Abstract:
A system comprising a first board for electrical communication with a second board, at least one electrical communication connector positioned on one side of said first board, and slots constructed in said first board, said slots adapted for allowing at least one electrical communication connector positioned on said second board to mate through said slots with said first board electrical communication connector.

Description:
BACKGROUND 
   In many situations two or more electronic circuit boards are interconnected together by mating connectors. In some situations, blades on one board mate with connectors on a second board. Each blade can carry one or more electrical circuits. These circuits can include data signals and/or power. Heat generated by electronic components on the electronic boards tends to increase as the density of the components increase. Often a limiting factor in circuit design is the amount of heat that can be removed from a given configuration. Typically, the air volume necessary for proper heat removal is proportional to the amount of heat generated. 
   It is sometimes desired to move circuit boards closer to each other to free up room for heat sinks and other heat management devices. However, when electronic boards are electrically connected, the blade connector that is positioned on one board physically limits how close the two boards can be positioned. This connector then determines the spacing between adjacent boards and limits the cooling options available to a system designer. 
   BRIEF SUMMARY 
   In one embodiment a system comprises a first board for electrical communication with a second board, at least one electrical communication connector positioned on one side of said first board, and slots constructed in said first board, said slots adapted for allowing at least one electrical communication connector positioned on said second board to mate through said slots with said first board electrical communication connector. 
   Another embodiment comprises a system for reducing the space between electronic boards when said electronic boards are electrically connected together using electronic connectors, the system comprising a first electronic board having mounted on a first side thereof at least one said electronic connector, a second electronic board having mounted theron at least one electronic connector adapted to mated with the first board electronic connector, and a slot constructed through the first electronic board to facilitate the mating of the first and second board electronic connectors when the second board is positioned in juxtaposition with a second side of the first electronic board. 
   Another embodiment comprises a system and method for electrically interconnecting at least two electrical circuits, such that first and second ones of the electrical circuits are positioned such that a first side of a first one of the electrical circuits is positioned parallel to and facing a first side of a second one of the electrical circuits, and at least a portion of electrical connectors positioned on the first side of the second electrical circuit is inserted though the first circuit to mate with electrical connectors positioned on a second side of the first electronic circuit. 
   Another embodiment comprising a system for increasing cooling capacity of at least two circuit boards interconnected electrically using electrical connectors, the system comprising means for positioning said at least two circuit boards in touching juxtaposition, the means comprising at least one said electrical connector positioned on a side of the first one of said circuit boards opposite the side of the touching juxtapostion, and at least one opening through the first one of the circuit boards, the opening facilitating the electrical interconnecting between the first and second circuit boards. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of one embodiment showing two circuit boards having mating connectors thereon; 
       FIG. 2  is a side view of the circuit boards shown in  FIG. 1  prior to mating; and 
       FIG. 3  is a side view of the circuit boards shown in  FIG. 1  in mating relationship; 
   

   DETAILED DESCRIPTION 
     FIG. 1  illustrates one embodiment  10  in which a first circuit board  11  has a number of connectors  15  positioned on the backside of the board. In the embodiment shown, connectors  15  are female connectors and the backside is the side away from the side in which a second board  12  is to be connected. In front of each connector  15 , a slot  14  is constructed through the board in such a manner that one or more connectors  13  (which in this case are a plurality of parallel spaced apart blade connectors on the face of electronic board  12 ,  FIG. 2 ) will fit through the slot for mating with connectors  15 . In the embodiment shown, board  11  contains one or more circuits  100 . The circuits could be, for example, processors. The blade connectors may extend perpendicular, i.e. at 90°, to the face of board  12 . 
   Electronic board  11  (which in the embodiment is a powerboard) sends power to board  12  through one or more blades  13  when board  12  is mated with board  11 . In addition to power, bidirectional control signals can be passed back and forth through one or more of blades  13 . Power board  11  is shown with stops  201  positioned in the corners to mate against the front plane of board  12 . These stops serve to maintain a fixed distance between the two boards when they are mated. 
   Slots  14  can be constructed in board  11  without regard to the number of connectors  15  that are positioned behind board  11 . If desired, each slot can be as wide as desired and thus could allow multiple connectors  13  to fit through each slot. Any number of connectors can be used depending upon the circuits to be mated therewith. The slots can, if desired, be used to guide and or hold blades  13  in position once board  12  is mated against board  11 . If desired, a locking mechanism (not shown), such as a latch, velcro, fastener, etc. can be utilized to hold boards  11  and  12  in mating relationship. Each blade  13  can have a plurality of power or signals on contacts  13   a – 13   n  thereof. Contacts  13   a – 13   n  can be on one or both sides of the blade. 
     FIG. 2  shows a side view of system  10  in which power board  11  has connector  15  positioned behind slot  14 . Electronic board  12  having blade  13  mounted thereon, is shown just prior to mating with power board  11 . Blade  13  is about to enter slot  14  for subsequent mating with connector  15 . 
     FIG. 3  shows boards  11  and  12  fully mated with blade connector  13  passed through slot  14  and fully inserted into connector  15 . The distance between boards  11  and  12  is shown in the embodiment of  FIG. 3  as 0.020 and is controlled by stops  201 . This distance can be any desired distance depending upon circuitry and the desired board spacing. 
   Shown between boards  11  and  12  is heat sink  33 . Heat sink  33  can be positioned on board  12  and utilized by both boards  12  and  11  if desired. Also a heat sink, such as heat sink  32 , can be positioned as shown with respect to electronic device  31  on the back sides of boards  11  or  12 . Other circuitry can also be positioned, if desired on the back side of power board  11 , or between boards  11  and  12  or on the back surface of board  12   
   Since connector  15  is on the back surface of board  11 , boards  11  and  12  can be mated in a smaller area than before. This leaves the dimension Y available for additional circuitry or cooling capability. Also, connector  15  can be larger than if it were positioned between boards  11  and  12  and therefore may be made more robust. This robustness reduces manufacturing difficulties and system errors and also allows for increased signaling and power transfer ability between boards  11  and  12 . 
   By way of example, the relative spacing between the embodiment described herein and at least one prior system, is as follows: 
   
     
       
             
             
             
           
             
             
             
           
         
             
                 
                 
             
             
                 
               Prior System 
               Embodiment of FIG. 3 
             
             
                 
                 
             
           
           
             
                 
             
           
        
         
             
               Total Spacing (X) 
               0.44 in. 
               0.51 in. 
             
             
               Spacing between connected boards 
               0.28 in. 
               0.02 in. 
             
             
               Connector Size 
               0.28 in. 
               0.33 in. 
             
             
               Additional available space (Y) 
                 
               0.26 in. 
             
             
                 
             
           
        
       
     
   
   Thus, by increasing the overall size by 0.07 in. (by adding 0.05 in. to the connector dimension and allowing 0.02 in. as fixed spacing) there is gained an additional 0.26 in. for cooling and/or additional equipment. Of course, if connector  15  remains at the size of the old connector (0.28 in), then 0.31 in. are available for cooling on other needs. 
   Note that while the slots are shown in a vertical orientation, they could also lie in the horizontal plane or any other orientation, provided they match the orientation of the respective board connectors.