Abstract:
A plasma display having improved heat sink efficiency and reduced manufacturing cost includes a heat sink member made of an inexpensive graphite material having excellent thermal conductivity instead of a more expensive aluminum protective plate or a heat sink plate. The heat sink member serves as a heat sink of a Tape Carrier Package (TCP), an Intelligent Power Module (IPM), and other elements producing considerable amounts of heat.

Description:
CLAIM OF PRIORITY 
   This application makes reference to, incorporates the same herein, and claims all benefits accruing under 35 U.S.C. §119 from an application for PLASMA DISPLAY DEVICE earlier filed in the Korean Intellectual Property Office on the 29 Mar. 2006 and there duly assigned Serial No. 10-2006-0028656. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a plasma display, and more particularly, the present invention relates to a plasma display having improved heat sink efficiency and reduced manufacturing cost by including a heat sink for a Tape Carrier Package (TCP), or an Intelligent Power Module (IPM), etc., the heat sink being made of inexpensive graphite material having excellent thermal conductivity instead of an aluminum protective plate or a heat sink plate. 
   2. Description of the Related Art 
   A plasma display is a flat panel type display using a Plasma Display Panel (PDP). The PDP is produced by forming a plurality of electrodes on two substrates that are opposite to each other, arranging the substrates so as to be spaced apart from each other by a constant distance, and then sealing the substrates together after injecting discharge gases therebetween. 
   The plasma display includes the PDP and a plurality of drivers that are connected to each of the electrodes of the PDP. 
   Each pixel in the PDP is represented by a discharge in a pixel region. The discharge is generated by supplying a voltage to electrodes within a pixel space, so that a plasma or an excited state atom is produced. The power required for the discharge is partly dissipated as light, but mostly as heat. 
   The material of phosphors for forming the PDP have a disadvantage in that they are easily deteriorated and changed at high temperature, and their life shortened. By overheating, especially partial overheating in the PDP, a glass substrate can break due to stress caused by thermal expansion thereof. 
   The drivers, which are connected to the electrodes of the PDP, also dissipate a considerable amount of power in order to display a screen. The power dissipation results in thermal production. As a result, if the drivers are overheated, they can cause faulty operation. This faulty operation can cause deterioration in the quality of the screen. For example, a discharge can occur at a pixel which should not be discharged. Accordingly, it is very important to effectively radiate heat produced from the driver in the PDP. Since a considerable amount of heat is produced from a driving chip of the TCP, it is difficult to cool the driving chip if it does not contact a separate heat sink. 
   Usually, a chassis base, which is attached to a second surface of the PDP, is used to radiate heat from a heat generation part, such as the PDP and the drivers, to the outside. The chassis base is typically constituted by coupling a chassis-reinforcing member to a plate-type chassis base. The chassis-reinforcing member prevents deformation of the chassis base caused by external forces, and prevents the bending of the chassis base when the PDP is deformed by heat. As a result thereof, the deformation of the PDP may be also prevented. A driver for driving the PDP is arranged on a plurality of circuit substrates and mounted together with a power supply. The circuit substrate is usually spaced a constant distance apart from the chassis base through a boss, which is formed on the chassis base, in order for the ventilation of air. 
   The chassis base reinforces the mechanical strength by supporting the PDP and simultaneously receives heat from the PDP and the driver, which are in contact with the chassis base, and radiates the received heat to the outside. Additionally, the chassis base equally distributes the partly concentrated heat. For this reason, the chassis base is made of a metal, such as aluminum (Al), having excellent thermal conductivity. 
   However, the TCP and Chip On Film (COF) connect between the electrodes connected to the pixels of the PDP and drivers for driving the electrodes and have a built-in driving chip. Accordingly, a cooling problem of the driving chip occurs. Furthermore, an Intelligent Power Module (IPM) mounted on a driving board on a second surface of the chassis base includes a power transistor in one package, a protection circuit for protecting the power transistor, and a driving circuit for driving the power transistor. As a result thereof, the IPM produces a considerable amount of heat, and thus its cooling problem occurs. 
   Usually, a protection plate is mounted on an upper part of the TCP in order to protect the TCP and server as a heat sink of the TCP. The protection plate is usually made of aluminum. A protection plate made of aluminum has a disadvantage in that it is expensive and thus a manufacturing cost thereof is increased. Furthermore, a heat sink plate is mounted on an upper part of the IPM in order to serve as the heat sink of the IPM. The heat sink plate is also made of aluminum like the protection plate. Therefore, the protection plate made of aluminum has a disadvantage in that it is expensive and thus the manufacturing cost thereof is increased. 
   SUMMARY OF THE INVENTION 
   Accordingly, an object of the present invention is to provide a plasma display that has improved heat sink efficiency and reduced manufacturing cost by including a heat sink made of inexpensive graphite material having excellent thermal conductivity instead of an aluminum protective plate or a heat sink plate, for a TCP, or an IPM, etc., each of which produces a considerable amount of heat. 
   According to one aspect of the present invention, a plasma display is provided including: a Plasma Display Panel (PDP) to display images on a first surface thereof, the images being generated by a gas discharge; a chassis base arranged on a second surface of the PDP, the chassis base supporting the PDP; a driving circuit substrate arranged on the second surface of the chassis base; a Tape Carrier Package (TCP) having at least one element mounted on a connection cable electrically coupling the driving circuit substrate to the PDP; and a heat sink member arranged on the second surface of the TCP and contacting the at least one element, the heat sink member including a graphite layer, a holder to support the graphite layer, and a coating layer covering an area including a surface of the graphite layer opposite to the at least one element. 
   The chassis base preferably includes a chassis reinforcing member, the at least one element being supported by the chassis reinforcing member. The chassis base preferably includes a bent part on an end thereof, the at least one element being supported by the bent part. 
   The holder preferably surrounds part of the graphite layer. A vertical end surface of the holder preferably has a “           ” shape having a fixing groove on one surface thereof, the graphite layer being supported by being inserted into the fixing groove. The holder preferably includes a material selected from a group consisting of an iron alloy, aluminum alloy and stainless steel alloy.
   The coating layer preferably covers a surplus area except for an area where the graphite layer is surrounded by the holder. The coating layer preferably entirely covers a surface of the graphite layer. The coating layer preferably includes an elastic layer having a better elastic force than that of the graphite layer. 
   The elastic layer preferably includes a material selected from a group consisting of a paint coating layer, a thermal grease layer and a plastic coating layer. 
   The graphite layer is preferably supported by being affixed to the holder by an adhesive agent layer. 
   A thermally conductive medium is preferably interposed between the chassis reinforcing member and the at least one element. 
   According to another aspect of the present invention, a plasma display is provided including: a Plasma Display Panel (PDP) to display images on a first surface, the images being generated by a gas discharge; a chassis base arranged on a second surface of the PDP, the chassis base supporting the PDP; a driving circuit substrate arranged on the second surface of the chassis base and including an Intelligent Power Module (IPM); and a heat sink member arranged on the second surface of the IPM and contacting the IPM, the heat sink member including a graphite layer, a holder to support the graphite layer, and a coating layer covering an area of the graphite layer including a surface opposite to the IPM. 
   The holder preferably surrounds a part of the graphite layer. A vertical end surface of the holder preferably has a “           ” shape having a fixing groove on one surface, the graphite layer being supported by being inserting into the fixing groove. The holder preferably includes a material selected from a group consisting of iron alloy, aluminum alloy and stainless steel alloy.
   The coating layer preferably covers a surplus area except for an area where the graphite layer is surrounded by the holder. The coating layer preferably entirely covers the surface of the graphite layer. The coating layer preferably includes an elastic layer having a better elastic force than that of the graphite layer. 
   The elastic layer preferably includes a material selected from a group consisting of a paint coating layer, a thermal grease layer and a plastic coating layer. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A more complete appreciation of the present invention, and many of the attendant advantages thereof, will be readily apparent as the present invention becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings in which like reference symbols indicate the same or similar components, wherein: 
       FIG. 1  is a perspective view of a plasma display according to an exemplary embodiment of the present invention; 
       FIG. 2  is a vertical cross-sectional view taken along “A-A” line of  FIG. 1 ; 
       FIG. 3  is a vertical cross-sectional view of a corresponding part of  FIG. 2  of a plasma display according to another embodiment of the present invention; 
       FIG. 4  is a vertical cross-sectional view of a corresponding part of  FIG. 2  of a plasma display according to still another embodiment of the present invention; 
       FIG. 5  is a partial vertical cross-sectional view of a corresponding part of  FIG. 2  of a plasma display according to still another embodiment of the present invention; 
       FIG. 6   a  is a plane view of an arrangement of a driving circuit substrate of a plasma display according to still another embodiment of the present invention; 
       FIG. 6   b  is a perspective view of a scan driving board of  FIG. 6   a ; and 
       FIG. 6   c  is a cross-sectional view taken along “B-B” line of  FIG. 6   b.    
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Hereinafter, exemplary embodiments of the present invention are described in detail with reference to the accompanying drawing. The aspects and features of the present invention and methods for achieving the aspects and features will be apparent by referring to the embodiments described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed hereinafter, but can be implemented in diverse forms. The matters defined in the description, such as the detailed construction and elements, are merely specific details provided to assist those of ordinary skill in the art in a comprehensive understanding of the present invention, and the present invention is only defined within the scope of the appended claims. In the entire description of the present invention, the same drawing reference numerals are used for the same elements across various figures. 
     FIG. 1  is a perspective view of a plasma display according to an exemplary embodiment of the present invention, and  FIG. 2  is a vertical cross-sectional view taken along “A-A” line of  FIG. 1 . 
   Referring to  FIGS. 1 and 2 , the plasma display  100  according to the embodiment of the present invention includes a PDP  112  including a front panel  111  and a rear panel  113 , a chassis base  130  for supporting the PDP  112  at the second surface of the PDP  112 , and a plurality of driving circuit substrates  140 ,  142 ,  144 ,  146 ,  148  and  150 . A driving circuit is formed by mounting a plurality of electronic circuit boards on the driving circuit substrates  140 ,  142 ,  144 ,  146 ,  148  and  150 . Additionally, the plasma display includes a TCP  133  for electrically coupling apart of the driving circuit substrates  140 ,  142 ,  144 ,  146 ,  148  and  150  to an element  134  that is mounted on the TCP  133 . The plasma display  100  is in contact with the element  134  and includes a heat-sink  160  for rapidly radiating heat produced by the element  134 . 
   The PDP  112  includes a discharge cell (not shown) formed by a barrier rib between the front panel  111  and the rear panel  113  and a phosphor layer (not shown) formed within the discharge cell. The front panel  111  includes a plurality of display electrodes (not shown) having a straight line form and arranged horizontally parallel to each other. The rear panel  113  includes a plurality of address electrodes (not shown) having a straight line form and arranged vertically parallel to each other. The PDP  112  displays an image using a gas discharge that occurs inside a discharge cell due to a voltage supplied sequentially to the address electrodes and display electrodes on the first surface  111   a  of the front panel  111 . Hereinafter, the first surface  111   a  of the front panel  111  is the side of the front panel  111  displaying an image on PDP  112 , and the second surface is the side of the front panel  111  opposite to the first surface  111   a.    
   The chassis base  130  is attached to the second surface of the rear panel  113  to support the PDP  112 . The chassis base  130  is usually made of metal, preferably aluminum having excellent thermal conductivity and a relatively high mechanical strength. The chassis base  130  may be made of various materials, such as metal alloys, engineering plastics, etc. However, the present invention is not limited thereto. The chassis base  130  further includes a chassis reinforcing member  132  for preventing the bending and deformation of the chassis base  130  at the second surface thereof. The chassis reinforcing member  132  is formed on the second surface of the chassis base  130  so as to reinforce the strength of the chassis base  130 . The chassis reinforcing member  132  is manufactured separately from the chassis base  130  and attached to the chassis base  130  with screws, for example. The chassis reinforcing member  132  may be also formed together with the chassis base  130  as one body. Preferably, the chassis reinforcing member  132  is made of metal, more preferably aluminum material having excellent thermal conductivity and relatively high mechanical strength. The chassis reinforcing member  132  can be made of various materials, such as metal alloys. However, the present invention is not limited thereto. The chassis base  130  is fixed by supporting the PDP  112  by a double-sided tape  117  that is affixed to the second surface of the rear panel  113 . A thermal spread sheet (not shown) together with the double-sided tape  117  is interposed between the chassis base  130  and the rear panel  113 . The thermal spread sheet is formed of a carbon material having excellent thermal conductivity so as to transfer heat produced from the PDP  112  to the chassis base  130 . Furthermore, the chassis base  130  has an end part  130   a  touching a connect cable  134  in order to prevent damage to the connect cable  134 . 
   The plurality of driving circuit substrates  140 ,  142 ,  144 ,  146 ,  148  and  150  are arranged on the second surface of the chassis base  130 . The plurality of driving circuit substrates  140 ,  142 ,  144 ,  146 ,  148  and  150  are provided with a driving chip and electric/electronic devices, all of which are required to drive the PDP. 
   A lead-out electrode (not shown), which is connected to an address electrode and a sustain electrode, is arranged on a circumference of the PDP  112  that is attached in front of the chassis base  130 . The lead-out electrode is connected to the driving circuit substrate by the TCP  133 . 
   The TCP  133  is a package where an element  135  is mounted in the connect cable  134  made of a Flexible Printed Circuit (FPC). The connect cable  134  of the TCP  133  is arranged outside the PDP  112  and the chassis base  130 . The ends of the connect cable  134  are respectively electrically coupled to the driving circuit substrate and the PDP  112 . The element  135  is mounted on and electrically coupled to the connect cable  134 . The element  135  also includes elements, such as the driving chip for driving the PDP  112 . The element  135  is supported by and fixed to the chassis reinforcing member  132 . The element  135  may be supported by directly contacting the chassis reinforcing member  132 . The element  135  radiates a considerable amount of heat while the plasma display  100  is operating. The heat produced by the element  135  deteriorates the driving chip itself as well as the electronic circuit elements mounted on the driving circuit substrate. Therefore, there is a need to effectively radiate heat produced by the element  135 . A thermally conductive medium  136  may be formed between the chassis reinforcing member  132  and the element  135  in order to effectively radiate heat produced by the element  135 . Thermal grease, graphite, and the like, can be used as the thermally conductive medium  136 . The heat produced by the element  135  may be radiated by being transferred to the chassis reinforcing member  132 , and by being sequentially transferred to the thermally conductive medium  136  and the chassis reinforcing member  132 . The heat transferred to the chassis reinforcing member  132  may be radiated by being transferred back to the chassis base  130 . 
   The heat sink member  160  includes a graphite layer  162 , a holder  165  and a coating layer  168 . The heat sink member  160  is arranged to contact the entire area of the element  135  constituting the TCP  133 . The heat sink member  160  contacts the element  135  so as to effectively radiate heat produced by the element  135 . 
   The graphite layer  162  is formed as a thin lamella having a predetermined thickness, preferably at least 0.9 mm. However, the present invention is not limited thereto. The graphite layer  162  has a width and length covering an area in which the element of the TCP  133  is located, so that the element of the TCP  133  is wholly covered. Additionally, the graphite layer  162  has a wider area than that in contact with the element  135  in order to effectively radiate heat produced from the element  135 . 
   The graphite of the graphite layer  162  has a high thermal conductivity, i.e., approximately double the thermal conductivity of aluminum, so as to effectively radiate heat from the element  135 . The graphite layer  162  has a lamellar molecule structure, so that the thermal conductivity in a horizontal direction is higher than that in a vertical direction. Accordingly, even when the graphite layer  162  is formed to be thinner, the heat produced by the element  135  is dispersed at a very high speed and radiated to the outside, or transferred to the holder  165 . Additionally, the graphite layer  162  is less expensive than aluminum, and thus the manufacturing costs are decreased by using the graphite layer  162  instead of an aluminum protection plate. 
   The graphite layer  162  may be tightly in contact with the element  135  by an elastic force, and absorbs vibration produced by the element  135 . A heat sink characteristic of the graphite layer  162  is affected by a substantial contact area between the graphite layer  162  and a surface of the element  135 . The graphite layer  162  has the elastic force, and thus more effectively radiates heat from the element  135  when it is in contact with the element  135  by a predetermined pressure. Accordingly, the graphite layer  162  is formed to be in contact with the element  135  by providing the predetermined pressure via the holder  165 . 
   The holder  165  is formed to surround a part of the graphite layer  162 , and support the graphite layer  162  at the second surface of the graphite layer  162 , i.e., an opposite direction to first surface of the graphite layer  162  in contact with the element  135 . The holder  165  is in contact with a second surface of the graphite layer  162  to support the graphite layer  162 , and may be in contact with a side surface including the second surface to support the graphite layer  162 . Furthermore, the holder  165  may be formed to surround two side surfaces, an upper/lower surface and a rear side surface. In other words, the holder  165  may be formed to surround an entire side surface of the graphite layer  162 , except for a surface in contact with the element  135 . The holder  165  may be formed into a square box shape that is provided with a fixing groove  165   a  on one surface thereof. That is, a vertical end surface of the holder  165  may be formed into “           ” shape. The graphite layer  162  is fixed by being inserted into the fixing groove  165   a.  
   If the holder  165  is formed into the “           ” shape, it is possible to prevent the pressure on the element  135  being decreased due to an internal deformation caused by high heat for a long time. The holder  165  have higher strength than the material of the graphite layer  162 , is formed of a metal having a thermal conductivity, such as a steel alloy, aluminum alloy, stainless steel alloy, etc. Accordingly, the holder  165  supports the graphite layer  162  and has stiffness, so as to maintain the contact between the graphite layer  162  and the element  135 . The holder  165  is coupled to the chassis reinforcing member  132  or the chassis base  130  using fasteners, such as screws, etc. Additionally, the holder  165  may be formed by pressing or by casting. However, the present invention is not limited thereto.
   The coating layer  168  is formed to predetermined thickness on an outer surface of the graphite layer  162  in order to prevent dust from being produced by the graphite layer  162 . The graphite layer  162  is formed of graphite, thereby allowing fine dust particles to be produced during an installation process or when using the plasma display. This graphite dust has a high electrical conductivity according to characteristics of the graphite material, and thus can induce an electrical short when it is attached to the TCP  133  or other circuit board. The coating layer  168  is formed on a surplus surface except for a surface to be surrounded by the holder  165  within the outer surface of the graphite layer  162 , so as to be coated on the graphite layer  162  that is exposed to the outside. 
   The coating layer  168  may be formed of a material having a good elastic force as compared to the graphite layer  165 . The coating layer  168  directly contacts the element  135 , and thus can more effectively absorb the vibration produced by the element  135 , since it has better elastic force than the graphite layer  165 . When being formed as an elastic layer, the coating layer  168  may be a paint coating layer, a thermal grease layer or a plastic coating layer. However the present invention is not limited thereto. The coating layer  168  may be formed of various materials that have a higher elastic force than that of the graphite layer  162 . 
   A plasma display according to another embodiment of the present invention is explained in detail below. 
     FIG. 3  is a vertical cross-sectional view for a heat sink member used in a plasma display according to another embodiment of the present invention. 
   Hereinafter, the plasma display according to another embodiment of the present invention will be explained focusing on a part which is different from that of the embodiments of  FIGS. 1 and 2 . In other words, the plasma display according to another embodiment of the present invention is the same as that according to the embodiments of  FIGS. 1 and 2 , except for the heat sink member. Accordingly, an overall explanation for the plasma display according to another embodiment of the present invention has been omitted hereinafter, and the following explanation focusing on the heat sink member. Furthermore, the same reference numerals are used for the same or similar elements, and detailed descriptions of the same elements has been omitted. 
   The plasma display according to another embodiment of the present invention includes a PDP  112 , a chassis base  130 , a plurality of driving circuit substrates  140 ,  142 ,  144 ,  146 ,  148 , and  150 , and a heat sink member  260 . 
   Referring to  FIG. 3 , the heat sink member  260  includes a graphite layer  162 , a holder  165  and a coating layer  268 . The heat sink member  160  is in contact with the entire area of the element  135  constituting the TCP  133  so as to effectively radiate heat produced by the element  135 . 
   The coating layer  268  coats the entire outer surface of the graphite layer  162  and effectively prevents graphite dust from being produced by the graphite layer  162 . The coating layer  268  may have a higher elastic force than that of the graphite layer  162 . 
   Next, a plasma display according to still another embodiment of the present invention is explained in detail as follows. 
     FIG. 4  is a vertical cross-sectional view of a heat sink member used in the plasma display according to still another embodiment of the present invention. 
   Hereinafter, the plasma display according to still another embodiment of the present invention is explained focusing on a part which is different from that of the embodiments of  FIGS. 1 and 2 . In other words, the plasma display according to still another embodiment of the present invention is the same as that according to the embodiments of  FIGS. 1 and 2 , except for the heat sink member. Accordingly, an overall explanation for the plasma display according to still another embodiment of the present invention has been omitted hereinafter, and the explanation focusing on the heat sink member. Furthermore, the same reference numerals are used for the same or similar elements, and detailed descriptions of the same elements have been omitted. 
   The plasma display according to still another embodiment of the present invention includes a PDP  112 , a chassis base  130 , a plurality of driving circuit substrates  140 ,  142 ,  144 ,  146 ,  148 , and  150 , and a heat sink member  360 . 
   Referring to  FIG. 4 , the heat sink member  360  includes a graphite layer  162 , a holder  165 , a coating layer  168  and an adhesive agent layer  169 . The heat sink member  160  is in contact with the entire area of the element  135  constituting the TCP  133 , so as to effectively radiate heat produced by the element  135 . 
   The adhesive agent layer  169  is formed inside a fixing groove  165   a  of a holder  165 , preferably an area including a bottom area  165   b . Accordingly, the element  135  may be more securely attached to the holder  165  by the adhesive agent layer  169 . The adhesive agent layer  169  is a typically used adhesive agent. Preferably, the adhesive agent layer  169  may be formed as a thermally conductive adhesive agent having good thermal conductivity, and a thermal grease. If the adhesive agent layer  169  is a thermally conductive adhesive agent, it is possible to effectively radiate heat transferred to the graphite layer  162  toward the outside. 
   Next, a plasma display according to still another embodiment of the present invention is explained below. 
     FIG. 5  is a partial vertical cross-sectional view of the plasma display according to still another embodiment of the present invention. 
   Hereinafter, the plasma display according to another embodiment of the present invention is explained focusing on a part which is different from that of the embodiments of  FIGS. 1 and 2 . In other words, the plasma display according to still another embodiment of the present invention is the same as that according to the embodiments of  FIGS. 1 and 2 , except for a structure of the chassis base and a supporting location of the heat sink member. Accordingly, an overall explanation for the plasma display according to still another embodiment of the present invention has been omitted hereinafter, and the explanation focusing on the chassis base and the heat sink member. Furthermore, the same reference numerals are used for the same or similar elements, and detailed descriptions of the same elements have been omitted. 
   The plasma display according to still another embodiment of the present invention includes a PDP  112 , a chassis base  230 , a plurality of driving circuit substrates  140 ,  142 ,  144 ,  146 ,  148 , and  150 , and a heat sink member  160 . The heat sink member  160  may use the heat sink member  260  of  FIG. 3  or the heat sink member  360  of  FIG. 4 . 
   The chassis base  230  supports the PDP  112  at the second surface of the PDP  112 . An end part of the chassis base  230  is bent in a “           ” shape so as to form a bent part  232 . The bent part  232  supports the element  135  at the outer surface thereof.
   Referring to  FIG. 5 , the bent part  232  is formed by bending the end part of the chassis base  230  three times so as to enable the element  135  to be supported. However, the shape of the bent part to be formed at the end part of the chassis base  230  may be formed in various shapes capable of supporting the element  135 . The present invention is not limited to the bent part  232  of  FIG. 5 . The chassis base  230  can form the bent part  232  on the end part thereof without a separate chassis reinforcing member. The bent part  232  forms the end part  232   a  touching the connect cable  234 , so as to prevent the connect cable  234  from being damaged. The connect cable  234  is formed to be the same as the connect cable  134  of  FIG. 1 , except for the mounting location of the element  135 . Accordingly, an explanation thereof has been omitted. 
   A thermally conductive medium  136  is formed between the bent part  232  and the element  135 . The thermally conductive medium  136  may not be formed in some cases. In this case, the element  135  is supported by directly contacting the bent part  232 . 
   Next, a plasma display according to still another embodiment of the present invention is explained as follows. 
     FIG. 6   a  is a plane view of an arrangement of a driving circuit substrate of a plasma display according to still another embodiment of the present invention.  FIG. 6   b  is a perspective view of a scan driving board of  FIG. 6   a , and  FIG. 6   c  is a cross-sectional view taken along “B-B” line of  FIG. 6   b.    
   Hereinafter, the plasma display according to still another embodiment of  FIG. 6   b  is explained focusing on a part which is different from that of the embodiments of  FIGS. 1 and 2 . In other words, the plasma display according to still another embodiment of  FIG. 6   b  is the same as that according to the embodiments of  FIGS. 1 and 2 , except that the heat sink member  160  is formed on a second surface of the IPM. Accordingly, an overall explanation for the plasma display according to still another embodiment of the present invention has been omitted hereinafter, and an explanation focusing on the chassis base and the heat sink member. Furthermore, the same reference numerals are used for the same or similar elements, and detailed descriptions of the same elements have been omitted. 
   The plasma display according to still another embodiment of the present invention includes a PDP  112 , a chassis base  130 , a plurality of driving circuit substrates  540 ,  542 ,  544 ,  546 ,  548 , and  550 , and a heat sink member  160 . The heat sink member  160  can use the heat sink member  260  of  FIG. 3  or the heat sink member  360  of  FIG. 4 . 
   Referring to  FIGS. 6   a  to  6   c , the driving circuit substrates  540 ,  542 ,  544 ,  546 ,  548  and  550  include a Switching Mode Power Supply (SMPS)  540 , a logic board  542 , an address buffer board  544 , a sustain driving board  546 , a scan buffer board  548  and a scan driving board  550 , and are coupled to a second surface of the chassis base  130  through a boss (not shown) or the like. An arrangement of the driving circuit substrates  540 ,  542 ,  544 ,  546 ,  548  and  550  may be changed according to specification of the plasma display. A plurality of electronic circuit elements are mounted on the driving circuit substrates  540 ,  542 ,  544 ,  546 ,  548  and  550 , and the IPM  552  is mounted on a part of the driving circuit substrates  540 ,  542 ,  544 ,  546 ,  548  and  550 . For convenience of explanation, the IPM  552  formed on the scan driving board  550  will be explained below as an example. Accordingly, the following explanation can be applied to other driving circuit substrates on which the IPM  552  is mounted, except for the scan driving board  550 . 
   The SMPS  540  may be located above the logic board  542 , and is electrically coupled through the logic board  542 , the address buffer board  544 , the scan driving board  550  and the sustain driving board  546 , and a Flexible Printed Circuit Board (FPC) or a Flexible Flat Cable (FFC). The SMPS  540  supplies power to a driving circuit and the PDP  112 . The SMPS  540  is also equipped with an AC/DC converter that converts an Alternating Current (AC) current from an external source into a Direct Current (DC) current. 
   The address buffer board  544  is provided with an IPM, a timing controller, a plurality of signal input terminals, and a circuit portion for processing data. The address buffer board  544  may be formed on a lower part of the chassis base  330 , as shown in  FIG. 6   a . One address buffer board  544  may also formed on an upper part of the chassis base  330 , and two address buffer boards  544  may be respectively formed on the upper and lower parts one by one. However, the number of address buffer board  544  and the location thereof are not limited. 
   The scan buffer board  548  arranges data to be input to the scan electrode. 
   The plurality of electronic circuit elements including the IPM  552  are mounted on the scan driving board  550 , and the thermal sink member  160  is affixed to the second surface of the IPM  552 . For convenience of explanation, the electronic circuit elements except for the IPM  552  are not shown in  FIGS. 6   b  and  6   c . The scan driving board  550  is synchronized to a signal from the timing controller so as to generate a scan signal, and supplies the generated scan signal to a scan electrode. The scan driving board  550  may be electrically coupled through the SMPS  540 , the address buffer board  544 , the logic board  542  and the scan buffer board  548 , and the FPC or the FFC. The electrical coupling may be differently formed according to the circuit design. 
   At least one IPM  552  is mounted on a predetermined area of the scan driving board  550 . The IPM  552  is equipped with a power transistor, a protection circuit for protecting the power transistor and a driving circuit for driving the power transistor. Thus, since the IPM  552  produces a considerable amount of heat, it is very important to cool the IPM  552 . 
   The heat sink member  160  is formed to cover the IPM  552 . It is preferable for the heat sink member  160  to have a larger area than the IPM  552 . Although not shown in the drawings, the heat sink member  160  may be coupled to the chassis base  130  (referring to  FIGS. 1 and 2 ) using fasteners, such as screws, etc. 
   Next, an operation of the plasma display according to the present invention is explained as follows. For convenience of explanation, the embodiments of  FIGS. 1 and 2  are explained below as an example. 
   The plasma display  100  includes the PDP  112 , the chassis base  130 , the driving circuit substrates  140 ,  142 ,  144 ,  146 ,  148  and  150 , the TCP  133  and the thermal sink member  160 . 
   If the heat is produced by the element  135  of the TCP  133 , a part of the heat is transferred to the chassis reinforcing member  132  through the thermally conductive medium  136  touching the front of the element  135 . Some of the heat transferred to the chassis reinforcing member is radiated by itself, others is radiated by being transferred to the chassis base  130 . 
   The element  135  is supported by the thermal sink member  160  to maintain contact with the graphite layer  162 . Accordingly, the element  135  transfers some of the produced heat to the graphite layer  162  touching the second surface of the element  135 . The graphite layer  162  disperses the transferred heat in a horizontal direction within a short time interval so as to radiate most of the heat by itself, the remaining heat is transferred to the holder  165  touching the second surface thereof. The holder  165  radiates the transferred heat to the outside. 
   The heat sink member  160  forms a coating layer  168  between the graphite layer  162  and the element  135 , in order to prevent an electrical short on the circuit substrate caused by graphite particles produced by the graphite layer  162 . 
   If the coating layer  168  of the heat sink member  160  is formed as an elastic layer, the vibration produced by the element  135  can be absorbed. 
   As described above, the plasma display, according to the present invention, produces the following effect. 
   First, the plasma display uses a graphite layer having better heat conductivity than aluminum (Al) as the heat sink member, thereby allowing a considerable amount of heat produced by the TCP and/or IPM to be more rapidly radiated. 
   Second, the coating layer is formed on the outer surface of the graphite layer, thereby preventing electrical shorting of the circuit substrate due to graphite particles. 
   Third, the plasma display uses graphite as the heat sink member, the graphite being inexpensive as compared to aluminum, thereby allowing the manufacturing costs to be decreased. 
   The embodiments of the present invention have been described for illustrative purposes, and those skilled in the art will appreciate that various modifications, additions and substitutions are possible without departing from the scope of the present invention as defined by the appended claims.