit diagram of the LED module shown in FIG. 1. FIG. 2 is a circuit diagram in which two LED modules shown in FIG. 1 are connected. 3 is an operation flowchart of the light-emitting diode lighting device shown in FIG. 1. It is an example of a table that defines the correspondence between the number of parallel voltage input terminals and resistors and the output voltage value.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 to 5. FIG. 1 is a configuration diagram of a light-emitting diode lighting device according to an embodiment of the present invention.

  As shown in FIG. 1, the light-emitting diode lighting device 1 includes a power supply circuit unit 10 and an LED module (light-emitting diode module) 30.

  The power supply circuit unit 10 includes a first power supply unit 11, a second power supply unit 12, an FET driver 13, a microcomputer 14, FETs 15 and 16, a coil 17, a diode 18, and resistors 19, 20, 21 and 22. And a capacitor 23 and an operational amplifier 24.

  The 1st power supply part 11 is a power supply circuit which outputs the voltage of 10V, for example, and is provided in order to detect the load discrimination resistance provided in the LED module 30 mentioned later. The voltage output from the first power supply unit 11 may be equal to or less than Vf (forward voltage) of the LED module 30.

  The second power supply unit 12 is a power supply circuit that outputs a voltage of, for example, 80 V at the maximum, and supplies power for lighting the LEDs provided in the LED module 30. The voltage (current) that can be output from the second power supply unit 12 is desirably set to a value that can correspond to the maximum number of LED modules 30 to be connected.

  The FET driver 13 performs ON / OFF switching control of the FETs 15 and 16 under the control of the microcomputer 14.

  The microcomputer 14 is a microcomputer including a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like, and operates according to a control unit program stored in the ROM. The microcomputer 14 governs overall control of the power supply circuit unit 10. The microcomputer 14 performs analog / digital conversion on the voltage value input to the voltage input terminal Va, determines the number of LED modules 30 connected from the voltage value (digital value), and the power supply circuit unit 10 The current value supplied to the LED module 30 is determined.

  The FETs 15 and 16 are field effect transistors. The FET 15 has a gate connected to the output terminal of the high side gate driver of the FET driver 13, a drain connected to the second power supply unit 12, and a source connected to the source connection terminal of the high side FET of the FET driver 13 and the drain of the FET 16. And one end of the coil 17. The FET 16 has a gate connected to the FET driver 13, a drain connected to the output terminal of the low-side gate driver of the FET driver 13, the source of the FET 15, and one end of the coil 17, and the source is grounded. The gates of the FETs 15 and 16 are controlled by the FET driver 13 to perform a switching operation. A diode connected in parallel with the FETs 15 and 16 is a parasitic diode.

  One end of the coil 17 is connected to the sources of the FET driver 13 and FET 15 and the drain of the FET 16, and the other end is connected to the cathode of the diode 18, one end of the resistor 20, one end of the resistor 22, one end of the capacitor 23, and the + input terminal of the operational amplifier 24. It is connected to the.

  The diode 18 has an anode connected to the other end of the resistor 19, and a cathode connected to the other end of the coil 17, one end of the resistor 20, one end of the resistor 22, one end of the capacitor 23, and the + input terminal of the operational amplifier 24.

  The resistor 19 has one end connected to the first power supply unit 11 and the other end connected to the anode of the diode 18. The resistor 19 is set to a resistance value of 22 kΩ in this embodiment. The resistor 20 has one end connected to the other end of the coil 17, the cathode of the diode 18, one end of the resistor 22, one end of the capacitor 23, and the + input terminal of the operational amplifier 24, and the other end connected to one end of the resistor 21 and the voltage input of the microcomputer 14. It is connected to the terminal Va. The resistor 20 is set to a resistance value of 510 kΩ in this embodiment. One end of the resistor 21 is connected to the other end of the resistor 20 and the voltage input terminal Va of the microcomputer 14, and the other end is grounded. The resistor 21 is set to a resistance value of 33 kΩ in this embodiment. The resistor 22 has one end connected to the other end of the coil 17, the cathode of the diode 18, one end of the resistor 20, one end of the capacitor 23, and the + input terminal of the operational amplifier 24, and the other end connected to the −input terminal of the operational amplifier 24 and the LED module 30. It is connected to the. In this embodiment, the resistor 22 is set to a resistance value of 0.5 kΩ.

  The capacitor 23 has one end connected to the other end of the coil 17, the cathode of the diode 18, one end of the resistor 20, one end of the resistor 22, and the + input terminal of the operational amplifier 24, and the other end is grounded.

  The operational amplifier 24 has a + input terminal connected to the other end of the coil 17, a cathode of the diode 18, one end of the resistor 20, one end of the resistor 22, and one end of the capacitor 23, and a − input terminal connected to the other end of the resistor 22 and the LED module 30. And an output terminal is connected to the microcomputer 14.

  Here, in the power supply circuit unit 10, the first power supply unit 11, the resistor 19, and the diode 18 are circuits for detecting a load determination resistor provided in the LED module 30 described later, and other configurations are well known. This is a constant current power supply circuit.

  As shown in FIG. 2, the LED module 30 includes connection terminals 30a, 30b, 30e, and 30f, an LED 30c, and a load determination resistor 30d. Moreover, the LED module 30 is comprised with a different board | substrate from the power supply circuit part 10, and can be attached or detached by connection terminal 30a, 30b.

  The connection terminals 30 a and 30 b are terminals for electrical connection with the power supply circuit unit 10. The connection terminal 30 a is connected to the side of the power supply circuit unit 10 where the resistor 22 and the operational amplifier 24 are connected, and the connection terminal 30 b is connected to the ground side of the power supply circuit unit 10.

  The LED 30c has a plurality of LED elements connected in series. In the example of FIG. 2, the number of series is 8 and Vf (forward voltage for 8 LED elements = voltage between connection terminals) = 35 V, but not limited thereto, the number of series may be 1 or more, Vf may be changed as appropriate.

  The load determination resistor 30d is connected in parallel with the LED 30c. The load discrimination resistor 30d is an LED module discrimination element (resistance element). The resistance value of the load determination resistor 30d is set to 510 kΩ in the example of FIG. Note that the load determination resistor 30d does not contribute to the lighting of the LED 30c. Therefore, it is preferable that the resistance value of the load determination resistor 30d is a resistance with such a magnitude that current does not flow as much as possible when the LED 30c is turned on. However, it is necessary to determine the resistance value in relation to the number of LEDs 30c in series and the characteristics of the LED elements themselves. Absent.

  The connection terminals 30e and 30f are terminals for electrically connecting the other LED modules 30. The connection terminal 30e is connected to the connection terminal 30a of the other LED module 30, and the connection terminal 30f is connected to the connection terminal 30b of the other LED module 30. That is, the LED module 30 can be connected in a plurality of series by the connection terminals 30e and 30f. By doing in this way, several LED30c and load discrimination | determination resistance 30d will be connected in parallel. Of course, the connection terminals 30e and 30f are detachable from the connection terminals 30a and 30b of the other LED modules 30.

  The light emitting diode lighting device 1 configured as described above detects the parallel number of the load determination resistor 30d of the LED module 30 as a voltage value at the voltage input terminal Va of the microcomputer 14 based on the voltage supplied from the first power supply unit 11. To do. For example, when there is one LED module 30, one load determination resistor 30 d of 510 kΩ is connected and the parallel number is 1, so Va = 1.1V. Here, as shown in FIG. 3, when two LED modules 30 (31, 32) are connected, two load determination resistors 30d are connected, and the parallel number becomes two. The overall resistance value (synthetic resistance value) is 255 kΩ. In this case, Va = 1.6V.

  As described above, since the resistance value of the load determination resistor 30d is known in advance, the microcomputer 14 has a correspondence between the resistance value corresponding to the parallel number and the voltage value detected by the resistance value in advance. From the value, the parallel number of the load determination resistors 30d, that is, the number of the LED modules 30 connected to the power supply circuit unit 10 can be detected.

  Next, the operation of the light-emitting diode lighting device 1 shown in FIG. 1 will be described with reference to the flowchart of FIG.

  First, in step S <b> 1, the LED module 30 is connected to the power supply circuit unit 10. The number of connections may be 2 or more depending on the specifications of the lighting device or the like in which the light emitting diode lighting device 1 is used.

  Next, in step S2, the power is turned on. That is, the first power supply unit 11 and the second power supply unit 12 are activated.

  Next, in step S3, the microcomputer 14 is activated. The activated microcomputer 14 controls the FET driver 13 so that the FETs 15 and 16 are turned OFF after the initial setting of the microcomputer 14 is completed. Therefore, no current is supplied to the LED module 30 from the second power supply unit 12.

  Next, in step S4, the resistance value of the load determination resistor 30d is detected. That is, the combined resistance value of the load determination resistors 30d of all the LED modules 30 connected to the power supply circuit unit 10 is detected. As described above, this is detected by the microcomputer 14 based on the value of the voltage input terminal Va of the microcomputer 14. For example, it can be easily detected by presetting a table as shown in FIG. That is, the microcomputer 14 functions as a detection unit that detects the number of load determination units. Further, the microcomputer 14 detects the number of load determination means based on the voltage value corresponding to the resistance value of the resistance element.

  Next, in step S5, an output current is set. This sets the current value that the microcomputer 14 supplies to the LED module 30 from the power supply circuit unit 10. This current value varies depending on the number of LED modules 30 for constant current control of the LED 30c, and is set based on the table of FIG. In the case of the example of FIG. 5, it is set so that a current of 0.35 A flows per LED module 30. That is, the microcomputer 14 functions as a current control unit that determines a current value for turning on the light emitting diode based on the number of load determination units detected by the detection unit. Note that the table used in step S4 and the table used in step S5 may be determined separately.

  Next, in step S6, the current set in step S5 is output. In this step, the microcomputer 14 causes the FET driver 13 to perform a normal operation (an operation for supplying a current for turning on the LED 30c). In this way, the power supply circuit unit 10 can drive and drive the LED module 30 with constant current control. That is, in steps S4 and S5 executed before step S6, the load determining means is detected when the light emitting diode is not lit.

  In the above-described example, one or two LED modules 30 are connected. However, it is needless to say that three or more LED modules 30 can be connected. You can increase the number.

  According to the present embodiment, since the load determination resistor 30d is provided in the LED module 30, when the microcomputer 14 detects the combined resistance value of the load determination resistor 30d, the number of the LED modules 30 is determined. 14 can determine the current according to the number and perform constant current driving. Therefore, by standardizing the LED module 30 in which a predetermined number of LEDs are connected in series in advance, if a plurality of LED modules 30 are connected, the brightness, lighting region, and the like can be adjusted according to various specifications. . Moreover, since it is only necessary to change the number of connections of the LED module 30, no board design or the like is required for each specification, and it is possible to easily cope with a specification change or the like. Therefore, it is possible to suppress the cost increase by sharing the parts. Further, the non-lighting area can also be made constant within the range of the LED module 30.

  Further, by detecting the load determination resistor 30d, it is possible to prevent an overcurrent from flowing through the LED 30c. For example, when three LED modules 30 are connected, even when only two load determination resistors 30d can be detected, it is possible to drive with a current corresponding to the number of detected load determination resistors 30d. Therefore, it becomes possible to drive at a current value excluding the current corresponding to the failed LED module 30.

  Further, since the load discrimination resistor 30d is used as the load discrimination means, expensive parts are not required, and the cost increase due to the addition of the load discrimination means can be minimized.

  Further, since the number of load determination resistors 30d is detected based on the voltage value corresponding to the combined resistance value of the load determination resistor 30d, the voltage value may be detected, and the number of load determination resistors 30d (the LED module 30) can be easily detected. The number of connections) can be detected.

  Further, since the power supply circuit unit 10 detects the resistance value of the load determination resistor 30d when the LED 30c is not lit, the number of load determination resistors 30d (the number of connected LED modules 30) does not affect the lighting of the LED 30c. Can be detected.

  In the above-described embodiment, the LED modules 30 have all been described as having the same specifications. However, the present invention is not limited to this, and as long as Vf (voltage between connection terminals) is the same, the number of series and the specifications of the LED elements are different. Also good.

  Further, the present invention is not limited to the above embodiment. That is, those skilled in the art can implement various modifications in accordance with conventionally known knowledge without departing from the scope of the present invention. Of course, such modifications are also included in the scope of the present invention as long as the configuration of the light emitting diode lighting device of the present invention is provided.

DESCRIPTION OF SYMBOLS 1 Light emitting diode lighting device 10 Power supply circuit part 14 Microcomputer (detection means, current control means)
30 LED module 30c LED
30d Load discrimination resistance (load discrimination means)

Claims (4)

A light emitting diode lighting device for lighting a light emitting diode,
A light emitting diode module provided with a load discriminating means connected in parallel with the light emitting diode;
Detecting means for detecting the number of the load determining means;
Current control means for determining a current value for turning on the light emitting diode based on the number of the load determination means detected by the detection means;
A light-emitting diode lighting device comprising:   The light emitting diode lighting device according to claim 1, wherein the load determination unit is configured by a resistance element.   The light emitting diode lighting device according to claim 2, wherein the detection unit detects the number of the load determination units based on a voltage value corresponding to a resistance value of the resistance element.   The light emitting diode lighting device according to any one of claims 1 to 3, wherein the detecting means detects the load determining means when the light emitting diode is not lit.

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