Abstract:
There is provided a power supplying apparatus capable of determining whether to be normally operated by detecting whether a capacitor deteriorates with age based on a ripple voltage generated by switching of a primary side, the power supplying apparatus including a power supply unit switching input power to convert the input power into preset direct current (DC) power, a detecting unit setting a reference voltage based on the DC power of the power supply unit and comparing the reference voltage with a ripple voltage included in the DC power to detect a voltage level of the ripple voltage, and a controlling unit determining whether an abnormality has occurred according to a detection result of the detecting unit.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the priority of Korean Patent Application No. 10-2012-0141987 filed on Dec. 7, 2012, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a power supplying apparatus having a detectable useful life. 
     2. Description of the Related Art 
     Recently portable electronic devices have been implemented with systemization, digitization, wireless communications and multimedia capabilities, intelligence, complexity, and the like. Among them, as social interest in the implementation of multimedia capabilities has increased, small, portable multimedia devices have been prominent. 
     Among them, as mobile devices such as smartphones and a tablet personal computers (tablet PCs) have come to prominence as new information devices, new technology requirements for driving power supplying apparatuses such as an adapter for charging power in a battery of such an apparatus have increased. 
     In an existing driving power supplying apparatus, only standby power is regulated in public. However, as several functions such as touchscreens have been added to the mobile device, a situation in which the driving power supplying apparatus should significantly decrease an effect thereof on a main body during charging of a device has occurred. 
     Meanwhile, the power supplying apparatus as described above generally receives commercial alternating current (AC) power, converts the commercial AC power into direct current (DC) power appropriate for a device, and then supplies the DC power to the device, as disclosed in the following Related Art Document. Therefore, the power supplying apparatus includes various passive elements and active elements in order to convert and supply the power, such that a useful lifespan thereof is limited. In addition, when the useful lifespan of the power supplying apparatus ends, normal supplying of power from the power supplying apparatus is limited, such that the power may not be smoothly supplied to the device receiving the driving power from the power supplying apparatus. 
     RELATED ART DOCUMENT 
     (Patent Document 1) Korean Patent Laid-Open Publication No. 10-2004-0099489 
     SUMMARY OF THE INVENTION 
     An aspect of the present invention provides a power supplying apparatus capable of determining whether to be normally operated by detecting whether a capacitor deteriorates with age based on a ripple voltage generated by switching of a primary side. 
     According to an aspect of the present invention, there is provided a power supplying apparatus including: a power supply unit switching input power to convert the input power into preset direct current (DC) power; a detecting unit setting a reference voltage based on the DC power of the power supply unit and comparing the reference voltage with a ripple voltage included in the DC power to detect a voltage level of the ripple voltage; and controlling unit determining whether an abnormality has occurred according to a detection result of the detecting unit. 
     The power supply unit may include a smoothing unit having a capacitor smoothing the power generated by rectifying the input power. 
     The detecting unit may detect the voltage level of the ripple voltage caused by the capacitor of the smoothing unit. 
     The detecting unit may include: a first dividing resistor group dividing a voltage level of the DC power according to a first preset resistance ratio; a second dividing resistor group dividing a voltage level of the DC power according to a second preset resistance ratio; a first capacitor stabilizing the voltage level divided by the second dividing resistor group; and a comparator comparing the divided voltage level transferred from the first dividing resistor group and input to a negative terminal thereof and the divided voltage level transferred from the second dividing resistor group and input to a positive terminal thereof. 
     The detecting unit may further include a second capacitor stabilizing the voltage level divided by the first dividing resistor group. 
     The first capacitor may have capacitance higher than that of the second capacitor. 
     The detecting unit may include: a dividing resistor group dividing a voltage level of the DC power according to a preset resistance ratio; first and second diodes transferring respective voltage levels divided by the dividing resistor group to different paths; a first capacitor stabilizing the voltage level from the first diode; and a comparator comparing the voltage level from the second diode input to a negative terminal thereof and the voltage level from the first diode input to a positive terminal thereof. 
     The detecting unit may further include a second capacitor stabilizing the voltage levels divided by the dividing resistor group. 
     The power supply unit may include: a rectifying unit rectifying the input power; a converting unit switching the power smoothed by the smoothing unit and transforming the switched power according to a preset turns ratio; and a stabilizing unit stabilizing the transformed power from the converting unit to output the stabilized power. 
     The power supplying apparatus may further include an outputting unit switching an output of the DC power on or off according to a control of the controlling unit. 
     The power supplying apparatus may further include a display unit displaying whether the abnormality has occurred according to a control of the controlling unit. 
     According to another aspect of the present invention, there is provided a power supplying apparatus including: a power supply unit including a smoothing unit having a capacitor smoothing power generated by rectifying input power and switching the smoothed power to convert the smoothed power into preset DC power; a detecting unit setting a reference voltage based on the DC power of the power supply unit and comparing the reference voltage with a ripple voltage included in the DC power by the capacitor of the smoothing unit to detect a voltage level of the ripple voltage; and a controlling unit determining whether an abnormality has occurred according to a detection result of the detecting unit. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other aspects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a circuit diagram schematically showing a power supplying apparatus according to a first embodiment of the present invention; 
         FIG. 2  is a circuit diagram schematically showing a power supplying apparatus according to a second embodiment of the present invention; 
         FIG. 3  is a circuit diagram schematically showing a power supplying apparatus according to a third embodiment of the present invention; 
         FIG. 4  is a circuit diagram schematically showing a power supplying apparatus according to a fourth embodiment of the present invention; and 
         FIG. 5  is a graph showing signal waveforms of main components of the power supplying apparatus according to the embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, the shapes and dimensions of elements may be exaggerated for clarity, and the same reference numerals will be used throughout to designate the same or like elements. 
       FIGS. 1 through 4  are circuit diagrams schematically showing power supplying apparatuses according to first to fourth embodiments of the present invention, respectively. 
     Referring to  FIG. 1 , a power supplying apparatus  100  according to the first embodiment of the present invention may include a power supply unit  110 , a detecting unit  120 , and a controlling unit  130 , and further include an outputting unit  140 . 
     The power supply unit  110  may include a rectifying unit  111  rectifying input power Vin, a smoothing unit  112  including a capacitor C 1  smoothing the rectified power by the rectifying unit  111 , a converting unit  113  switching the smoothed power from the smoothing unit  112  and transforming the switched power to output the transformed power, and a stabilizing unit  114  stabilizing the power output from the converting unit  113  to output the stabilized power. 
     The input power Vin may be commercial alternating current (AC) power, and the rectifying unit  111  may be configured of a bridge diode to half-wave or full-wave rectify the input power Vin. 
     The capacitor C 1  of the smoothing unit  112  may be charged with the rectified power to smooth a waveform of the power. Therefore, a ripple voltage may be included in power output by a rear circuit. 
     The converting unit  113  may include a switch Q 1  switching the smoothed power, a switching controller  113   a  controlling a power switching operation of the switch Q 1 , and a transformer T having a primary winding receiving the switched power and a secondary winding electromagnetically coupled to the primary winding to form a preset turns ratio therewith and transforming the switched power to output the transformed power according to the turns ratio. 
     The stabilizing unit  114  may include a diode D 1  and a capacitor C 2  to stabilize the power output from the secondary winding of the transformer T. The ripple voltage caused due to the capacitor C 1  of the smoothing unit  112  may be transferred to a capacitor C 2  and included in DC power transferred to the rear circuit. 
     The detecting unit  120  may include a first dividing resistor group R 1  and R 2 , a second dividing resistor group R 3  and R 4 , a first capacitor C 3 , and a comparator OP, and further include a second capacitor C 4 . 
     Each of the first dividing resistor group R 1  and R 2  and the second dividing resistor group R 3  and R 4  may have a preset resistance ratio and divide the DC power from the stabilizing unit  114  according to the resistance ratio. 
     The first capacitor C 3  may stabilize the divided voltage from the second dividing resistor group R 3  and R 4  and input the stabilized voltage to a positive (+) terminal of the comparator OP, and the input voltage may be a reference voltage. 
     The first dividing resistor group R 1  and R 2  may divide the DC power from the stabilizing unit  114  according to the resistance ratio and input the divided voltage to a negative (−) terminal of the comparator OP. Therefore, a voltage level of the ripple voltage included in the DC power from the stabilizing unit  114  may be detected, and the comparator OP may compare a voltage level of the reference voltage with the voltage level of the ripple voltage included in the DC power. 
     To this end, the first capacitor C 3  may stabilize the divided voltage from the second dividing resistor group R 3  and R 4 , and capacitance of the first capacitor C 3  may be higher than that of the second capacitor C 4  in the case in which the second capacitor C 4  is further provided in order to decrease noise. 
     The controlling unit  130  may recognize whether the power is unstable due to deterioration with age of the capacitor C 1  according to a comparison result from the comparator OP and block the supplying of the power or allow a power abnormality to be displayed when it recognizes that the power is unstable. More specifically, when the capacitor C 1  deteriorates with age, a difference in voltage level between a maximum voltage and a minimum voltage of the ripple voltage may be high, and the controlling unit  130  may receive the comparison result of the comparator OP and determined that the DC power is unstable due the deterioration with age of the capacitor C 1  in the case in which the difference in voltage level between the maximum voltage and the minimum voltage of the ripple voltage is larger than a preset normal voltage level range. 
     The power supplying apparatus  100  according to the first embodiment of the present invention shown in  FIG. 1  may include the outputting unit  140 , and the outputting unit  140  may include a switch Q 2  switched on or off according to a control of the controlling unit  130  to supply or block the DC power. 
     A power supplying apparatus  200  according to the second embodiment of the present invention shown in  FIG. 2  may include a power supply unit  210  including a rectifying unit  211 , a smoothing unit  212 , a converting unit  213 , and a stabilizing unit  214 , a detecting unit  220 , and a controlling unit  230 . Since operations and functions of the above-mentioned components are the same as or similar to those of the power supply unit  110 , the detecting unit  120 , and the controlling unit  130  of the power supplying apparatus  100  according to the first embodiment of the present invention shown in  FIG. 1 , respectively, a detailed description thereof will be described. 
     However, the controlling unit  230  may recognize whether the power is unstable due to deterioration with age of the capacitor C 1  according to the comparison result from the comparator OP, and allowing a light emitting diode (LED) to emit light through a switch Q 3  of a display unit  250 , rather than stopping the output of the DC power when the DC power is determined to be unstable due to the deterioration with age of the capacitor C 1 , thereby displaying that the DC power is unstable to the outside. 
     In power supplying apparatuses  300  and  400  according to the third and fourth embodiments of the present invention shown in  FIGS. 3 and 4 , since configurations and functions of power supply units  310  and  410  including rectifying units  311  and  411 , smoothing units  312  and  412 , converting units  313  and  413 , and stabilizing units  314  and  414 , controlling units  330  and  430 , and an outputting unit  340  or a displaying unit  450  except for configurations and functions of detecting units  320  and  420  are the same as or similar to those of the power supplying apparatus  100  and  200  according to the first and second embodiments of the present invention shown in  FIGS. 1 and 2 , respectively, a detailed description thereof will be omitted. 
     Describing the detecting units  320  and  420  of the power supplying apparatuses  300  and  400  according to the third and fourth embodiments of the present invention shown in  FIGS. 3 and 4 , the detecting units  320  and  420  may include the dividing resistor group R 1  and R 2 , first and second diodes D 2  and D 3 , and the first and second capacitors C 3  and C 4 , and the comparator OP, respectively. 
     The dividing resistor group R 1  and R 2  may have a preset resistance ratio and divide the DC power from the stabilizing unit  314  or  414  according to the resistance ratio. 
     The first and second diodes D 2  and D 3  may transfer respective voltages divided by the dividing resistor group R 1  and R 2  to different paths, more specifically, a positive (+) terminal or a negative (−) terminal of the comparator OP. 
     The first capacitor C 3  may stabilize the voltage transferred from the first diode D 2  and transfer the stabilized voltage to the positive (+) terminal of the comparator OP, and the voltage from the second diode D 3  may be transferred to the negative (−) terminal of the comparator OP. A comparison result of the comparator OP may be transferred to the controlling unit  330  or  430 . Likewise, in the case in which the second capacitor C 4  is further provided in order to decrease noise, capacitance of the first capacitor C 3  may be larger than that of the second capacitor C 4 . 
       FIG. 5  is a graph showing signal waveforms of main components of the power supplying apparatus according to the embodiment of the present invention. 
     Referring to  FIG. 5  together with  FIG. 3  or  FIG. 4 , the voltage from the first capacitor C 3  may be set to a reference voltage, and a difference in voltage level between the maximum voltage and the minimum voltage of a ripple voltage from the second diode D 3  is transferred to the controlling unit  330  or  430 , such that the controlling unit  330  or  430  may determine whether the DC power is unstable due to the deterioration with age of the capacitor C 1 . 
     In  FIG. 5 , the ripple voltage from the second diode D 3  is shown. However, referring to  FIG. 1  or  FIG. 2 , the divided voltages of the first dividing resistance group R 1  and R 2  will be the same as the ripple voltage from the second diode D 3 . Therefore, the controlling unit  130  or  230  may determine whether the DC power is unstable due to the deterioration with age of the capacitor C 1 . 
     As set forth above, according to the embodiments of the present invention, whether a capacitor deteriorates with age is detected based on the ripple voltage generated by the switching of the primary side to thereby recognize whether the power supplying apparatus is normally operated, whereby the supplying of unstable power to a device can be prevented in advance. 
     While the present invention has been shown and described in connection with the embodiments, it will be apparent to those skilled in the art that modifications and variations can be made without departing from the spirit and scope of the invention as defined by the appended claims.