LED driving module

Abstract

The present invention relates to an LED driving module. An LED driving module using an UV LED according to an embodiment of the present invention may include a fault detection unit. The fault detection unit may detect a fault in the UV LED. The fault detection unit may include a connection status detection unit that detects a connection status of the UV LED. Furthermore, the connection status detection unit may output a fault signal from a fault signal output terminal when a fault due to a short circuit or open circuit occurs in the UV LED.

Description

[Technical Field]

[0001] The present invention relates to an LED driving module. [Background technology]

[0002] Light-emitting diodes (LEDs) have various advantages, such as small size, high brightness relative to power consumption, long service life, and low manufacturing costs, and are therefore used as lighting means and display means to replace existing light bulbs.

[0003] Depending on their light-emitting properties, LEDs can be classified into infrared LEDs that emit infrared rays, visible light LEDs that emit visible light, and ultraviolet LEDs that emit ultraviolet rays. Ultraviolet (UV) LEDs have been applied to various products after being confirmed to be effective in eliminating bacteria that contain DNA (deoxyribonucleic acid) and RNA (ribonucleic acid). In recent years, compact products that use a single light-emitting diode have been developed for ease of storage and portability.

[0004] Generally, a product can be completed by installing a separately manufactured light emitting diode and a driving module for driving the light emitting diode inside.

[0005] As described above, when a failure occurs in a product using an LED, it is difficult to immediately determine whether the failure is due to a defect in the LED itself or in another component. Summary of the Invention [Problem to be solved by the invention]

[0006] SUMMARY OF THE INVENTION An object of the present invention is to provide an LED driving module that detects a faulty state of an ultraviolet LED and outputs a fault signal to notify the same.

[0007] Another object of the present invention is to provide an LED driving module that outputs a failure signal that can determine the type of failure that has occurred in the UV LED.

[0008] Another object of the present invention is to provide an LED driving module that detects a defect in an ultraviolet LED and is suitable for a small product that uses a single ultraviolet LED. [Means for solving the problem]

[0009] According to an embodiment of the present invention, there is provided an LED driving module using a single UV LED including a fault detector. The fault detector can detect a fault in the UV LED. The fault detector can include a connection status detector that detects a connection status of the UV LED. The connection status detector can output a fault signal from a fault signal output terminal when a fault occurs in the UV LED due to a short circuit or an open circuit.

[0010] The connection state detector may include a connection detection switch that is turned on and off in response to a voltage of a node connected to the UV LED.

[0011] The node connected to the UV LED may be connected to an anode terminal of the UV LED. The connection detection switch may include first, second, and third terminals for receiving and outputting a signal. A voltage corresponding to a node voltage that turns the connection detection switch on and off may be applied to the first terminal. The second terminal may be connected to the fault signal output terminal. The third terminal may be connected to ground.

[0012] For example, the fault signal output terminal may include a first fault signal output terminal and a second fault signal output terminal, the first fault signal output terminal may output a first fault signal when the ultraviolet LED is in a short-circuit state, and the second fault signal output terminal may output a second fault signal when the ultraviolet LED is in an open state.

[0013] The first fault signal output terminal may be connected to a node connecting the second terminal of the connection detection switch and one terminal of a resistor. The second fault signal output terminal may be connected to a node connecting two resistors in series between the anode terminal of the UV LED and ground. The other terminal of the resistor connected to the second terminal of the connection detection switch may be connected to ground.

[0014] The defect detector may further include a heat detector for detecting a heat generation state of the UV LED.

[0015] The heat detection unit may include a thermal resistor whose resistance changes depending on the ambient temperature, and a heat detection switch connected to the thermal resistor. The thermal resistor may be connected to an anode terminal of the UV LED. The heat detection switch may be turned on or off in response to a voltage that changes depending on the resistance of the thermal resistor.

[0016] The heat detection switch may include a first terminal, a second terminal, and a third terminal for receiving or outputting a signal. The first terminal may receive a voltage that varies depending on the resistance value of the thermal resistor. The second terminal may be connected to the fault signal output terminal. The third terminal may be connected to ground.

[0017] For example, the fault signal output terminal may include a first fault signal output terminal, a second fault signal output terminal, and a third fault signal output terminal. The first fault signal output terminal may output a first fault signal when the ultraviolet LED is in a short-circuit state. The second fault signal output terminal may output a second fault signal when the ultraviolet LED is in an open state. The third fault signal output terminal may output a third fault signal when the ultraviolet LED is in an overheat state.

[0018] The first fault signal output terminal may be connected to a node connecting the second terminal of the connection detecting switch and one terminal of a resistor. The second fault signal output terminal may be connected to a node connecting two resistors in series between the anode terminal of the UV LED and ground. The third fault signal output terminal may be connected to a node connecting the second terminal of the heat detecting switch and one terminal of a resistor. The other terminal of the resistor connected to the second terminal of the connection detecting switch and the other terminal of the resistor connected to the second terminal of the heat detecting switch may be connected to ground, respectively.

[0019] The connection state detector may include an open detector for detecting an open state of the ultraviolet LED, and a short detector for detecting a short state of the ultraviolet LED.

[0020] Each of the open circuit detector and the short circuit detector may include an amplifier that compares an input voltage with a reference voltage, and at least one switch that is turned on and off by an output signal of the amplifier.

[0021] The open detection unit may include an open detection switch. The open detection switch may include a first terminal, a second terminal, and a third terminal that receive or output a signal. The first terminal may receive a voltage that turns the switch on or off according to a signal output from an amplifier of the open detection unit. The second terminal may be connected to the fault signal output terminal. When the open detection switch is in an on state, a current input via the first terminal may pass through the third terminal.

[0022] The short circuit detection unit may include a short circuit detection switch. The short circuit detection switch may include a first terminal, a second terminal, and a third terminal that receive a signal or output a signal. The first terminal may receive a voltage that turns the switch on or off according to a signal output from an amplifier of the short circuit detection unit. The second terminal may be connected to the fault signal output terminal. When the short circuit detection switch is in an on state, the current input via the first terminal may pass through the third terminal.

[0023] The fault signal output terminal can output a normal signal when the ultraviolet LED is in a normal state.

[0024] The fault signal may have a lower voltage than the normal signal.

[0025] The LED driving module may further include a Zener diode having one end connected to the fault signal output terminal and the other end connected to ground, where the normal signal may be a Zener voltage.

[0026] The LED driving module may further include a current sensing unit and a control signal generating unit. The current sensing unit may sense a current supplied to the UV LED. The control signal generating unit may generate and output a signal to control a switch according to the current value sensed by the current sensing unit. The control signal generating unit may output a short signal to turn on the switch and an open signal to turn off the switch to the switch. The connection status sensing unit may sense the short signal and the open signal output by the control signal generating unit to the switch. In this case, the fault sensing unit may generate and output a fault signal if the short signal or the open signal sensed by the connection status sensing unit is sensed for a predetermined period of time or longer.

[0027] The fault detector may further include a heat detector configured to detect the temperature of the UV LED or the temperature around the UV LED, and the fault detector may generate and output a fault signal when the temperature detected by the heat detector is equal to or higher than a predetermined temperature.

[0028] The LED driving module may further include a constant current unit that supplies a constant current to the UV LED. [Effects of the Invention]

[0029] According to an embodiment of the present invention, it is possible to determine whether a defect occurring in a product is caused by the UV LED by using an LED driving module that detects a defective state of the UV LED.

[0030] Furthermore, according to the embodiment of the present invention, the LED driving module outputs a signal according to the type of defect occurring in the UV LED, so that the defective state of the UV LED can be accurately determined.

[0031] Furthermore, according to an embodiment of the present invention, the LED driving module can be adapted to a small product by implementing a circuit for detecting a fault in an LED with a simple circuit, thereby minimizing an increase in size. [Brief explanation of the drawings]

[0032] [Figure 1] 1 is a block diagram showing a simplified configuration of an LED driving module according to a first embodiment of the present invention. [Figure 2] 1 is a block diagram of an LED driving module according to a first embodiment of the present invention. [Figure 3] 3 is a circuit diagram of a defect detection unit of the LED driving module according to the first embodiment of the present invention; FIG. [Figure 4] FIG. 10 is a block diagram showing functions included in an LED driving module according to a second embodiment of the present invention. [Figure 5] FIG. 6 is a circuit diagram of an LED driving module according to a second embodiment of the present invention. [Figure 6] 10 is a simplified block diagram of an LED driving module according to a third embodiment of the present invention. [Figure 7] FIG. 10 is a circuit diagram showing an LED driving module according to a fourth embodiment of the present invention. [Figure 8] 10 is a block diagram showing an LED driving module according to a fifth embodiment of the present invention. [Figure 9] 1 is a block diagram showing a simplified system of an ultraviolet LED device according to one embodiment of the present invention. [Figure 10] FIG. 10 is a block diagram showing a simplified system of an ultraviolet LED device according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0033] Hereinafter, each embodiment of the present invention will be described in detail with reference to the accompanying drawings. The following embodiments are provided as examples to fully convey the concept of the present invention to those skilled in the art. Therefore, the present invention is not limited to the following embodiments, and may be embodied in other forms. In the drawings, the width, length, thickness, etc. of components may be exaggerated for convenience. The same reference numerals refer to the same components, and similar reference numerals refer to corresponding similar components throughout the specification.

[0034] Hereinafter, the LED driving module of the present invention will be described in detail with reference to the accompanying drawings.

[0035] The LED driving module according to each embodiment of the present invention is a module applied to a small product using an ultraviolet LED. The LED driving module according to each embodiment of the present invention can detect a defect in the ultraviolet LED and generate and output a corresponding defect signal. More specifically, the LED driving module can output a normal signal indicating a normal state and a defect signal indicating a defective state depending on the state of the ultraviolet LED. Hereinafter, various embodiments of the present invention will be described with reference to the drawings, focusing on a defect detector that detects a defect in the ultraviolet LED.

[0036] 1 to 3 are diagrams illustrating an LED driving module according to a first embodiment of the present invention.

[0037] Fig. 1 is a block diagram showing a simplified configuration of an LED driving module according to a first embodiment of the present invention. Fig. 2 is a block diagram of the LED driving module according to the first embodiment of the present invention. Fig. 3 is a circuit diagram of a fault detection unit of the LED driving module according to the first embodiment of the present invention.

[0038] 1 to 3, the LED driving module 10 according to the first embodiment of the present invention may include an UV LED 11, a constant current unit 12, and a fault detection unit 13. Also, referring to FIG. 2, in the LED driving module 10 according to the first embodiment, the constant current unit 12 may be located at the rear end of the UV LED 11. That is, in the LED driving module 10 according to the first embodiment, the constant current unit 12 is connected to the cathode terminal of the UV LED 11 and can control the current flowing through the UV LED 11.

[0039] The LED driving module 10 according to this embodiment is a module that is applied to small products and can include one ultraviolet LED 11.

[0040] The constant current unit 12 can make a constant current flow through the ultraviolet LED 11 when the ultraviolet LED 11 is turned on. The constant current unit 12 controls the current flowing through the ultraviolet LED 11 to be constant, and can make the intensity of the ultraviolet light emitted from the ultraviolet LED 11 constant.

[0041] The constant current unit 12 may be implemented as a circuit having various structures using resistors, transistors, diodes, Zener diodes, etc. The constant current unit 12 of the present embodiment may include any of the known constant current circuits.

[0042] The defect detector 13 can detect a defect occurring in the ultraviolet LED 11 .

[0043] According to this embodiment, the fault detector 13 may include a connection status detector 110 and a heat detector 150 .

[0044] The connection state detector 110 can detect an abnormality in the connection state of the ultraviolet LEDs 11. That is, the connection state detector 110 can detect a fault in the connection state of the ultraviolet LEDs 11, such as an open circuit or a short circuit.

[0045] In addition, the heat detection unit 150 can detect the heat generation state of the UV LED 11 by detecting the ambient temperature. When the UV LED 11 emits UV light, heat can be generated by various causes, such as contact between a semiconductor and a metal, lattice vibrations (phonons), thermal conversion of light reabsorbed by total reflection at the surface, and leakage current. When the UV LED 11 emits heat, the ambient temperature of the UV LED 11 increases. As the ambient temperature of the UV LED 11 increases, the ambient temperatures of the other elements constituting the LED driving module 10 also increase. In other words, the heat detection unit 150 can detect a defect in the UV LED 11 by detecting a change in the ambient temperature.

[0046] In this way, the fault detector 13 detects the connection state and heat generation state between the anode and cathode terminals of the UV LED 11, and can output a fault signal to notify the abnormal state when it detects an abnormal state. Also, when the fault detector 13 does not detect a fault in the UV LED 11, it can output a normal signal to notify the normal state of the UV LED 11.

[0047] 2, the LED driving module 10 may include an input terminal 15 for receiving a signal from the outside and a fault signal output terminal 17 for outputting a signal to the outside. According to this embodiment, a driving voltage is provided to the UV LED 11 via the input terminal 15. In addition, a fault signal indicating a fault state of the UV LED 11 may be output via the fault signal output terminal 17. In addition, a normal signal indicating a normal state of the UV LED 11 may be output via the fault signal output terminal 17.

[0048] The constant current unit 12 may be located at the rear end of the UV LED 11. That is, the constant current unit 12 may be connected to the cathode terminal of the UV LED 11. The fault detection unit 13 may also be located at the rear end of the UV LED 11 and connected to the cathode terminal of the UV LED 11.

[0049] FIG. 3 is a circuit diagram of the LED driving module 10. Referring to FIG. 3, the circuit constituting the fault detection unit 13 of the LED driving module 10 may include a switch having a plurality of terminals for inputting or outputting signals. In this embodiment, the switch may be an NPN-type bipolar transistor. If the switch is a bipolar transistor, the switch may include three terminals for inputting or outputting signals. For example, the switch may include a first terminal that is a base terminal, a second terminal that is a collector terminal, and a third terminal that is an emitter terminal. In addition, the signal input to the switch may be a voltage or a current.

[0050] The heat detector 150 of this embodiment may include a thermal resistor 151, a first switch SW1, and a first resistor R1.

[0051] The thermal resistor 151 is an element whose resistance value changes with temperature. For example, the thermal resistor 151 may be a negative temperature coefficient thermistor (NTC thermistor) having a negative temperature coefficient of resistance, that is, a thermistor whose resistance value decreases as the temperature increases. That is, according to this embodiment, when the ambient temperature of the thermal resistor 151 is equal to or higher than a certain temperature, the resistance value of the thermal resistor 151 decreases.

[0052] A first end of the thermal resistor 151 may be coupled to the anode end of the UV LED 11, and a second end of the thermal resistor 151 may be coupled to a first end of the first resistor R1.

[0053] A first terminal of the first switch SW1 may be connected to a first node (Node 1) where a second terminal of the thermal resistor 151 and a first terminal of the first resistor R1 are connected. A second terminal of the first switch SW1 may be connected to a second terminal of the second switch SW2. The second terminal of the first switch SW1 may be connected to a fault signal output terminal 17, which is an output terminal of the fault detector 13.

[0054] In addition, the second terminal of the first resistor R1 and the third terminal of the first switch SW1 may be connected to ground.

[0055] According to an embodiment of the present invention, the connection status detector 110 may include a second switch SW2, a second resistor R2, a third resistor R3, and a fifth resistor R5.

[0056] The second resistor R2 may have a first terminal connected to the cathode terminal of the UV LED 11 and a second terminal connected to a first terminal of the third resistor R3, i.e., the second resistor R2 and the third resistor R3 may be connected in series.

[0057] A first terminal of the fourth resistor R4 may be connected to the cathode terminal of the UV LED 11. That is, the first terminal of the fourth resistor R4 may be connected to a second node (Node 2) where the cathode terminal of the UV LED 11 and the first terminal of the second resistor R2 are connected. Also, a second terminal of the fourth resistor R4 may be connected to a first terminal of the fifth resistor R5. That is, the fourth resistor R4 and the fifth resistor R5 may be connected in series. Also, the fourth resistor R4 and the fifth resistor R5 may be connected in parallel with the second resistor R2 and the third resistor R3.

[0058] A first terminal of the second switch SW2 may be connected to a third node (Node 3) where the second terminal of the fourth resistor R4 and the first terminal of the fifth resistor R5 are connected together. A second terminal of the second switch SW2 may be connected to a fourth node (Node 4) where the second resistor R2 and the third resistor R3 are connected together, and to a fifth node (Node 5) where the second terminal of the first switch SW1 is connected together. That is, the second terminal of the second switch SW2 may be connected to a fault signal output terminal 17 of the fault detection unit 13.

[0059] The second end of the fifth resistor R5, the third end of the second switch SW2, and the second end of the third resistor R3 may be coupled to ground.

[0060] In the present embodiment, the fault detector 13 may be configured such that the heat detector 150 and the connection status detector 110 are connected to the fault signal output terminal 17. That is, the fault detector 13 may be configured such that the heat detector 150 and the connection status detector 110 share the same fault signal output terminal 17. Therefore, the fault detector 13 may output a fault signal when detecting either a fault due to heat generation or a fault due to the connection status of the UV LEDs 11.

[0061] According to this embodiment, the fault detector 13 can set the voltage of the fault signal output terminal 17 to 0V when a fault occurs in the UV LED 11 due to heat generation or connection state. That is, the fault detector 13 of the LED driving module 10 of this embodiment may be designed so that the 0V voltage output from the fault signal output terminal 17 becomes a fault signal indicating that the UV LED 11 is faulty.

[0062] When the UV LED 11 generates heat, the temperature around the UV LED 11 rises. Because the LED driving module 10 of this embodiment is small, the heat generated by the UV LED 11 also rises the temperature around the thermal resistor 151. Therefore, the heat detection unit 150 of this embodiment can detect the degree of heat generation from the UV LED 11 based on the ambient temperature detected by the thermal resistor 151.

[0063] For example, the resistance value of the thermal resistor 151 of the heat detection unit 150 may decrease as the ambient temperature increases. Also, a voltage divided by the thermal resistor 151 and the first resistor R1 may be applied to the first terminal of the first switch SW1. As the resistance value of the thermal resistor 151 decreases with an increase in the ambient temperature, the voltage applied to the first terminal of the first switch SW1 also increases.

[0064] At this time, when a voltage higher than a preset operating voltage of the first switch SW1 is applied to the first terminal of the first switch SW1, the first switch SW1 may be turned on. Here, the operating voltage is a reference voltage for turning on or off the first switch SW1. As such, in this embodiment, the operating voltage may be a reference for distinguishing between normal heat generation and abnormal overheating of the UV LEDs 11. For example, the operating voltage of each switch may be set to a threshold voltage. The first switch SW1 of the heat detection unit 150 is a heat detection switch that is operated according to the heat temperature of the UV LEDs 11.

[0065] When the first switch SW1 is turned on, the current flowing through the fourth node (Node 4) passes through the first switch SW1, and the voltage of the fault signal output terminal 17 may become 0V.

[0066] In this manner, when the ambient temperature exceeds a predetermined temperature due to the ultraviolet LED 11, the heat detector 150 of this embodiment turns on the first switch SW1 to generate a fault signal indicating a fault in the ultraviolet LED 11. Here, the predetermined temperature is a temperature that serves as a reference for an overheating state that occurs when the ultraviolet LED 11 is abnormal.

[0067] When the UV LED 11 is in a normal heat generation state, a voltage sufficient to maintain the first switch SW1 in an off state is applied to the first end of the first switch SW1 by the thermal resistor 151. That is, when the UV LED 11 is in a normal heat generation state, the first switch SW1 is maintained in an off state.

[0068] According to the present embodiment, the connection state detector 110 can detect a fault in the connection state of the ultraviolet LEDs 11. That is, the connection state detector 110 can detect a short circuit or an open circuit occurring in the ultraviolet LEDs 11.

[0069] The connection state detector 110 can set the voltage applied to the fault signal output terminal 17 to 0V when the UV LED 11 is in a short-circuit state.

[0070] The second switch SW2 has a first terminal connected to a third node (Node 3), and can be turned on or off depending on the voltage applied to the third node (Node 3).

[0071] For example, the second switch SW2 may be turned off when the voltage applied to the first terminal is lower than a preset operating voltage. The second switch SW2 may be turned on when the voltage applied to the first terminal is equal to or higher than the preset operating voltage. The preset operating voltage may be a reference for defining the short-circuit state of the UV LED 11. The operating voltage may be a threshold voltage of the second switch SW2. The second switch SW2 is a connection-sensing switch that operates according to the connection state of the UV LED 11.

[0072] When the UV LED 11 is in a normal state, a voltage drop occurs at the second node (Node 2) in the driving voltage equal to the operating voltage of the UV LED 11. When the UV LED 11 is in a normal state, a voltage lower than the preset operating voltage may be applied to the first terminal of the second switch SW2. At this time, the second switch SW2 may be maintained in an off state.

[0073] When the second switch SW2 maintains an off state, current flows through a fourth node (Node 4) connecting the second resistor R2 and the third resistor R3. At this time, a voltage divided by the second resistor R2 and the third resistor R3 may be output to the fault signal output terminal 17. For example, when the UV LED 11 is in a normal state, the voltage applied to the fault signal output terminal 17 may be expressed as follows in Equation 1:

[0074] [Formula 1] V fault =(V IN -V LED )·(R3 / (R2+R3))

[0075] where V fault is the voltage output from the fault signal output terminal 17, which is the fault signal. IN is the drive voltage provided through input 15, and V LED is the operating voltage of the UV LED, R2 is the second resistor, and R3 is the third resistor.

[0076] When the UV LED 11 is short-circuited, the voltage of the second node (Node 2) may be equal to the driving voltage. That is, when the UV LED 11 is short-circuited, a voltage higher than that when the UV LED 11 is in a normal state is applied to the second node (Node 2). At this time, the second switch SW2 may be turned on as a voltage equal to or higher than the preset operating voltage is applied to the first terminal.

[0077] When the second switch SW2 is turned on, current flows through the second resistor R2 and the second switch SW2 to ground, and the voltage at the fault signal output terminal 17 may become 0V.

[0078] Also, when the UV LED 11 is in an open state, the voltage applied to the second node (Node 2) is 0V, so the voltage of the fault signal output terminal 17 can become 0V.

[0079] The connection state detector 110 can output a fault signal of 0V to the fault signal output terminal 17 when the ultraviolet LED 11 is in a short-circuit state or an open state.

[0080] In this way, in the LED driving module 10 of this embodiment, when the heat generation and connection state of the ultraviolet LED 11 are both normal, the fault signal output terminal 17 outputs (V IN -V LED )·(R1 / (R1+R2)). In addition, the LED driving module 10 can output a fault signal whose voltage corresponds to 0V to the fault signal output terminal 17 when the UV LED 11 is short-circuited, open-circuited, or overheated.

[0081] The fault detection unit 13 of the LED driving module 10 of this embodiment outputs 0V from the fault signal output terminal 17 when a fault occurs in the UV LED 11, but is not limited to this. For example, the fault detection unit 13 may include a circuit that outputs any voltage other than 0V as the fault signal. That is, the fault signal of the fault detection unit 13 may be any predetermined voltage that is output when a fault occurs in the UV LED 11. In this case, the fault detection unit 13 may output a normal signal that can be distinguished from the fault signal when the UV LED 11 is in a normal state. In other words, the fault detection unit 13 of the LED driving module 10 of this embodiment may be configured with a circuit that can output a signal that can distinguish between a normal state and a fault state of the UV LED 11.

[0082] As described above, the LED driving module 10 of the present embodiment includes the failure detector 13 that outputs a signal that can distinguish between a normal state and a defective state of the ultraviolet LED 11. Therefore, when a defect occurs in a product to which the LED driving module 10 is applied, it can be determined whether the defect is due to the ultraviolet LED 11 or to another component. As a result, when a signal indicating a defect in the ultraviolet LED 11 is output, the defect in the product can be easily resolved by replacing the ultraviolet LED 11 without having to check whether other components are faulty.

[0083] In this embodiment, the thermal resistor 151 is described as an NTC thermistor. However, the heat detection unit 150 of this embodiment is not limited to this. For example, the thermal resistor 151 of the heat detection unit 150 may be a positive temperature coefficient thermistor (PTC thermistor) having a positive temperature coefficient of resistance, that is, a resistance value that increases as the temperature increases. In this case, the first switch SW1 of the heat detection unit 150 may be set to turn on at a preset operating voltage or lower.

[0084] Furthermore, the LED driving module 10 according to this embodiment has been described with reference to an example in which each switch included in the fault detection unit 13 is an NPN bipolar transistor. However, the type of switch applied to this embodiment is not limited to an NPN bipolar transistor. For example, each switch in the fault detection unit 13 may be configured as a diode or a MOSFET. Furthermore, the switch may be a transistor that turns on at a voltage lower than the operating voltage or threshold voltage. In this way, the switch can be any element that turns on or off according to an input signal.

[0085] As described above, the defect detector 13 according to the present embodiment can be implemented in various ways as long as it can detect whether the UV LED 11 is in a normal state or a defective state and output a signal that can distinguish between the normal state and the defective state.

[0086] The LED driving module 10 of this embodiment may be applied to a small product that uses one UV LED 11. As the demand for small products increases, the LED driving module 10 of this embodiment also maintains the size used for small products. In addition, the LED driving module 10 of this embodiment includes a fault detection unit 13 that detects an abnormality in the UV LED 11 and generates a signal in response to the abnormality.

[0087] The LED driving module 10 of this embodiment uses a simple circuit to detect a defect in the UV LED 11. Therefore, the LED driving module 10 of this embodiment can detect a defect in the UV LED 11 and output a signal to notify the defect while maintaining the size of a conventional LED driving module.

[0088] 4 and 5 are diagrams illustrating an LED driving module according to a second embodiment of the present invention.

[0089] Fig. 4 is a block diagram showing functions included in the LED driving module according to the second embodiment, and Fig. 5 is a circuit diagram of the LED driving module according to the second embodiment.

[0090] 4 and 5, the LED driving module 20 according to the second embodiment includes a constant current unit 12 and a fault detection unit 23.

[0091] The fault detector 23 of the present embodiment may include a heat detector 250 and a connection status detector 210. The connection status detector 210 of the present embodiment may include an open detector 220 and a short detector 230.

[0092] The fault detector 23 of the present embodiment can output signals via the heat detector 250, the open detector 220, and the short detector 230. That is, the fault detector 23 can detect a fault in the ultraviolet LED 11 and output a signal that can identify the type of the detected fault.

[0093] Referring to FIG. 5, the defect detector 23 of this embodiment can detect the overheating state, short circuit state, and open state of the ultraviolet LED 11 and output a corresponding signal.

[0094] The heat detector 250 of this embodiment may include a thermal resistor 151, a first switch SW1, a first resistor R1, a sixth resistor R6, and a seventh resistor R7.

[0095] A first end of the thermal resistor 151 may be connected to the anode end of the UV LED 11, and a second end of the thermal resistor 151 may be connected to a first end of the first resistor R1. The thermal resistor 151 and the first resistor R1 may be connected in series.

[0096] A first terminal of the sixth resistor R6 may be coupled to the cathode terminal of the ultraviolet LED 11, and a second terminal of the sixth resistor R6 may be coupled to the second terminal of the first switch SW1.

[0097] A first terminal of the first switch SW1 may be connected to a first node (Node 1) where the thermal resistor 151 and the first resistor R1 are connected, and a second terminal of the first switch SW1 may be connected to a second terminal of the sixth resistor R6.

[0098] The seventh resistor R7 may have a first terminal connected to the second terminal of the first switch SW1 and may be connected in parallel with the first switch SW1.

[0099] The second terminal of the first resistor R1, the third terminal of the first switch SW1, and the second terminal of the seventh resistor R7 of the heat detector 250 may be connected to ground.

[0100] The heat detection unit 250 may output a third fault signal and a normal signal from a node where the first switch SW1 and the seventh resistor R7 are connected. That is, a third fault signal output terminal 29 for outputting a signal related to the heat generation state of the ultraviolet LEDs 11 may be formed at a fifth node (Node 5) where the second terminal of the first switch SW1 and the third resistor R3 are connected.

[0101] The connection status detector 210 of this embodiment may include a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, an eighth resistor R8, a ninth resistor R9, and a second switch SW2.

[0102] A first terminal of the second resistor R2 may be connected to the cathode terminal of the UV LED 11. Also, a first terminal of the fourth resistor R4 and a first terminal of the eighth resistor R8 may be connected to a second node (Node 2) where the cathode terminal of the UV LED 11 and the second resistor R2 are connected.

[0103] The second terminal of the second resistor R2 may be connected to the first terminal of the third resistor R3. The second terminal of the fourth resistor R4 may be connected to the first terminal of the fifth resistor R5. The second terminal of the eighth resistor R8 may be connected to the second terminal of the second switch SW2. In this case, the second terminal of the third resistor R3, the second terminal of the fifth resistor R5, and the third terminal of the second switch SW2 may be connected to ground. The first terminal of the second switch SW2 may be connected to a third node (Node 3) where the fourth resistor R4 and the fifth resistor R5 are connected.

[0104] The connection status detector 210 of the present embodiment may output a first fault signal indicating an abnormal connection status of the UV LEDs 11 from a sixth node (Node 6) where the second terminal of the second switch SW2 and the ninth resistor R9 are connected. That is, a first fault signal output terminal 27 may be formed at the node where the second terminal of the second switch SW2 and the ninth resistor R9 are connected.

[0105] In addition, the connection status detector 210 of this embodiment may output a second fault signal indicating an abnormal connection status of the UV LEDs 11 from a fourth node (Node 4) where the second resistor R2 and the third resistor R3 are connected. That is, a second fault signal output terminal 28 may be formed at the node where the second resistor R2 and the third resistor R3 are connected.

[0106] 4, the short circuit detector 230 and the open circuit detector 220 are shown as separate components, which is a division of the function of the connection state detector 210. That is, the connection state detector 210 can output a signal corresponding to the open state or short circuit state of the UV LED 11 by operating one switch, as shown in FIG.

[0107] When the UV LED 11 is in a normal heating state, the ambient temperature of the thermal resistor 151 may also be within the normal temperature range. When the ambient temperature of the thermal resistor 151 is normal, a voltage that maintains the first switch SW1 in an off state is applied to the first terminal of the first switch SW1. When the first switch SW1 is in an off state, current flows through the sixth resistor R6 and the seventh resistor R7. Therefore, when the UV LED 11 is in a normal heating state, the third fault signal output terminal 29 may output a normal signal, which is a given voltage applied to the fifth node (Node 5). In this embodiment, the given voltage, which is the normal signal, output from the third fault signal output terminal 29 may be determined by the voltage of the second node (Node 2), the sixth resistor R6, and the seventh resistor R7.

[0108] When the ambient temperature of the thermal resistor 151 increases and the voltage applied to the first terminal of the first switch SW1 exceeds a preset operating voltage, the first switch SW1 may be turned on. When the first switch SW1 is turned on, current flows through the sixth resistor R6 and the first switch SW1, and the voltage of the fifth node (Node 5) may become 0V. In other words, when the UV LED 11 deviates from the normal range and enters an overheated state, the heat detection unit 250 may output a third fault signal of 0V from the third fault signal output terminal 29.

[0109] The heat detection unit 250 of this embodiment can detect the heat generation state of the ultraviolet LED 11 regardless of the connection state of the ultraviolet LED 11. That is, when the ultraviolet LED 11 is in an abnormal overheating state, the third fault signal is output from the third fault signal output terminal 29.

[0110] When the UV LED 11 operates in a normal connection state, a voltage that is the driving voltage dropped by the operating voltage of the UV LED 11 is applied to the second node (Node 2). At this time, a small voltage that is sufficient to maintain the second switch SW2 in an off state may be applied to the first terminal of the second switch SW2. That is, when the UV LED 11 is in a normal connection state, the second switch SW2 may be maintained in an off state.

[0111] When the second switch SW2 is in an off state, current flows to a sixth node (Node 6) where the eighth resistor R8 and the ninth resistor R9 are connected, and the signal output from the first fault signal output terminal 27 may be any voltage greater than 0V.

[0112] When the second switch SW2 is in an off state, the current flows through a fourth node (Node 4) where the second resistor R2 and the third resistor R3 are connected, and the signal output from the second fault signal output terminal 28 may be any voltage greater than 0V.

[0113] In this manner, when the connection state of the ultraviolet LED 11 is normal, the first fault signal output terminal 27 and the second fault signal output terminal 28 of the connection state detection unit 210 of this embodiment can output a normal signal, which is an arbitrary voltage greater than 0V.

[0114] When the UV LED 11 is in a short-circuit state, a voltage higher than that when the UV LED 11 is in a normal state is applied to the second node (Node 2). For example, when the UV LED 11 is in a short-circuit state, the voltage of the second node (Node 2) may be equal to the driving voltage. As the voltage of the second node (Node 2) increases, the voltage applied to the first terminal of the second switch SW2 also increases. When a voltage higher than the operating voltage of the second switch SW2 is applied to the first terminal of the second switch SW2, the second switch SW2 may be turned on.

[0115] When the second switch SW2 is turned on, the current that passed through the eighth resistor R8 passes through the second switch SW2, and the voltage of the first fault signal at the sixth node (Node 6) may become 0 V. Therefore, the first fault signal output terminal 27 may output the first fault signal of 0 V.

[0116] A current may flow through a fourth node (Node 4) connected to the second resistor R2 and the third resistor R3. At this time, the voltage of the fourth node (Node 4) may be any voltage greater than 0V depending on the voltage of the second node (Node 2), the second resistor R2, and the third resistor R3. Therefore, the second fault signal output terminal 28 may output a normal signal that is any voltage greater than 0V. In this embodiment, the any voltage may be set by resistors and switches that configure the circuit.

[0117] In this way, the fault detection unit 23 of this embodiment can output a first fault signal from the first fault signal output terminal 27 and a normal signal from the second fault signal output terminal 28 when the ultraviolet LED 11 is in a short-circuit state.

[0118] When the UV LED 11 is in an open state, a voltage much smaller than that when the UV LED 11 is in a normal state may be applied to the second node (Node 2). For example, when the UV LED 11 is in an open state, the voltage of the second node (Node 2) may be 0V.

[0119] Since the voltage of the second node (Node 2) is 0 V, the voltages of the fourth node (Node 4) and the sixth node (Node 6) may also be 0 V. Therefore, the first fault signal and the second fault signal, which are 0 V, may be output from the first fault signal output terminal 27 and the second fault signal output terminal 28, respectively.

[0120] In this way, the fault detection unit 23 of this embodiment can output a first fault signal from the first fault signal output terminal 27 and a second fault signal from the second fault signal output terminal 28 when the ultraviolet LED 11 is in an open state.

[0121] The following Table 1 shows the signals output from the defect detector 23 according to the state of the UV LED 11.

[0122] [Table 1]

[0123] In the LED driving module 20 according to the embodiment of the present invention, the fault detector 23 can output a normal signal or a fault signal from the first fault signal output terminal 27, the second fault signal output terminal 28, and the third fault signal output terminal 29 according to the fault state of the UV LED 11. Therefore, depending on the combination of the signals output from the first fault signal output terminal 27, the second fault signal output terminal 28, and the third fault signal output terminal 29, it is possible to determine not only whether the UV LED 11 is faulty, but also the type of fault occurring in the UV LED 11.

[0124] FIG. 6 is a simplified block diagram of an LED driving module according to a third embodiment of the present invention.

[0125] The LED driving module 10 according to the third embodiment of the present invention may include an ultraviolet LED 11, a constant current unit 12, and a fault detection unit 33.

[0126] 6, in the LED driving module 10 according to the third embodiment, the constant current unit 12 may be located at the front end of the UV LED 11. That is, the constant current unit 12 is connected to a node between an input terminal to which a voltage is input and an anode terminal of the UV LED 11, and can control the current flowing through the UV LED 11.

[0127] The constant current unit 12 of this embodiment is located at the front end of the ultraviolet LED 11 and can be any circuit that can control the current of the ultraviolet LED 11.

[0128] In addition, the fault detection unit 33 of this embodiment may be configured as the circuit of the fault detection unit 13 of the LED driving module 10 according to the first embodiment of FIG. 3, or the circuit of the fault detection unit 23 of the LED driving module 20 according to the second embodiment of FIG. 5.

[0129] FIG. 7 is a circuit diagram showing an LED driving module according to a fourth embodiment of the present invention.

[0130] Referring to FIG. 7, in the LED driving module 40 of the fourth embodiment, the constant current unit 42 can be located at the front end of the ultraviolet LED 11.

[0131] The LED driving module 40 of the fourth embodiment may include an ultraviolet LED 11, a constant current unit 42, a switch unit 46, and a fault detection unit 43. In this embodiment, the fault detection unit 43 may be a connection state detection unit. The fault detection unit 43 may include an open detection unit 420 and a short circuit detection unit 430.

[0132] The constant current unit 42 of this embodiment can control the switch unit 46 so that a constant current flows through the ultraviolet LEDs 11. The switch unit 46 of this embodiment can include a fourth switch SW4 and a fourth resistor R4. The fourth switch SW4 may be a p-type MOSFET.

[0133] In the LED driving module 40 of this embodiment, when the ultraviolet LED 11 is in a normal state, the open detection unit 420 and the short circuit detection unit 430 do not operate. Also, in the LED driving module 40 of this embodiment, when the ultraviolet LED 11 is in an open state, the open detection unit 420 operates, and when the ultraviolet LED 11 is in a short circuit state, the short circuit detection unit 430 operates.

[0134] In this embodiment, the constant current unit 42, the open circuit detection unit 420, and the short circuit detection unit 430 may each include an amplifier, a switch, and a resistor.

[0135] Each amplifier may be a negative feedback amplifier. A preset reference voltage and an input voltage may be input to each amplifier. Each amplifier may compare the input voltage with the input reference voltage and control a switch connected to the amplifier based on the comparison result. The amplifier controls the switch to output a voltage corresponding to the state of the UV LED 11 at the output terminal.

[0136] Each switch may be an NPN bipolar transistor, and the bipolar transistor switch may include a first terminal that is a base terminal, a second terminal that is a collector terminal, and a third terminal that is an emitter terminal.

[0137] Referring to FIG. 7, the constant current unit 42 includes a first amplifier OP1, a first-1 switch SW 11 , and switch 1-2 SW 12 The open circuit detector 420 includes a second amplifier OP2, a second-first switch SW 21 , and 2-2 switch SW 22 The short circuit detector 430 may also include a third amplifier OP3, a third-1 switch SW 31 , 3rd-2nd switch SW 32 Each switch of the open detector 420 is an open detector that operates depending on the open state of the ultraviolet LED 11. Also, each switch of the short detector 430 is a short detector that operates depending on the short state of the ultraviolet LED 11.

[0138] The first amplifier OP1, the second amplifier OP2, and the third amplifier OP3 can compare the input voltage with their respective preset reference voltages and output signals to turn on or off the respective switches connected thereto depending on the results.

[0139] The fifth resistor R5 and the sixth resistor R6 are connected in series with the cathode terminal of the UV LED 11. The first amplifier OP1 of the constant current unit 42 is connected to a first node (Node 1) where the fifth resistor R5 and the sixth resistor R6 are connected, and can receive a first node voltage. The first node voltage is a voltage applied to the first node. The first amplifier OP1 is connected to the first node voltage and a preset reference voltage V ref1 Compare with the first switch SW 11 Here, the first-1 switch SW 11 The signal that controls the 1-1 switch SW 11 The voltage may be input to the first terminal, which is the base terminal of the first-1 switch SW 11 When the first resistor R1 is turned on and the current flowing through the first resistor R1 increases, the first-second switch SW 12 The voltage input to the first terminal of the first-second switch SW 12 When the voltage input to the first terminal of the 12 may also be turned on.

[0140] In this way, the first amplifier OP1 of the constant current unit 42 is connected to the first node voltage and the reference voltage V ref1 The result of the comparison is 11 and 1-2 switch SW 12 Furthermore, by controlling the operation of the fourth switch SW4 of the switch unit 46 through the operation of the constant current unit 42, the current flowing through the ultraviolet LEDs 11 can be controlled to be constant.

[0141] The second amplifier OP2 of the open circuit detector 420 detects the voltage of the second node 2, which is connected between the cathode terminal of the UV LED 11 and the fifth resistor R5, and the reference voltage V ref2 and the second-first switch SW 21 Element and 2-2 switch SW 22 The operation of the element can be controlled. Here, the second node voltage is the voltage applied to the second node.

[0142] The third amplifier OP3 of the short circuit detector 430 is connected to the third node voltage of the third node (Node 3) where the eighth resistor R8 and the ninth resistor R9 are connected, and the reference voltage V ref3 and based on the result, the third-first switch SW 31 Element and 3-2 switch SW 32 The operation of the element can be controlled. Here, the third node voltage is the voltage applied to the third node.

[0143] When the ultraviolet LED 11 is in a normal state, the input voltages input to the second amplifier OP2 of the open circuit detector 420 and the third amplifier OP3 of the short circuit detector 430 may be higher than their respective reference voltages.

[0144] At this time, the second amplifier OP2 operates when the input voltage is equal to the reference voltage V ref2 Since it is higher, the second-first switch SW 21 The second switch SW 21 The second-1 switch SW2 receives the control signal from the second amplifier OP2 and outputs it as a control signal. 21 maintains its off state, thereby causing the second-2 switch SW 22 Therefore, when the ultraviolet LED 11 is in a normal state, the open detector 420 may be in an inactive state.

[0145] The third amplifier OP3 also operates when the input voltage is equal to the reference voltage V ref3 Since it is higher, the 3rd-1st switch SW 31 The voltage lower than the operating voltage of the 3-1 switch SW 31 The third-1 switch SW3 receives the control signal from the third amplifier OP3 and outputs it as a control signal. 31 remains in the off state, thereby causing the 3-3 switch SW 33 Therefore, when the UV LED 11 is in a normal state, the short circuit detector 430 may be in an inactive state.

[0146] In this way, when the UV LED 11 is in a normal state, a normal signal, which is a voltage indicating that the UV LED 11 is in a normal state, may be output from the fault signal output terminal 17. Here, the magnitude of the normal signal may be preset. For example, the voltage corresponding to the normal signal may be set using the constant voltage characteristic of the Zener diode 49. That is, when the UV LED 11 is in a normal state, the Zener voltage of the Zener diode 49 may be output. In this case, the Zener voltage of the Zener diode 49 may have a difference that can be distinguished from the voltage output from the fault signal output terminal 17 when the UV LED 11 is in an open state or a short state.

[0147] When the UV LED 11 is in a short circuit state, the first node voltage is equal to the reference voltage V of the second amplifier OP2. ref2 At this time, the signal output from the second amplifier OP2 turns on the second-1 switch SW 21 The second-2 switch SW 22 That is, when the ultraviolet LED 11 is in a short-circuit state, the open detector 420 may be in an inactive state.

[0148] At this time, the third node voltage is the reference voltage V of the third amplifier OP3 through the eighth resistor R8 and the ninth resistor R9. ref3 Furthermore, when the UV LED 11 is in a short-circuit state, the third node voltage can be maintained at a preset voltage value by the feedback system of the third amplifier OP3. At this time, the preset voltage value is the reference voltage V ref3 may be the same as

[0149] The third amplifier OP3 is connected to the third-first switch SW 31 The third amplifier OP3 outputs a signal to turn on the third switch SW 31 is turned on, which turns on the third-second switch SW 32 The 3rd-2nd switch SW 32is turned on, and the current flowing through the fourth node (Node 4) where the seventh resistor R7 and the Zener diode 49 are connected flows through the third-second switch SW 32 It will flow in this way.

[0150] Therefore, when the ultraviolet LED 11 is short-circuited, the fault signal output terminal 17 outputs a fault signal V as shown in the following [Equation 2]. fault A voltage corresponding to the voltage can be output.

[0151] [Formula 2] V fault =V CE32 +V ref3

[0152] where V CE32 is the 3rd-2nd switch SW 32 V CE is.

[0153] Furthermore, when the UV LED 11 is in a short-circuit state, the first and third node voltages, which are input voltages of the first and third amplifiers OP1 and OP3, can be maintained at a preset voltage value by the feedback system of the first and second amplifiers OP1 and OP2. For example, the preset voltage value may be the same as the reference voltage of each amplifier.

[0154] When the UV LED 11 is in a short-circuit state, the third node voltage is equal to the reference voltage V of the third amplifier OP3. ref3 is set equal to V CE32 Therefore, when the ultraviolet LED 11 is short-circuited, a voltage slightly higher than the third node voltage may be output from the fault signal output terminal 17 as a fault signal.

[0155] When the UV LED 11 is in an open state, the third node voltage is equal to the reference voltage V of the third amplifier OP3. ref3 At this time, the signal output from the third amplifier OP3 turns on the third-1 switch SW 31 is turned off, which turns off the third-second switch SW 32Therefore, the short circuit detector 430 may be in an inactive state.

[0156] When the UV LED 11 is in an open state, the third node voltage V node3 can be expressed as the following [Equation 3].

[0157] [Formula 3] V node3 =V IN (R9 / (R8+R9)

[0158] Also, when the ultraviolet LED 11 is in an open state, the first node voltage is equal to the reference voltage V of the second amplifier OP2. ref2 The second node voltage V node2 can be expressed as the following [Equation 4].

[0159] [Formula 4] V node2 =(V ref1 / R6)·(R5+R6)

[0160] For example, when the ultraviolet LED 11 is in an open state, the first node voltage may be 0V or a low voltage close to 0V.

[0161] The second amplifier OP2 receiving the first node voltage is connected to the second-first switch SW 21 Therefore, the second-first switch SW 21 and 2-2 switch SW 22 The second-2 switch SW 22 turns on, and the current flows through the second switch SW 22 The route may be changed to pass through

[0162] At this time, when the ultraviolet LED 11 is in an open state, the fault signal output terminal 17 outputs a fault signal V as shown in the following [Equation 5]. fault A voltage corresponding to the voltage can be output.

[0163] [Formula 5]

[0164] V fault =V node2 +V CE22

[0165] where V CE22 is the 2nd switch SW 22 V CE is.

[0166] When the UV LED 11 is open, V node2 is a very small voltage of 0V or close to 0V, and VCE22 is also a very small voltage. Therefore, when the ultraviolet LED 11 is in an open state, a very small voltage close to 0V may be output from the fault signal output terminal 17 as a fault signal.

[0167] According to this embodiment, when a fault such as a short circuit or an open circuit occurs in the ultraviolet LED 11, the fault signal output from the fault signal output terminal 17 may have a voltage that is lower than when the ultraviolet LED 11 is in a normal state. For example, when the ultraviolet LED 11 is in a faulty state, the fault signal output terminal 17 may output a voltage that is lower than the Zener voltage of the Zener diode 49.

[0168] In this way, in the LED driving module 40 of this embodiment, when the UV LED 11 is in a normal state, a preset voltage such as a Zener voltage is output from the fault signal output terminal 17, and when the UV LED is in an abnormal state, a voltage lower than the Zener voltage is output from the fault signal output terminal 17. Therefore, the state of the UV LED 11 can be determined based on the magnitude of the output voltage of the LED driving circuit of this embodiment.

[0169] The LED driving module 40 of this embodiment applies amplifiers to the open circuit detector 420 and the short circuit detector 430 and detects the short circuit and open circuit states of the UV LEDs 11 using a reference voltage within the amplifier. The LED driving module 40 of this embodiment uses amplifiers that have little deviation due to changes in the ambient environment, such as temperature, thereby minimizing deviations in the output voltage caused by changes in the ambient environment. Therefore, the LED driving module 40 of this embodiment minimizes deviations in the voltage used to determine whether the UV LEDs 11 are faulty, preventing errors that result in erroneous fault determination.

[0170] In this embodiment, the fourth switch SW4 of the switch unit 46 is described as a P-type MOSFET, but the type of the fourth switch SW4 is not limited to this. The fourth switch SW4 of the switch unit 46 may be any element that can be turned on or off according to an input value. In addition, the switches of the constant current unit 42, the open detection unit 420, and the short detection unit 430 may also be any element that can be turned on or off according to an input signal.

[0171] Furthermore, the LED driving module 40 of this embodiment may further include the heat detector described in the LED driving module of the previous embodiment.

[0172] FIG. 8 is a block diagram showing an LED driving module according to a fifth embodiment of the present invention.

[0173] Referring to FIG. 8, an LED driving module 50 according to a fifth embodiment of the present invention may include a current sensing unit 55, a control signal generating unit 56, and a fault sensing unit 53.

[0174] The current sensor 55 can sense the current supplied to the ultraviolet LED 11 .

[0175] The control signal generator 56 may generate a control signal for controlling the switch SW according to the current value sensed by the current sensor 55. The control signal generator 56 may generate a short signal for turning on the switch SW and an open signal for turning off the switch SW.

[0176] The switch SW may be turned on or off by a control signal received from the control signal generator 56. When the switch SW receives an open signal and is turned off, current may flow through the node to which the ultraviolet LED 11, the inductor L, and the diode 57 are connected. When the switch SW receives a short signal and is turned on, current may flow through the node to which the ultraviolet LED 11, the inductor L, and the switch SW are connected.

[0177] The fault detector 53 may include a heat detector 550 , an open signal detector 520 , a short signal detector 530 , and a fault signal generator 560 .

[0178] The heat detection unit 550 of this embodiment can detect the degree of heat generation from the UV LED 11. The heat detection unit can detect the temperature of the UV LED 11 or the ambient temperature and transmit a signal corresponding to the detected temperature to the fault signal generation unit 560. The fault signal generation unit 560 can generate and output a fault signal indicating a fault in the UV LED 11 based on the signal received from the heat detection unit 550. For example, the fault signal generation unit 560 can generate and output a fault signal when the temperature detected by the heat detection unit 550 exceeds a predetermined temperature.

[0179] The open signal detector 520 and the short signal detector 530 can detect the control signal of the control signal generator 56 applied to the switch SW.

[0180] The open signal detector 520 can detect the open signal applied by the control signal generator 56 to the switch SW.

[0181] For example, when the UV LED 11 is short-circuited, a current continuously flows through the node connected to the current sensing unit 55. That is, a current having a given magnitude may be continuously sensed by the current sensing unit 55. In this case, the control signal generating unit 56 may generate an open signal and transmit the open signal to the switch SW while the current sensing unit 55 senses a current having a given magnitude.

[0182] The open signal detector 520 detects the open signal of the control signal generator 56 and transmits a corresponding signal to the fault signal generator 560. In this case, if the open signal detector 520 detects the open signal for a predetermined period of time or longer, the fault signal generator 560 can determine that the ultraviolet LED 11 is in a short-circuit state. Therefore, if the control signal generator 56 generates the open signal for a predetermined period of time or longer, the fault signal generator 560 can generate and output a fault signal indicating a fault in the ultraviolet LED 11.

[0183] The short circuit signal detector 530 can detect the short circuit signal applied by the control signal generator 56 to the switch SW.

[0184] For example, when the UV LED 11 is in an open state, no current flows through the node connected to the current detection unit 55. In this case, the control signal generation unit 56 generates a short-circuit signal to allow current to flow through the UV LED 11 and transmits it to the switch SW. However, because the UV LED 11 is in an open state, the current detection unit 55 cannot detect the current even when the switch SW is in a short-circuit state. Therefore, the control signal generation unit 56 continuously generates a short-circuit signal and transmits it to the switch SW.

[0185] The short circuit signal detector 530 detects the short circuit signal of the control signal generator 56 and transmits a corresponding signal to the fault signal generator 560. In this case, if the short circuit signal detector 530 detects the short circuit signal for a predetermined period of time or longer, the fault signal generator 560 can determine that the ultraviolet LED 11 is in an open state. Therefore, if the control signal generator 56 generates the short circuit signal for a predetermined period of time or longer, the fault signal generator 560 can generate and output a fault signal indicating a fault in the ultraviolet LED 11.

[0186] As described above, the LED driving module 50 of this embodiment can detect a fault in the ultraviolet LED 11 by detecting the control signal of the control signal generator 56 that controls the switch SW and determining the type of the control signal and the time the control signal is applied to the switch SW.

[0187] FIG. 9 is a block diagram showing a simplified system of an ultraviolet LED device according to one embodiment of the present invention.

[0188] Referring to FIG. 9, a UV LED device system 1000 according to an embodiment may include a main module 1100 and an LED driving module 60.

[0189] The main module 1100 may be a module that controls the overall operation of a product to which the ultraviolet LED 11 and the LED driving module 60 are applied.

[0190] In the ultraviolet LED device system 1000 according to this embodiment, the main module 1100 can include a main control unit 1101 and an LED power generation unit 1102 .

[0191] The main control unit 1101 can control the overall operation of the product. The main control unit 1101 can generate signals for various operations of the product. The main control unit 1101 can also transmit power required for each component of the product to operate to each component. The main control unit 1101 can also supply power to the LED power generation unit 1102.

[0192] The LED power generation unit 1102 can generate LED driving power necessary for operating the UV LEDs 11 and the LED driving module 60. For example, the LED power generation unit 1102 can convert AC power supplied from the main control unit 1101 into DC power to generate LED driving power. The LED power generation unit 1102 can also include a filter for blocking noise, a power factor compensation circuit for compensating the power factor of the power supply, etc.

[0193] The driving power generated by the LED power generation unit 1102 may be transmitted to the LED driving module 60 .

[0194] The LED driving module 60 of this embodiment can be any one of the LED driving modules 10, 20, 30, 40, and 50 of the first to fifth embodiments described with reference to FIGS.

[0195] The LED driving module 60 supplies the driving power received from the LED power generation unit 1102 to the ultraviolet LEDs 11, thereby promoting the emission of ultraviolet light from the ultraviolet LEDs 11. The LED driving module 60 can also supply driving power not only to the ultraviolet LEDs 11 but also to other components.

[0196] The LED driving module 60 may include a constant current unit 12 for stable driving of the ultraviolet LED 11 and a failure detection unit 63 for detecting a failure of the ultraviolet LED 11 .

[0197] When a fault such as overheating, short circuit, or open circuit occurs in the ultraviolet LED 11, the fault detector 63 generates a fault signal to notify the fault and transmits the signal to the main controller 1101.

[0198] When the main control unit 1101 receives a fault signal from the fault detection unit 63, it can output a corresponding signal so that it can be visually or audibly confirmed outside the product. For example, the main control unit 1101 can notify the user of a fault in the ultraviolet LED 11 through a display device installed in the product. In addition, the main control unit 1101 can notify the user of a fault in the ultraviolet LED 11 by outputting a notification sound through a speaker installed in the product.

[0199] For example, the LED driving module 60 of this embodiment may be the LED driving module 20 according to the second embodiment of Fig. 5. In this case, the fault detection unit 63 of the LED driving module 60 may transmit the signals output via the first to third fault signal output terminals (27, 28, and 29 of Fig. 5) to the main control unit 1101.

[0200] The main control unit 1101 can determine the state of the ultraviolet LED 11 by combining the signals received from the first to third fault signal output terminals (27, 28, and 29 in FIG. 5) of the fault detection unit 63. For example, the main control unit 1101 can determine whether the ultraviolet LED 11 has a single or multiple problems out of abnormal heat generation, short circuit, and open circuit.

[0201] The main control unit 1101 can output a signal to the outside of the product through a device installed in the product so that the defect of the ultraviolet LED 11 corresponding to the result of each output terminal of the defect detection unit 63 can be recognized visually or audibly.

[0202] FIG. 10 is a block diagram showing a simplified system of an ultraviolet LED device according to another embodiment of the present invention.

[0203] The ultraviolet LED device system 2000 according to this embodiment may include a main module 2100 and an LED driving module 70 .

[0204] The ultraviolet LED device system 2000 of this embodiment differs from the ultraviolet LED device system 1000 of FIG. 9 in that the LED power supply generating unit 74 is included in the LED driving module 70.

[0205] The LED driving module 70 of this embodiment can convert AC power supplied from the main control unit 1101 into DC power. That is, the LED driving module 70 of this embodiment can include an LED power generation unit 74. The LED power generation unit 74 of the LED driving module 70 can convert the power supplied from the main control unit 1101 of the main module 2100 into driving power necessary for the ultraviolet LEDs 11 and other components to operate.

[0206] The LED device system 2000 of this embodiment is characterized in that the LED driving module 70 includes an LED power supply generating unit 74, and other features of each component are the same as those of the ultraviolet LED device system 1000 of FIG.

[0207] The LED driving modules described through various embodiments of the present invention may be applied to small products equipped with a single UV LED.

[0208] The LED driving module according to each embodiment of the present invention may include a defect detector that can detect defects in the UV LEDs. Thus, the LED driving module can detect various defects that may occur in the UV LEDs and generate a signal that can determine the specific type of defect.

[0209] Furthermore, according to the embodiments of the present invention, the LED driving module may implement the defect detection unit with a simple circuit, thereby minimizing an increase in module size. Therefore, the LED driving module according to the embodiments of the present invention may generate a signal indicating a defect in the UV LED while maintaining a size suitable for a small product.

[0210] As described above, the present invention has been described in detail by way of embodiments with reference to the accompanying drawings. However, the above-described embodiments are merely preferred examples of the present invention, and therefore the present invention should not be understood as being limited to the above-described embodiments. The scope of the present invention should be understood by the appended claims and their equivalents.

Claims

1. 1. An LED driving module having a single ultraviolet LED, a defect detection unit for detecting a defect in the ultraviolet LED; The failure detector includes a connection status detector that detects the connection status of the UV LED. The connection state detector outputs a fault signal from a fault signal output terminal when a fault occurs in the ultraviolet LED due to a short circuit or an open circuit.

2. The LED driving module of claim 1 , wherein the connection state detector comprises a connection detection switch that is turned on and off in response to a voltage of a node connected to the UV LED.

3. The node connected to the UV LED is connected to an anode terminal of the UV LED, The connection detection switch is a first terminal to which a voltage corresponding to the voltage of the node that turns on and off the connection detection switch is applied; a second terminal connected to the fault signal output terminal; The LED driving module of claim 2 , further comprising: a third end coupled to ground.

4. The fault signal output terminal is a first fault signal output terminal for outputting a first fault signal when the ultraviolet LED is in a short-circuit state; The LED driving module according to claim 3 , further comprising: a second fault signal output terminal for outputting a second fault signal when the ultraviolet LED is in an open state.

5. the first fault signal output terminal is connected to a node connecting the second terminal of the connection detecting switch and one terminal of a resistor; The second fault signal output terminal is connected to a node connecting two resistors in series between the anode terminal of the UV LED and ground, The LED driving module of claim 4 , wherein the other end of the resistor connected to the second end of the connection sensing switch is connected to ground.

6. The LED driving module of claim 3 , wherein the defect detector further comprises a heat detector for detecting a heat generation state of the ultraviolet LED.

7. The heat detection unit includes a thermal resistor whose resistance value changes depending on the ambient temperature, and a heat detection switch connected to the thermal resistor. The thermal resistor is connected to an anode terminal of the UV LED, The LED driving module of claim 6 , wherein the heat sensing switch is turned on and off by receiving a voltage that varies depending on the resistance value of the thermal resistor.

8. The heat sensing switch is a first terminal for receiving a voltage that varies depending on the resistance value of the thermal resistor; a second terminal connected to the fault signal output terminal; The LED driving module of claim 7 , further comprising: a third end coupled to ground.

9. The fault signal output terminal is a first fault signal output terminal for outputting a first fault signal when the ultraviolet LED is in a short-circuit state; a second fault signal output terminal for outputting a second fault signal when the ultraviolet LED is in an open state; The LED driving module according to claim 8 , further comprising: a third fault signal output terminal for outputting a third fault signal when the ultraviolet LED is in an overheated state.

10. the first fault signal output terminal is connected to a node connecting the second terminal of the connection detecting switch and one terminal of a resistor; The second fault signal output terminal is connected to a node connecting two resistors in series between the anode terminal of the UV LED and ground, the third fault signal output terminal is connected to a node connecting the second terminal of the heat sensing switch and one terminal of a resistor; The LED driving module of claim 9 , wherein the other end of the resistor connected to the second end of the connection sensing switch and the other end of the resistor connected to the second end of the heat sensing switch are each connected to ground.

11. The connection status detection unit an open detection unit that detects an open state of the ultraviolet LED; The LED driving module according to claim 2 , further comprising: a short circuit detector that detects a short circuit state of the ultraviolet LED.

12. Each of the open detection unit and the short detection unit is an amplifier that compares a reference voltage with an input voltage; 12. The LED driving module of claim 11, further comprising: at least one switch that is turned on and off by the output signal of the amplifier.

13. The opening detection unit includes an opening detection switch, The open detection switch is a first terminal for receiving a voltage for turning on or off a switch according to a signal output from the amplifier of the open detector; a second terminal connected to the fault signal output terminal; The LED driving module according to claim 12 , further comprising: a third terminal through which the current input via the first terminal passes when the open detection switch is in an on state.

14. the short circuit detection unit includes a short circuit detection switch, The short circuit detection switch is a first terminal for receiving a voltage for turning on or off a switch according to a signal output from an amplifier of the short circuit detector; a second terminal connected to the fault signal output terminal; The LED driving module according to claim 12 , further comprising: a third terminal through which the current input via the first terminal passes when the short-circuit detection switch is in an on state.

15. The LED driving module according to claim 11 , wherein the fault signal output terminal outputs a normal signal when the ultraviolet LED is in a normal state.

16. The LED driving module according to claim 15 , wherein the fault signal is a voltage lower than that of the normal signal.

17. further comprising a Zener diode having one end connected to the fault signal output terminal and the other end connected to ground; The LED driving module according to claim 15 , wherein the normal signal is a Zener voltage.

18. a current detector for detecting a current supplied to the ultraviolet LED; a control signal generator that generates and outputs a signal to control a switch according to the current value sensed by the current sensor, the control signal generation unit outputs a short-circuit signal to turn on the switch and an open signal to turn off the switch to the switch; the connection state detection unit detects the short signal and the open signal output from the control signal generation unit to the switch; The LED driving module of claim 1 , wherein the fault detector generates and outputs a fault signal when the short-circuit signal or the open-circuit signal detected by the connection state detector is detected for a predetermined time or longer.

19. The defect detector further includes a heat detector configured to detect a temperature of the ultraviolet LED or a temperature around the ultraviolet LED, The LED driving module of claim 18 , wherein the fault detector generates and outputs a fault signal when the temperature detected by the heat detector is equal to or higher than a preset temperature.

20. The LED driving module according to claim 1 , further comprising a constant current unit for supplying a constant current to the ultraviolet LED.

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