Abstract:
A display apparatus, a power supply apparatus and a power supply method are provided. The display apparatus display apparatus includes: a signal receiving unit which receives an image signal; a signal processing unit which processes the image signal; a display unit which displays an image based on the image signal processed by the signal processing unit; and a power supply unit which receives AC power and supplies operation power to the display unit. The power supply unit includes a discharging circuit part which includes a discharging element which discharges the power supply unit to remove a residual voltage from the power supply unit when the AC power is suspended, the discharging circuit part preventing the discharging element from consuming power when the AC power is input. It is possible to minimize wasteful power consumption caused by a discharging element provided to guarantee user&#39;s safety against a residual voltage.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority from Korean Patent Application No. 10-2009-0101303, filed on Oct. 23, 2009 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference. 
       BACKGROUND 
       [0002]    1. Field 
         [0003]    Methods and devices consistent with the exemplary embodiments relate to a display apparatus, a power supply apparatus and a power supply method thereof, and more particularly, to minimizing wasteful power consumption generated in a discharging device which discharges a residual voltage when AC power stops being supplied. 
         [0004]    2. Description of the Related Art 
         [0005]    A display apparatus such as a TV or the like is equipped with a power supply unit, for example, a switched-mode power supply (SMPS), for supplying operation power. Such a power supply unit converts commercial utility AC power into operation power of different levels required for various components of the display apparatus. 
         [0006]    A typical power supply unit includes circuit elements, for example, capacitors used for AC filtering, which are charged with a considerable voltage in normal operation. Accordingly, in order to prevent a user from being electrically shocked by the charged voltage (hereinafter also referred to as “residual voltage”), when the user unplugs a power cord, the power supply unit is provided with a discharging resistor for discharging the residual voltage. 
         [0007]    However, in the related art, since such a discharging resistor is constantly connected in the power supply unit, a discharged current may flow through the discharging resistor not only when the discharging resistor protects the user who unplugs the power cord, but also when the AC power is normally supplied to the components of the display apparatus, which may result in wasteful power consumption. 
         [0008]    More particularly, the AC power is supplied to the power supply unit even when the display apparatus is in a standby mode to minimize power consumption. Since the display apparatus is not normally operated in the standby mode, a significant amount of power is wasted. 
         [0009]    Such wasteful power consumption caused by the discharging resistor may occur in not only the display apparatus but also various forms of electronic devices with the above-mentioned power configuration. 
       SUMMARY 
       [0010]    Accordingly, one or more exemplary embodiments provide a display apparatus, a power supply apparatus and a power supply method thereof, which are capable of minimizing wasteful power consumption caused by a discharging element provided to guarantee a user&#39;s safety against a residual voltage when a user unplugs a power cord. 
         [0011]    Additional aspects will be set forth in part in the description which follows and, in part, will be apparent to one skilled in the art from the description, or may be learned by practice of the exemplary embodiments. 
         [0012]    The foregoing and/or other aspects may be achieved by providing a display apparatus including: a signal receiving unit which receives an image signal; a signal processing unit which processes the image signal received by the signal receiving unit; a display unit which displays an image based on the image signal processed by the signal processing unit; and a power supply unit which receives AC power and supplies operation power to the display unit, wherein the power supply unit includes a discharging circuit part which includes a discharging element which allows the power supply unit to discharge a residual voltage therefrom when the AC power is suspended, the discharging circuit part preventing the discharging element from consuming power when the AC power is input. 
         [0013]    The discharging circuit part may further include a first switching part which regulates a flow of current passing through the discharging element; and a switch control part which controls the first switching part to prevent the current from flowing through the discharging element when the AC power is input. 
         [0014]    The switch control part may include a voltage charging part which is charged with a turn-on voltage to turn on the first switching part; a second switching part which regulates a discharging path of the turn-on voltage charged in the voltage charging part; and an RC circuit part which turns on the second switching part so that the turn-on voltage charged in the voltage charging part can be discharged when the residual voltage is a DC voltage. 
         [0015]    The RC circuit part may switch the second switching part so that the first switching part can be turned off by the turn-on voltage of the voltage charging part in a standby mode for power saving. 
         [0016]    The discharging circuit part may further include a first diode and a second diode which are respectively provided on discharging paths of the power supply unit in association with a positive voltage and a negative voltage of the AC power, respectively. 
         [0017]    The power supply unit may further include an AC filter part which filters the AC power, and the discharging element may allow the AC filter part to discharge the residual voltage therefrom. 
         [0018]    The foregoing and/or other aspects may be achieved by providing a power supply apparatus for an electronic apparatus, including: an AC filter part which receives and filters AC power; a rectifier part which rectifies an output current of the AC filter part; a switching circuit part which converts an output voltage of the rectifier part into an operation voltage of the electronic apparatus; and a discharging circuit part which allows a discharging element which discharges the AC filter part to discharge a residual voltage therefrom when the AC power is suspended, the discharging circuit part preventing the discharging element from consuming power when the AC power is input. 
         [0019]    The discharging circuit part may further include: a first switching part which regulates a flow of current passing through the discharging element; and a switch control part which controls the first switching part to prevent the current from flowing through the discharging element when the AC power is input. 
         [0020]    The switch control part may include: a voltage charging part which is charged with a turn-on voltage to turn on the first switching part; a second switching part which regulates a discharging path of the turn-on voltage charged in the voltage charging part; and an RC circuit part which turns on the second switching part so that the turn-on voltage charged in the voltage charging part can be discharged when the residual voltage is a DC voltage. 
         [0021]    The RC circuit part may control the second switching part so that the first switching part can be turned off by the turn-on voltage of the voltage charging part in a standby mode for power saving. 
         [0022]    The power supply unit may further include a first diode and a second diode which are respectively provided on discharging paths of the AC filter part in association with a positive voltage and a negative voltage of the AC power, respectively. 
         [0023]    The foregoing and/or other aspects may be achieved by providing a power supplying method of receiving AC power and supplying operation power to an electronic apparatus, including: checking whether the AC power is input; and allowing a power supply unit to discharge a residual voltage therefrom using a discharging element when the AC power is suspended, and preventing the discharging element from consuming power when the AC power is input. 
         [0024]    The preventing may include preventing a current from flowing through the discharging element when the AC power is input. 
         [0025]    The preventing may include preventing the current from flowing through the discharging element in response to conversion of the residual voltage of the power supply unit into a DC voltage. 
         [0026]    The preventing may include preventing the current from flowing through the discharging element in a standby mode for power saving. 
         [0027]    The allowing may include allowing the power supply unit to discharge the residual voltage therefrom along different discharging paths in association with a positive voltage and a negative voltage of the AC power, respectively. 
         [0028]    According to one or more exemplary embodiments, when operation power is supplied to an electronic apparatus such as a display apparatus or the like, it is possible to minimize wasteful power consumption caused by a discharging element provided to guarantee a user&#39;s safety against a residual voltage when a user unplugs a power cord. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0029]    The above and/or other aspects will become apparent and more readily appreciated from the following description of the exemplary embodiments, taken in conjunction with the accompanying drawings, in which: 
           [0030]      FIG. 1  is a block diagram showing a configuration of a display apparatus according to one exemplary embodiment; 
           [0031]      FIG. 2  is a circuit diagram showing a configuration of a power supply unit in the display apparatus of  FIG. 1 ; 
           [0032]      FIGS. 3 and 4  are diagrams showing a discharging path of a residual voltage in the power supply unit of  FIG. 2 ; and 
           [0033]      FIG. 5  is a flow chart showing an operation of the display apparatus of  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
       [0034]    Reference will now be made in detail to the exemplary embodiments, which are illustrated in the accompanying drawings, so that those in the art can easily practice the exemplary embodiments. The exemplary embodiment disclosed herein are not to be construed as limiting, but may be implemented in different forms. 
         [0035]    In the following exemplary embodiments, for the purpose of clarity, the same components are denoted by the same reference numerals throughout the drawings, and explanation thereof will be representatively given in a first exemplary embodiment but will be omitted in other exemplary embodiments. 
         [0036]      FIG. 1  is a block diagram showing a configuration of a display apparatus  1  according to an exemplary embodiment. 
         [0037]    The display apparatus  1 , which may be implemented by a TV or the like, receives and processes image signals and displays images based on the processed image signals. As shown in  FIG. 1 , the display apparatus  1  includes a signal receiving unit  11 , a signal processing unit  12 , a display unit  13 , a communication unit  14 , a user input unit  15 , a storing unit  16  and a control unit  17 . 
         [0038]    The signal receiving unit  11  receives an image signal. The image signal received by the signal receiving unit  11  includes a broadcasting signal such as a DTV signal and a cable broadcasting signal. In this case, the signal receiving unit  11  may tune and receive a broadcasting signal of a channel selected by a user under control of the control unit  17 . In addition, the image signal received by the signal receiving unit  11  may further include signals which are output from imaging devices such as a DVD, BD and the like. Further, although not shown, the signal receiving unit  11  may receive an audio signal for audio output, a data signal for data output, and other signals. In this exemplary embodiment, the image signal, the audio signal and the data signal may be altogether received as a single signal. 
         [0039]    The signal processing unit  12  performs a predetermined signal processing for the image signal received by the signal receiving unit  11  so that an image can be displayed on the display unit  13 . The image processing performed by the signal processing unit  12  includes decoding, image enhancing, scaling, and so on. In addition, the signal processing unit  12  may perform processing for the voice signal and the data signal received by the signal receiving unit  11 . 
         [0040]    The display unit  13  displays the image based on the image signal processed by the signal processing unit  12 . The display unit  13  may display the image using an LCD scheme. In this case, although not shown, the display unit  13  may include an LCD panel, a panel driver, a backlight and so on. The display unit  13  may further display data information included in the data signal processed by the signal processing unit  12 . 
         [0041]    In addition, the display apparatus  1  may further include an audio output unit such as a speaker which can output an audio based on the audio signal processed by the signal processing unit  12 . 
         [0042]    The communication unit  14  communicates with external communication devices (not shown) through a network such as Internet or the like. In addition, the communication unit  14  may communicate with external communication devices (not shown) using a local area network system such as Bluetooth or the like. The communication unit  14  may transmit/receive information to/from a counterpart communication device under control of the control unit  17 . The information transmitted from the counterpart communication device to the communication unit  14  may include at least one of an image, audio and data which may be output through the display unit  13  and the like after being subjected to their respective proper process. 
         [0043]    The user input unit  15  may be implemented by, for example, a remote controller, a manipulation panel or the like for receiving an input from a user. The user input unit  15  may include an input key for selecting power-on/off of the display apparatus  1 . The user input received by the user input unit  15  is delivered to the control unit  17 . 
         [0044]    The storing unit  16  may be implemented by a nonvolatile memory, for example, a flash memory, a hard disk or the like for storing data and information to be used in the display apparatus  1 . 
         [0045]    The control unit  17  controls various components of the display apparatus  1  and may include a firmware as a control program and a CPU and a RAM for executing the firmware. 
         [0046]    The display apparatus  1  may further include a power supply unit  18  for supplying operation power to various components such as the display unit  13  and so on, as shown in  FIG. 1 . The power supply unit  18  receives commercial AC power and converts it into various levels of power required to operate the various components. In  FIG. 1 , detailed paths for the supply of power from the power supply unit  18  to the various components will be omitted for the sake of convenience. 
         [0047]    In one exemplary embodiment, the power supply unit  18  may further include a discharging circuit part  185 . The discharging circuit part  185  includes a discharging element (see  61  in  FIG. 2 ) for discharging a residual voltage remaining in the power supply unit  18  in response to possible suspension of the AC power. The discharging element  61  serves to prevent a user from being electrically shocked by the residual voltage, for example when a power cord (see  31  in  FIG. 2 ) is unplugged during operation of the apparatus. In addition, in one exemplary embodiment, the discharging circuit part  185  can prevent the discharging element  61  from consuming power when the AC power is input, thereby minimizing wasteful power consumption. Hereinafter, the power supply unit  18  according to one exemplary embodiment will be described in more detail with reference to  FIGS. 2 to 4 . 
         [0048]      FIG. 2  is a circuit diagram showing a detailed configuration of the power supply unit  18  shown in  FIG. 1 . In this exemplary embodiment, as shown in  FIG. 2 , the power supply unit  18  may further include an AC filter part  181 , a rectifier part  182 , a power factor correction (PFC) circuit part  183  and a switching circuit part  184 . 
         [0049]    The AC filter part  181  filters input AC power to remove noise from the AC power. As shown in  FIG. 2 , the AC filter part  181  may include a first capacitor  32  across the power cord  31 , a first transformer  33 , a second capacitor  34 , a fourth capacitor  35  and a fifth capacitor  36 . In normal operation, the second capacitor  34  is charged with a predetermined level of voltage Vr. 
         [0050]    The rectifier part  182  rectifies an alternating current (AC) output from the AC filter part  181  to convert the AC into a direct current (DC). The rectifier part  182  may be implemented by, for example, a bridge diode  37 . 
         [0051]    The PFC circuit part  183  includes a smoothing capacitor  41  for smoothing a DC voltage output by the rectifier part  182 . In addition, the PFC circuit part  183  further includes an inductor  38 , a first diode  40 , a pair of feedback resistors  42  and  43 , a first FET  39  and a PFC IC  44 . The PFC IC  44  switches the first FET  39  with a predetermined frequency based on a voltage Vf fed back by the feedback resistors  42  and  43  to increase a voltage with which the smoothing capacitor  41  is charged, thereby increasing a power factor of the power supply unit  18 . 
         [0052]    The switching circuit part  184  converts a level of voltage output from the PFC circuit part  183  into an operation voltage Vo to be supplied to the display unit and so on. As shown in  FIG. 2 , the switching circuit part  184  includes a second transformer  47  coupled to an output stage of the PFC IC  44 , a second FET  46  which is coupled in series to a primary coil side of the second transformer  47  for regulating a flow of current, a control IC  45  which switches the second FET  46 , a second diode  48  which is coupled to a secondary coil side of the second transformer  47  for rectifying the output operation voltage Vo, and a sixth capacitor  49  which maintains a level of operation voltage Vo. The control IC  45  switches the second FET  46  such that the level of operation voltage Vo reaches a predetermined target value. The operation voltage Vo is a voltage required to operate the display part  13  and so on and its level is varied depending on which component is supplied with the operation voltage Vo. For example, the operation voltage Vo supplied with the control unit  17  such as a CPU or a microcomputer may be 5V or so. The number of operation voltages Vo may be one or more. If the number of operation voltages Vo is two or more, the switching circuit part  184  may further include the same components as or components similar to the secondary coil of the second transformer  47 , the second diode  48  and the sixth capacitor  49  for each operation voltage Vo. In this case, different levels of plural operation voltages Vo may supplied to different components. 
         [0053]    In one exemplary embodiment, the display apparatus  1  has a normal mode in which it operates normally such as displaying an image on the display unit  13  and a standby mode in which it consumes a minimum amount of power. The control IC  45  controls the second FET  46  so that a required level of operation voltage Vo can be supplied to a component required to be operated even in the standby mode, for example, a microcomputer (not shown) for performing a standby mode control. 
         [0054]    The PFC circuit part  183  can be operated in the normal mode without being operated in the standby mode. In this connection, the power supply unit  18  may further include a tertiary coil  50 , a third diode  51 , a seventh capacitor  52 , an eighth capacitor  53  and a power switch  64 . A predetermined voltage is induced to the tertiary coil  50  by the secondary coil of the second transformer  47 . The seventh capacitor  52  is charged with the voltage induced to the tertiary coil  50 . The power switch  64  regulates coupling between the eighth capacitor  53 , the third diode  51  and the seventh capacitor  52 . When the power switch  64  is closed, the voltage with which the seventh capacitor  52  is charged is delivered to the eighth capacitor  53  or the eighth capacitor  53  is charged with the voltage induced to the tertiary coil  50 . The eighth capacitor  53  is coupled to the PFC IC  44  to which the voltage of the eighth capacitor  53  is supplied as a PFC driving voltage Vcc. 
         [0055]    The power switch  64  remains opened in the standby mode. In this state, since the PFC driving voltage Vcc cannot be supplied to the PFC IC  44 , the PFC circuit part  183  remains turned off. On the other hand, when a user turns on the apparatus through the user input unit  15 , a corresponding power-on signal is delivered to the power switch  64  so as to close the power switch  64 . In this case, since the PFC driving voltage Vcc is supplied to the PFC IC  44 , the PFC circuit part  183  is normally operated. 
         [0056]    Hereinafter, the discharging circuit part  185  according to one exemplary embodiment will be described in detail. As shown in  FIG. 2 , the discharging circuit part  185  includes a discharging element  61 , a first discharging diode  54 , a second discharging diode  55  and a first switching element  62 . The discharging element  61  discharges the power supply unit  18  to remove a residual voltage therefrom when the power cord  13  is unplugged during the normal mode, i.e., when the AC power is suspended. In this exemplary embodiment, the discharging element  61  may be implemented by a resistor. In this exemplary embodiment, one end of the discharging element  61  is coupled to both ends of the second capacitor  34  of the AC filter part  181  via the first discharging diode  54  and the second discharging diode  55 , respectively. The other end of the discharging element  61  is grounded via the first switching element  62 . The first switching element  62  may be implemented by a FET. 
         [0057]    The first discharging diode  54  and the second discharging diode  55  have their respective anodes and cathodes whose directions are determined to allow a current to flow from the second capacitor  34  into the discharging element  61 . Accordingly, if the first switching element  62  remains turned on, a residual voltage Vr with which the second capacitor  34  was charged causes the current to flow into the discharging element  61  via the first discharging diode  54  or the second discharging diode  55 , i.e., the second capacitor  34  can be discharged to remove its residual voltage Vr therefrom. 
         [0058]      FIGS. 3 and 4  show a discharging path of the residual voltage Vr in the power supply unit  18  of  FIG. 2 . In  FIGS. 3 and 4 , other configurations which are out of the discharging path in the power supply unit  18  of  FIG. 2  are omitted for the sake of convenience. Since the AC power applied to the second capacitor  34  is alternate, a polarity of the residual voltage Vr with which the second capacitor  34  has the same cycle as the AC power and is instantaneously changed. 
         [0059]    First,  FIG. 3  shows a state where the residual voltage Vr of the second capacitor  34  has a (+) polarity in its upper side and a (−) polarity in its lower side. In this state, the second capacitor  34  is discharged to remove the residual voltage Vr therefrom through a first discharging path A ranging from a ground of the bridge diode  37 , through the bridge diode  37 , the second capacitor  34 , the first discharging diode  54 , the discharging element  61 , the first switching element  62 , to a ground of the first switching element  62 . 
         [0060]    On the other hand,  FIG. 4  shows a state where the residual voltage Vr of the second capacitor  34  has a (−) polarity in its upper side and a (+) polarity in its lower side. In this state, the second capacitor  34  is discharged to remove the residual voltage Vr therefrom through a second discharging path B ranging from a ground of the bridge diode  37 , through the bridge diode  37 , the second capacitor  34 , the second discharging diode  55 , the discharging element  61 , the first switching element  62 , to a ground of the first switching element  62 . 
         [0061]    Referring again to  FIG. 2 , a configuration of controlling the first switching element  62  such that a current flows or not through the discharging element  61  will be described in detail. As shown in  FIG. 2 , in this exemplary embodiment, the discharging circuit part  185  may further include a ninth capacitor  60  and a fourth resistor  59 . The ninth capacitor  60  has one end coupled to a gate terminal of the first switching element  62  and the other end grounded. The one end of the ninth capacitor  60  is also coupled to a cathode of the third diode  51  via the fourth resistor  59 . Accordingly, the ninth capacitor  60  can be charged with a voltage supplied from the third diode  51 . The switching element  62  is operated depending on a level of voltage Vg with which the ninth capacitor  60  is charged. Specifically, if the voltage Vg with which the ninth capacitor  60  is charged is larger than an operation threshold voltage of the first switching element  62 , the first switching element  62  is turned on. On the contrary, if the voltage Vg with which the ninth capacitor  60  is charged is smaller than the operation threshold voltage of the first switching element  62 , the first switching element  62  is turned off. In one exemplary embodiment, the ninth capacitor  60  is a voltage charging element. 
         [0062]    In this exemplary embodiment, the discharging circuit part  185  may further include a tenth capacitor  56 , a third resistor  57 , a second switching element  58  and a fourth diode  63 . The second switching element  58  may be implemented by a transistor. A collector of the second switching element  58  is coupled to one end of the ninth capacitor  60  and an emitter of the second switching element  58  is grounded via the fourth diode  63 . Accordingly, if the second switching element  58  remains turned on, the ninth capacitor  60  is discharged to remove its voltage Vg therefrom via the second switching element  58  and the fourth diode  63 . 
         [0063]    The tenth capacitor  56  has one end coupled to cathodes of the first discharging diode  54  and the second discharging diode  55  and the other end coupled to one end of the third resistor  57 . In addition, a base of the second switching element  58  is coupled to the other end of the tenth capacitor  56  and the other end of the third resistor  57  is grounded. The second switching element  58  is operated depending on a level of voltage Vb applied to the third resistor  57 . Specifically, if the voltage Vb applied to the third resistor  57  is larger than an operation threshold voltage of the second switching element  58 , the second switching element  58  is turned on. On the contrary, if the voltage Vb applied to the third resistor  57  is smaller than the operation threshold voltage of the second switching element  58 , the second switching element  58  is turned off. In one exemplary embodiment, a combination of the ninth capacitor  60 , the fourth resistor  59 , the tenth capacitor  56 , the third resistor  57 , the second switching element  58  and the fourth diode  63  constitutes a switch control part. In addition, in one exemplary embodiment of the present invention, a combination of the tenth capacitor  56  and the third resistor  57  constitutes an RC circuit part. 
         [0064]    A process of discharging the second capacitor  34  to remove the residual voltage Vr therefrom or preventing it from being discharged depending on whether or not the AC power is input is as follows. First, when the power cord  31  is plugged in to input the AC power, a current by the AC power is supplied through the tenth capacitor  56 . In this case, since the voltage Vb applied to the third resistor  57  is varied with the same period as the AC power and its level passes above or below the operation threshold voltage of the second switching element  58  at the same period, the second switching element  58  remains turned on or alternates between turn-on and turn-off. With the second switching element  58  turned on, the ninth capacitor  60  charged with the voltage Vg is discharged via the second switching element  58 . Accordingly, since the level of voltage Vg with which the ninth capacitor  60  is charged cannot reach the operation threshold voltage of the first switching element  62 , the first switching element  62  is turned off. This results in prevention of current from flowing into the discharging element  61  and prevention of the second capacitor  34  charged with the residual voltage Vr from being discharged. 
         [0065]    Accordingly, when the AC power is input, it is possible to prevent wasteful power consumption from being generated due to the discharging element  61  by preventing the second capacitor  34  charged with the residual voltage Vr from being discharged. In particular, it is possible to make an effective standby power design to minimize power consumption for the standby mode or the like. 
         [0066]    On the other hand, when the power cord  31  is unplugged to suspend the AC power, the residual voltage Vr of the second capacitor  34  has a DC level. Such a DC residual voltage Vr is blocked by the tenth capacitor  56  and thus the voltage Vb applied to the third resistor  57  becomes smaller than the operation threshold voltage of the second switching element  58 . Accordingly, the second switching element  58  is turned off and the ninth capacitor  60  charged with the voltage Vg can be sufficiently charged up to a level higher than the operation threshold voltage of the first switching element  62 . Accordingly, the first switching element  62  is turned on to allow a current to flow into the discharging element  61  and discharge the second capacitor  34  charged with the residual voltage VR. 
         [0067]    This ensures safety of a user by discharging the second capacitor  34  charged with the residual voltage VR using the discharging element  61  even when the power cord  31  is unplugged. 
         [0068]      FIG. 5  is a flow chart showing an operation of the discharging circuit part  185  according to one exemplary embodiment. First, the discharging circuit part  185  checks whether or not AC power is input ( 501 ). If it is determined that the AC power is input ( 502 -Y), the discharging element  61  is prevented from consuming power by preventing the second capacitor  34  charged with the residual voltage Vr from being discharged ( 504 ). On the contrary, if it is determined that the AC power is suspended ( 502 -N), the second capacitor  34  charged with the residual voltage Vr is discharged via the discharging element  61  ( 503 ). 
         [0069]    Although a few exemplary embodiments have been shown and described, it will be appreciated by those skilled in the art that changes may be made in these exemplary embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents. For example, although it has been illustrated in the above exemplary embodiments that the power supply unit  18  is implemented as one component of the display apparatus  1 , a separated power supply device (not shown) having the same configuration as or configuration similar to the power supply unit  18  may be implemented to supply the operation power to the display apparatus according to different exemplary embodiments. Further, a target to which the operation power may be supplied from the power supply device according to one exemplary embodiment may be not only the display apparatus but also other different types of electronic apparatuses.