Abstract:
Disclosed is a power supply device including a wired controller receiving AC power to generate a driving voltage, and outputting a lighting driving signal, a wireless controller wirelessly receiving a lighting control signal and outputting the lighting control signal to the wired controller, and a standby power supply unit receiving a reference standby voltage based on the driving voltage, storing the reference standby voltage, and supplying the reference standby voltage to the wireless controller as standby power. In the lighting control device based on wired/wireless communication, the power is always obtained from the super capacitor to turn on the wireless controller, so that the turn-on state of the power generator of the wired controller is not always required. The power consumption is reduced by reducing the standby power.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit under 35 U.S.C. §119 of Korean Patent Application No. 10-2012-0095257, filed Aug. 29, 2012, which is hereby incorporated by reference in its entirety. 
     BACKGROUND 
     The disclosure relates to a power supply device for a light emitting device. 
     A light emitting diode device (LED) is a light emitting semiconductor serving as a semiconductor PN junction device to convert electrical energy into light energy. The LED is a device to emit light through the recombination between electrons and holes at the PN junction region or the active layer by applying current to a compound semiconductor terminal. 
     The lighting apparatus employing the LED as a lighting source is controlled through both of wired control and wireless control. 
     In this case, when the wireless control is performed, as well as the wired control performed by receiving basic power through a cable, a wireless module is required to make wireless communication. 
     Since the wireless module receives a wireless control signal applied from the external device to generate the lighting control signal, the wireless module must be always maintained at an on-state. 
     Therefore, the power is always required to maintain the on-state of the wireless module, and the power may be obtained from power applied through the wired control. 
     However, if the wired control module is always maintained at the on-state for the wireless control, the great quantity of standby power is consumed. 
     To this end, a scheme employing a backup-battery has been suggested. Since the backup-battery has the endurance weaker than that of a light emitting diode, problems may be caused in the replacement of the backup-battery. 
     BRIEF SUMMARY 
     The embodiment provides a power supply device for a light emitting diode device capable of reducing the standby power for the wireless control. 
     According to the embodiment, there is provided a power supply device including a wired controller receiving AC power to generate a driving voltage, and outputting a lighting driving signal, a wireless controller wirelessly receiving a lighting control signal and outputting the lighting control signal to the wired controller, and a standby power supply unit receiving a reference standby voltage based on the driving voltage, storing the reference standby voltage, and supplying the reference standby voltage to the wireless controller as standby power. 
     In addition, according to the embodiment, there is provided a lighting apparatus including a lighting unit including a plurality of lighting emitting diodes, and a lighting control unit receiving AC power, and receiving a lighting control signal for the lighting unit through a wired scheme or a wireless scheme to output a lighting driving signal to the lighting unit. The lighting control unit includes a capacitor storing a reference standby voltage generated from on the AC power and supplying the reference standby voltage as standby power to wirelessly receive the lighting control signal. 
     Meanwhile, according to the embodiment, there is provided a method of driving a lighting apparatus including a lighting unit including a plurality of lighting emitting diodes, and a lighting control unit receiving AC power, receiving a lighting control signal for the lighting unit through a wired scheme or a wireless scheme to output a lighting driving signal to the lighting unit, and including a capacitor storing a reference standby voltage generated from the AC power and supplying the reference standby voltage as standby power to wirelessly receive the lighting control signal. The method includes periodically checking a voltage level of the capacitor, charging the capacitor with the AC power if the voltage level of the capacitor is lower than a first reference voltage, and discharging the voltage of the capacitor as a voltage for standby power by cutting off the AC power if the voltage level of the capacitor is higher than a level of a second reference voltage. 
     As described above, according to the lighting control device based on wired/wireless communication of the present invention, the power is always obtained from the super capacitor to turn on the wireless controller, so that the turn-on state of the power generator of the wired controller is not always required. Accordingly, the power consumption can be reduced by reducing the standby power. In addition, the light emitting diode can be semipermanently realized according to the life span thereof by employing the super capacitor, so that the reliability of the operation of the wireless controller can be ensured. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a view showing a lighting apparatus according to the embodiment; 
         FIG. 2  is a block diagram showing the structure of a wired controller of  FIG. 1 ; 
         FIG. 3  is a block diagram showing the structure of a wireless controller of  FIG. 2 ; 
         FIG. 4  is a block diagram showing the structure of a standby power supply unit of  FIG. 3 ; 
         FIG. 5  is a flowchart showing the operation of a lighting control module of  FIG. 1 ; and 
         FIG. 6  is a detailed flowchart showing an initialization step of  FIG. 5 . 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, an exemplary embodiment of the disclosure will be described to be implemented by those skilled in the art in detail with reference to accompanying drawings. However, the disclosure can be variously modified, and not limited to the embodiment. 
     In the following description, when a predetermined part “includes” a predetermined component, the predetermined part does not exclude other components, but may further include other components if there is a specific opposite description. 
     According to a lighting control device including a wireless controller of the present invention, the lighting control device can be wirelessly controlled without always turning on a wired controller by employing an additional power unit to supply power for wireless control. 
     Hereinafter, a lighting apparatus  10  according to the embodiment of the disclosure will be described with reference to  FIGS. 1 to 4 . 
       FIG. 1  is a view showing the lighting apparatus  10  according to the embodiment,  FIG. 2  is a block diagram showing the structure of a wired controller  40  of  FIG. 1 , and  FIG. 3  is a block diagram showing the structure of a wireless controller  50  of  FIG. 2 .  FIG. 4  is a block diagram showing the structure of a standby power supply unit  60  of  FIG. 3 . 
     Referring to  FIG. 1 , the lighting apparatus  10  includes a lighting unit  30  and a lighting control unit  20 . 
     The lighting unit  30  includes a plurality of light emitting diodes, and the light emitting diodes may be connected to each other in series as shown in  FIG. 1 . Alternatively, the light emitting diodes may be connected to each other in parallel. 
     The lighting unit  30  may be provided in the form of a lamp by grouping the light emitting diodes. Alternately, the lighting unit  30  may include a light guide plate or a diffusion plate to serve as a surface light source. 
     In addition, the lighting unit  30  may include a plurality of light emitting diodes to represent a plurality of colors. For example, when the light emitting diode includes red, blue, and green light emitting diodes, the lighting unit  30  may adjust the color temperature by controlling an on/off-state and an on/off time of each light emitting diode. 
     The lighting control unit  20  generates a driving signal to control an on/off-state of the lighting unit  30 . 
     The driving signal for the lighting serves as a pulse signal, and the turn-on time of the light emitting diode is determined according to the pulse duty of the pulse signal. 
     The lighting control unit  20  includes the wired controller  40 , the wireless controller  50 , and the standby power supply unit  60 . 
     The wired controller  40  receives and converts reference AC voltage through a cable and generates driving voltage. The wired controller  40  receives a control signal through a cable and generates a lighting driving signal according to the control signal. 
     The wired controller  40  includes an AC-DC rectifying unit  41 , a wireless module power supply unit  43 , and an LED driving unit  45  as shown in  FIG. 2 . 
     The AC-DC rectifying unit  41  receives 110/220V AC voltage, and converts the AC voltage into driving voltage having a level to drive the lighting control unit  20 . 
     The driving voltage is DC voltage. The AC-DC rectifying unit  41  may include a rectifying circuit to convert AC into DC and a transformer to adjust a voltage level. 
     The rectifying circuit may include a bridge rectifier, and the transformer may include a typical transformer such as a flyback converter. 
     The LED driving unit  45  receives the driving voltage from the AC-DC rectifying unit  41  and operates by the driving voltage to generate a lighting driving signal having a level to turn on the light emitting diode of the lighting unit  30 . 
     The LED driving unit  45  may include a pulse width modulator, and may adjust the brightness of the light emitting diode according to the pulse duty rate. 
     The LED driving unit  45  may receive the driving voltage of 19V, but the embodiment is not limited thereto. 
     Meanwhile, the wired controller  40  includes the wireless module power supply unit  43 . 
     The wireless module power supply unit  43  receives the driving voltage from the AC-DC rectifying unit  41  and converts the driving voltage to generate wireless reference voltage used to generate the driving voltage for driving the wireless controller  50 . 
     The wireless reference voltage may be 3.6V. The value of the wireless reference voltage may vary depending on the specification of the wireless controller  50 . 
     The wireless module power supply unit  43  may include a DC-DC converter. 
     Meanwhile, the lighting control unit  20  includes the wireless controller  50 , such as a remote controller or a smart phone that is generally used, to control the lighting unit  30  by receiving a control signal through a wireless network. 
     The wireless controller  50  includes a wireless communication unit  51  connected to an antenna, an LED lighting control unit  53 , a power generating unit  55 , and a power control unit  57 . 
     The wireless communication unit  51  is connected to the antenna to transreceive a wireless control signal through a wireless network like a wireless device, preferably, a remote controller or a smart phone. 
     The wireless network may employ a short range communication scheme such as a ZigBee scheme or a Bluetooth scheme. Alternatively, the wireless network may include an RFID. 
     In addition, the wireless network may make communication by using WiFi. 
     The wireless communication unit  51  amplifies and demodulates a wireless control signal received through the wireless network to extract a base control signal from the wireless control signal. 
     The LED lighting control unit  53  receives the base control signal received therein from the wireless communication unit  51 , extracts dimming information and color temperature information, which is used to drive the lighting unit  30 , from the base control signal, and outputs the dimming information and the color temperature information to the LED driving unit  45 . 
     Meanwhile, the wireless communication unit  51  must be always turned on in order to receive the wireless control signal irregularly applied from the external device. 
     In other words, the wireless communication unit  51  operates at a sleep mode, which is a standby state to receive the wireless control signal, in addition to an active mode of receiving and processing the wireless control signal. 
     The wireless communication unit  51  must be always turned on in order to maintain the sleep mode. In this case, the wireless communication unit  51  requires standby power. 
     In order to apply the standby power for the turn-on state of the wireless communication unit  51 , the wireless controller  50  includes the power generating unit  55  and the power control unit  57 . 
     The power generating unit  55  receives the reference standby power supplied from the standby power supply unit  60 , and converts the reference standby power into the standby power having a level required at the sleep mode of the wireless communication unit  51 . 
     The power generating unit  55  may include a DC-DC converter. 
     Meanwhile, the power control unit  57  periodically senses the state of the standby power supply unit  60  to output a switching signal so that the wireless reference voltage of the wireless module power supply unit  43  is supplied to the wireless module power supply unit  43  according to the power levels of the standby power supply unit  60 . 
     The wireless controller  50  may further include a module control unit (not shown) to wholly control the operations of the wireless communication unit  51 , the power generating unit  55 , and the power control unit  57 . The module control unit may be realized by using a processor. 
     Meanwhile, referring to  FIG. 4 , the lighting control unit  20  further includes the standby power supply unit  60 . 
     The standby power supply unit  60  includes a switching unit  61 , which is used to supply the AC power to the wired controller  40  and to supply the wireless reference voltage to the standby power supply unit  60 , and the storage unit  63  to receive and store the wireless reference voltage transmitted through the switching unit  61 . 
     The storage unit  63  includes a super capacitor. The super capacitor has a large capacity, and is semipermanently available. 
     The super capacitor of the storage unit  63  repeats a cycle of receiving the wireless reference power through the switching unit  61 , being charged with the wireless reference power, and then being discharging so that the power is supplied to the power generating unit  55  of the wireless controller  50 . 
     The super capacitor has a charge capacity in the range of 3.6 V to 5.5 V. 
     The switching unit  61  includes relay switches S1 and S2. In particular, the switching unit  61  includes at least two switches S1 and S2. 
     The switching unit  61  includes the first switch S1 used to supply the AC power to the AC-DC rectifying unit  41  of the wired controller  40  and the second switch S2 used to supply the wireless reference power of the wireless module power supply unit  43  to the super capacitor. 
     The first and second switches S1 and S2 are turned on or turned off by receiving the switching signal from the power control unit  57 . The first and second switches S1 and S2 are simultaneously turned on or simultaneously turned off. 
     Hereinafter, the operation of generating the standby voltage of the lighting control unit  20  will be described with reference to  FIGS. 5 and 6 . 
     First, if the AC power is applied to the wired controller  40  so that the wired controller  40  starts to operate (step S 100 ), the entire system is initialized (step S 200 ). 
     The system initialization process may be performed as shown in  FIG. 6 . 
     In other words, hardware related to the standby power is initialized (step S 210 ). In other words, the wireless module power supply unit  43 , the power generating unit  55 , and the power control unit  57  are initialized. 
     Next, the PWM of the LED driving unit  45  is initialized so that the control signal may be received (step S 220 ). 
     Then, after the power control unit  57  initializes a relay control oscillator to generate the switching signal (step S 230 ), the power control unit  57  initializes the timer for checking the storage unit of the wireless control unit  50  (step S 240 ). Subsequently, the power control unit  57  initializes an AC-DC converter thereof (step S 250 ) to initialize a residual voltage level read out of the super capacitor. 
     Finally, the power control unit  50  initializes software related to the standby power so that the operation of generating the standby power can be started (step S 260 ). 
     If the initialization operation is terminated, the processor of the wireless module unit performs a main operation of generating the standby power (step S 300 ). 
     First, the wireless control unit  50  determines if an event for checking the storage unit  63  occurs (step S 310 ). 
     If the event for checking the storage unit  63  is periodically generated, the power control unit  57  checks the voltage of the super capacitor of the storage unit  63  (step S 320 ). In this case, if the event for checking the storage unit  63  does not occur, another event may be processed (step S 315 ). 
     The power control unit  57  detects the voltage level of the super capacitor to convert the voltage level into a predetermined level through the AC-DC converter (step S 321 ), and stores the converted voltage level as an ADC value (step S 323 ). 
     Next, the power control unit  57  charges or discharges the super capacitor depending on the stored ADC value (step S 330 ). 
     First, the power control unit  57  determines if the lighting unit  30  is turned off (step S 340 ). If the lighting unit  30  is turned off, the power control unit  57  senses the charged state of the super capacitor (step S 350 ). 
     If the super capacitor is fully charged, and the ADC value is greater than a Vd value (step S 360 ), the first and second switches S1 and S2 of the switching unit  61  are turned off (step S 370 ). 
     In this case, the Vd value may be 3.25V which is the minimum standby voltage required at the sleep mode of the wireless communication unit  51 . 
     If the first and second switches S1 and S2 of the switching unit  61  are turned off as described above, the wireless module power supply unit  43  is disconnected from the super capacitor, so that the super capacitor is maintained at a floating state. Accordingly, the charges stored in the super capacitor are discharged. 
     Meanwhile, if the lighting unit  30  is maintained at the on-state, the super capacitor is checked for the discharge state (step S 380 ). 
     If the super capacitor is at the discharge state, the first and second switches S1 and S2 of the switching unit  61  are simultaneously turned on so that the super capacitor is charged (step S 385 ). 
     Meanwhile, if the super capacitor is not charged in the state that the lighting unit is turned off, and if the ADC value is less than the Vt (step S 390 ), the first and second switches S1 and S2 of the switching unit  61  are turned on so that the super capacitor is charged (step S 395 ). 
     If the ADC value is greater than the Vt, the present state is maintained. 
     In this case, the Vt value may be 2.4 V, but the embodiment is not limited thereto. 
     The wireless communication unit  51  of the wireless control unit  50  may be maintained at the sleep mode for at least 20 minutes if the standby power is implemented from the voltage charged in the super capacitor. Accordingly, the period may be set within 20 minutes. 
     In addition, the voltage level of the super capacitor is periodically detected and the charging and discharging of the super capacitor are induced, thereby supplying the standby power to continuously maintain the sleep mode. 
     Although the exemplary embodiments of the present invention have been described, it is understood that the present invention should not be limited to these exemplary embodiments but various changes and modifications can be made by one ordinary skilled in the art within the spirit and scope of the present invention as hereinafter claimed.