Patent Publication Number: US-8986048-B2

Title: Integrated feedthrough module

Description:
CROSS-REFERENCE TO OTHER APPLICATIONS 
     This is a divisional of U.S. patent application Ser. No. 12/437,465, filed on May 7, 2009. 
    
    
     BACKGROUND OF THE INVENTION 
     This invention relates to test equipment for testing devices having electrical circuits including integrated circuits. 
     When fabrication of electronic devices, such as computer processors and memories, has been completed, the electronic devices are subjected to burn-in and electrical testing in order to identify and eliminate defective devices before shipment. The term “burn-in” relates to operation of an integrated circuit at a predetermined temperature or temperature profile, typically an elevated temperature in an oven. Certain operating electrical bias levels and/or signals are supplied to the electronic devices while they are at the elevated temperature. The use of the elevated temperature, electrical bias and functional input signals accelerates stress to which the devices are subjected during burn-in, so that marginal devices that would otherwise fail shortly after being placed in service fail during burn-in, and are, therefore not shipped. 
     SUMMARY OF THE INVENTION 
     The invention relates to an apparatus for testing an integrated circuit of an electronic device, including an apparatus frame, a power source mounted to the apparatus frame, a power electrical path connecting the power source to power contacts on the electronic device, a signal source; and a plurality of signal electrical paths, each connecting the signal source to a respective signal contact on the electronic device. 
     The apparatus may further include a blower mounted to the apparatus frame, the blower blowing air through at least part of the apparatus frame. 
     In the apparatus, the apparatus frame may include a test electronics frame and a blower frame, the power source and the signal source being located in the test electronics frame and jointly forming part of a test electronics module, and the blower being mounted the blower frame and jointly being part of a blower module, the test electronics module and the blower module being removably mounted to one another. 
     In the apparatus, the apparatus frame may further include a driver electronics part and an oven part, the blower being an oven blower and the blower frame being an oven blower frame housing the electronics device, the oven blower being mounted to the oven blower frame and jointly being part of an oven blower module, the oven blower blowing air through the oven blower part. 
     In the apparatus, the apparatus frame may further include a driver blower frame, further including a driver electronics blower mounted to the driver electronics blower frame and jointly being part of a driver electronics blower module, the driver blower blowing air through the driver electronics part, the test electronics module and the driver electronics module being removably mounted to one another. 
     The apparatus may further include a blower bearing mount secured to the apparatus frame, wherein the blower includes a blower bearing held by the lower bearing mount, a blower input shaft held by the blower bearing and being rotatable relative to the blower bearing mount; and a fan mounted on the shaft to rotate together with the shaft. 
     The apparatus may further include a blower motor bearing mount secured to the apparatus frame, a blower motor including, a blower motor body secured to the apparatus frame, a blower motor stator held by the blower motor body, a blower motor rotor rotatably held by the blower motor body, a blower motor output shaft connected to the blower motor rotor for rotation therewith, the blower input shaft being driven by the blower motor output shaft. 
     The apparatus may further include a blower motor pulley connected to the blower motor output shaft, a blower pulley connected to the blower input shaft; and a drive belt running over the motor pulley and the blower pulley. 
     The apparatus may further include spacer component between the apparatus frame and a selected one of the mounts, the spacer component being removable to permit removal of the drive belt. 
     In the apparatus, the selected mount may be the blower bearing mount, the blower pulley being located between the blower bearing and the fan. 
     The apparatus may further include first and second sets of opposing rails, first and second sides of a respective device holder being releasably held by opposing rails of the first and second sets of rails. 
     The apparatus may further include a device holder substrate, a plurality of device holder terminals on the device holder substrate, each for contacting a respective contact on a respective electronic device, a plurality of device holder signal contacts secured to the device holder substrate, each device holder signal contact having a surface for releasably mating with a respective surface of a respective signal connector terminal, a plurality of device holder signal conductors connecting the device holder signal contacts to device holder terminals connected to signal contacts on the electronic devices, a power contact secured to the device holder substrate, the power connector having a contact surface for releasably mating with a respective surface of a respective power connector terminal; and at least one device holder power conductor connecting the device holder board power contact to a power contacts on one of the electronic devices. 
     The apparatus my further include an interior frame that is removably located within the apparatus frame, the interior frame having first and second opposing vertical sides and the first and second sets of opposing rails being located on first and second opposing side walls, respectively, of the subframe. 
     In the apparatus, the interior frame may have third and fourth opposing side walls, further including third and fourth sets of opposing rails being located on the third and fourth opposing vertical sides of the subframe, first and second sides of a first electronics board being releasably held by opposing rails of the third and fourth sets of rails and the first electronics board electrically connecting to the device holder subassembly. 
     In the apparatus, the interior frame may have a fifth vertical side opposing the fourth side wall, further including fifth and sixth sets of opposing rails being located on the fourth and fifth opposing vertical sides of the subframe, first and second sides of a second electronics board being releasably held by opposing rails of the fifth and sixth sets of rails and the second electronics board electrically connecting to the device holder subassembly. 
     The apparatus may further include a first module including a first connector including a connector body, a first set of connector terminals on the connector body for connecting to respective ones of a first set of device holder contacts of a device holder, a first set of connector contacts on the connector body for connecting to respective ones of a first set of board terminals of a board; and a first set of connector conductors carried by the connector body and connecting the first set of connector terminals to the first set of connector contacts. 
     The apparatus may further include a second set of connector terminals on the connector body, the second set of connector terminals being spaced from the first set of connector terminals in a direction that the device holder engages with the connector body. 
     In the apparatus, the device holder may include first and second sets of device holder contacts spaced from one another on a device holder substrate and contacting the first and second sets of connector terminals respectively. 
     In the apparatus, the device holder may further include a second set of connector contacts on the connector body, the second set of connector contacts being spaced from the first set of connector contacts in a direction that the board engages with the connector body. 
     In the apparatus, the first set of connector conductors may connect the first connector terminals with the first connector contacts, further including a second set of connector conductors connecting the second set of connector contacts with the second set of connector terminals. 
     The apparatus may further include a first set of terminal spring portions, each terminal spring portion of the first set of terminal spring portions urging a respective connector terminal of the first set of connector terminals against a respective board contact of the first set of board contacts, a second set of terminal spring portions, each terminal spring portion of the second set of terminal spring portions urging a respective connector terminal of the second set of connector terminals against a respective board contact of the second set of board contacts, a first set of contact spring portions, each contact spring portion of the first set of contact spring portions urging a respective connector contact of the first set of connector contacts against a respective board contact of the first set of board contacts; and a second set of terminal spring portions, each terminal spring portion of the second set of terminal spring portions urging a respective connector terminal of the second set of connector terminals against a respective board terminal of the second set of board terminals. 
     In the apparatus, the board may include first and second sets of board terminals spaced from one another on a board substrate and contacting the first and second sets of connector contacts respectively. 
     The apparatus may further include a first insulation piece secured against the connector body. 
     In the apparatus, the first integrated module may include a feedthrough board including, a feedthrough board substrate, and a first feedthrough board electric conductor carried by the feedthrough board substrate and connected to the first connector contact, the first insulation piece being located against the feedthrough board substrate. 
     In the apparatus, the first integrated module may further include a second insulation piece secured to the connector body on an opposite side to the first insulation piece. 
     In the apparatus, the first integrated module may further include a feedthrough board including a feedthrough board substrate, and a first feedthrough board electric conductor carried by the feedthrough board substrate and connected to the first connector contact, the first and second insulation pieces being located against and on opposite sides of the feedthrough board substrate. 
     The apparatus may further include a plurality of said integrated modules jointly forming an insulated wall. 
     The apparatus may further include a first driver board including a first driver board substrate, a first driver board electric conductor carried by the driver board substrate, and a first driver board terminal connected to the first driver board electric conductor, a first one of the connector contacts being electrically connected to the first driver board terminal. 
     In the apparatus, the first connector contact may be offset from a line at right angles to a side of the driver board substrate at the driver board terminal. 
     The apparatus may further include a backplane board including a backplane substrate, and a first backplane electric conductor carried by the backplane substrate and extending from a first driver board terminal plane through the first diver board terminal to a first connector contact plane through the first connector contact, the first driver board terminal plane and the first connector contact plane being spaced and parallel to one another, the first backplane electric conductor connecting the first driver board terminal and the first connector contacts electrically to one another. 
     In the apparatus, the first connector contact plane may be parallel to and offset from a plane of the driver board substrate. 
     The apparatus may further include a feedthrough board including a feedthrough board substrate, and a first feedthrough board electric conductor carried by the feedthrough board substrate and extending in a direction other than at right angles to a plane of the first driver board substrate, the first feedthrough board electric conductor connecting the first driver board terminal and the first connector contacts electrically to one another. 
     In the apparatus, the first feedthrough board electric conductor may extend in a direction other than at right angles to a plane of the first driver board substrate. 
     In the apparatus, the first connector contact may be offset from the first driver board terminal in a direction parallel to a plane of the driver board substrate. 
     The apparatus may further include a second driver board including a second driver board substrate, a second driver board electric conductor carried by the driver board substrate; and a second driver board terminal connected to the second driver board electric conductor, the second driver board terminal being connected to the first driver board terminal. 
     The apparatus may further include a feedthrough board including a feedthrough board substrate, and a feedthrough board electric conductor carried by the feedthrough board substrate and connecting the first and second driver board terminals to one another. 
     The apparatus may further include a first backplane board including a first backplane substrate, and a first backplane electric conductor carried by the first backplane substrate and connecting the first driver board terminal and the feedthrough board electric conductor electrically to one another; and a second backplane board including a second backplane substrate separate from the first backplane substrate, and a second backplane electric conductor carried by the second backplane substrate and connecting the second driver board terminal and the feedthrough board electric conductor electrically to one another. 
     In the apparatus, the first and second backplane substrates may extend in a plane that is at right angles to planes of the first and second driver board substrates and a plane of the feedthrough substrate. 
     In the apparatus, the first driver board may be a power board and the second driver board may be a signal board. 
     In the apparatus, the apparatus frame may define a door opening, further including a first translation system mounted to the apparatus frame, a first hinge base mounted to the first translation system, the first translation system allowing for translation of the first hinge base relative to the apparatus frame between a storage position and an operational position a door panel mounted to the first hinge base, the door panel being pivotally movable relative to the first hinge base when the first hinge base is in the operational position between a storage orientation wherein the door opening is open and an closed orientation wherein the door panel closes the door opening, and a latch mechanism that releasably maintains the door in the closed position. 
     In the apparatus, the apparatus frame may define a door opening, further including a second translation system mounted to the apparatus frame, a second hinge base mounted to the second translation system, the second translation system allowing for translation of the second hinge base relative to the apparatus frame between the storage position and the operational position, the door panel being mounted to the second hinge base, the door panel being pivotally movable relative to the second hinge base when the hinge base is in the operational position between the storage orientation wherein the door opening is open and the closed orientation wherein the door panel closes the door opening. 
     In the apparatus, the first and second translation systems may be upper and lower translation systems and the door pivots about an axis that is substantially vertical. 
     The apparatus may further include a connecting structure that secures the first and second hinge bases to one another. 
     In the apparatus, the first translation system may include a first track that is mounted to the apparatus frame and a first wheel that is rotatably mounted to the first pivot base, the first wheel having an outer surface that rides on the rail. 
     The invention further provides a device holder subassembly, including a device holder substrate, a plurality of device holder terminals on the device holder substrate, each for contacting a respective contact on a respective electronic device, a plurality of device holder signal contacts secured to the device holder substrate, each device holder signal contact having a surface for releasably mating with a respective surface of a respective signal connector terminal, a plurality of device holder signal conductors connecting the device holder signal contacts to device holder terminals connected to signal contacts on the electronic devices, a power contact secured to the device holder substrate, the power connector having a contact surface for releasably mating with a respective surface of a respective power connector terminal, and at least one device holder power conductor connecting the device holder board power contact to a power contacts on one of the electronic devices. 
     In the device holder assembly, the connector terminals may include first and second sets of connector terminals, the second set of connector terminals being spaced from the first set of connector terminals in a direction that the device holder engages with the connector body. 
     In the device holder assembly, the device holder may include first and second sets of device holder contacts spaced from one another on a device holder substrate and contacting the first and second sets of connector terminals respectively. 
     The invention further provides a method of testing an integrated circuit of an electronic device, including holding the device against a surface of a first device holder so that signal and power terminals of the holder are in contact with signal and power contacts on the electronic device, providing signals through the signal terminals and contacts to the integrated circuit, providing power through the power terminals and contacts to the integrated circuit. 
     The method may further include blowing air with a blower through at least part of the apparatus frame. 
     In the method, the apparatus frame may include a test electronics frame and a blower frame, the power source and the signal source being located in the test electronics frame and forming part of a test electronics module, and the blower being mounted the blower frame and being part of a blower module, further including removably mounting the test electronics module and the blower module to one another. 
     In the method, the apparatus frame may include a driver electronics part and an oven part, the blower being an oven blower and the blower frame being an oven blower frame housing the electronics device, the oven blower being mounted to the oven blower frame and jointly being part of an oven blower module, the oven blower blowing air through the oven blower part. 
     In the method, the apparatus frame may include a driver blower frame, a driver electronics blower mounted to the driver electronics blower frame and jointly being part of an driver electronics blower module, further including removably mounting the test electronics module and the driver electronics module removably to one another for the driver blower to blow air through the driver electronics part. 
     The method may further include releasably holding first and second sides of a respective device holder by a opposing rails of first and second sets of rails. 
     The method may further include removing an interior frame out of the apparatus frame, the first and second sets of opposing rails being located on first and second opposing vertical sides of the subframe. 
     In the method, the third and fourth sets of opposing rails may be located on third and fourth opposing vertical sides of the subframe, first and second sides of the first electronics board being releasably held by opposing rails of the third and fourth sets of rails and the first electronics board electrically connecting to the device holder subassembly. 
     In the method, the fifth and sixth sets of opposing rails may be located on the fourth and a fifth opposing vertical sides of the subframe, first and second sides of the second electronics board being releasably held by opposing rails of the fifth and sixth sets of rails and the second electronics board electrically connecting to the device holder subassembly. 
     The invention further provides a module including a first connector including, a connector body, a first set of connector terminals on the connector body for connecting to respective ones of a first set of device holder contacts of a device holder, a first set of connector contacts on the connector body for connecting to respective ones of a first set of board terminals of a board, and a first set of connector conductors carried by the connector body and connecting the first set of connector terminals to the first set of connector contacts. 
     The module may further include a second set of connector terminals on the connector body, the second set of connector terminals being spaced from the first set of connector terminals in a direction that the device holder engages with the connector body. 
     In the module, the device holder may include first and second sets of device holder contacts spaced from one another on a device holder substrate and contacting the first and second sets of connector terminals respectively. 
     The module may further include a second set of connector contacts on the connector body, the second set of connector contacts being spaced from the first set of connector contacts in a direction that the board engages with the connector body. 
     In the module, the first set of connector conductors may connect the first connector terminals with the first connector contacts, further including a second set of connector conductors connecting the second set of connector contacts with the second set of connector terminals. 
     The module may further include a first set of terminal spring portions, each terminal spring portion of the first set of terminal spring portions urging a respective connector terminal of the first set of connector terminals against a respective board contact of the first set of board contacts, a second set of terminal spring portions, each terminal spring portion of the second set of terminal spring portions urging a respective connector terminal of the second set of connector terminals against a respective board contact of the second set of board contacts, a first set of contact spring portions, each contact spring portion of the first set of contact spring portions urging a respective connector contact of the first set of connector contacts against a respective board contact of the first set of board contacts; and a second set of terminal spring portions, each terminal spring portion of the second set of terminal spring portions urging a respective connector terminal of the second set of connector terminals against a respective board terminal of the second set of board terminals. 
     In the module, the board may include first and second sets of board terminals spaced from one another on a board substrate and contacting the first and second sets of connector contacts respectively. 
     The module may further include a first insulation piece secured against the connector body. 
     In the module, the first integrated module may further include a feedthrough board including a feedthrough board substrate, and a first feedthrough board electric conductor carried by the feedthrough board substrate and connected to the first connector contact, the first insulation piece being located against the feedthrough board substrate. 
     In the module, the first integrated module may further include a second insulation piece secured to the connector body on an opposite side to the first insulation piece. 
     In the module, the first integrated module may further include a feedthrough board including a feedthrough board substrate, and a first feedthrough board electric conductor carried by the feedthrough board substrate and connected to the first connector contact, the first and second insulation pieces being located against and on opposite sides of the feedthrough board substrate. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention is further described by way of example with reference to the accompanying drawings, wherein: 
         FIG. 1  is perspective view of an apparatus for testing integrated circuits of electronic devices, according to an embodiment of the invention; 
         FIG. 2  is perspective view of a door system forming part of the apparatus; 
         FIG. 3  is a view similar to  FIG. 1  after a door panel is rotated from a closed orientation to an open orientation; 
         FIG. 4  is a view similar to  FIG. 3  after the door panel and upper and lower hinge bases are moved from an operational position into a storage position; 
         FIG. 5  is perspective view of an interior frame that is located within a test electronics frame of the apparatus of  FIG. 4 ; 
         FIG. 6  is a perspective view of the interior frame from an opposing side than in  FIG. 5 ; 
         FIG. 7  is a cross-sectional end view through an oven portion of the test electronics module and through an oven blower module of the apparatus; 
         FIG. 8  is a cross-sectional end-view from an opposing side than in  FIG. 7  through a driver electronics portion of the test electronics module and through a driver electronics blower module; 
         FIG. 9  is a side view illustrating components of the oven blower module; 
         FIG. 10  illustrates an interconnection scheme of an electric tester forming part of the test electronics module; 
         FIG. 11  is a perspective view of the tester of  FIG. 10 ; 
         FIG. 12  is cross-sectional side view of a connector module forming part of the tester in  FIG. 11 ; 
         FIG. 13  is a perspective view illustrating how the connector module of  FIG. 12  is retained on the apparatus frame; 
         FIG. 14  is a cross-sectional side view illustrating a connector forming part of the connector module of  FIG. 12 , a feedthrough board and a burn-in board; 
         FIG. 15  is a perspective view of the connector of  FIG. 14 ; and 
         FIG. 16  is a top plan view of the burn-in board shown in  FIG. 14 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  of the accompanying drawings illustrates an apparatus  10  for testing integrated circuits of electronic devices such as unsingulated dies of a wafer or dies within separate integrated circuit packages. The apparatus  10  includes a test electronics module  12 , an oven blower module  14 , and a driver electronics blower module  16 . The modules  12 ,  14  and  16  are initially separate from one another. It is easier to transport the apparatus  10  when the modules  12 ,  14  and  16  are separate from one another and the modules  12 ,  14  and  16  are also sized so that they can fit through existing doorways of fabrication facilities. 
     The oven blower module  14  and the driver electronics blower module  16  are located side-by-side on top of the test electronics module  12 . Following transportation of the modules  12 ,  14  and  16 , the apparatus  10  is assembled as shown in  FIG. 1 . The test electronics module  12  has a test electronics frame  18 , the oven blower module  14  has an oven blower frame  20 , and the driver electronics blower module  16  has a driver electronics frame  22 . The oven blower frame  20  is then bolted to the test electronics frame  18  and the driver electronics frame  22  is bolted to the test electronics frame  18 . The test electronics frame  18 , oven blower frame  20 , and driver electronics frame  22  then jointly form an apparatus frame  24  with the test electronics frame  18 , oven blower frame  20 , and driver electronics frame  22  secured to one another. The oven blower module  14  and the driver electronics blower module  16  can still be removed from the test electronics module  12  by removing the bolts that secure the oven blower frame  20  and the driver electronics frame  22  to the test electronics frame  18 . It may for example be required to replace the oven blower module  14  with another oven blower module for another purpose. The oven blower module  14  may for example provide air cooling and may have to be replaced by an oven blower module having a water cooling capability. 
     As further illustrated in  FIG. 1 , the apparatus  10  includes a door system  26 , including upper and lower translation systems  28  and  30 , upper and lower hinge bases  32  and  34 , a connecting structure  36 , a door panel  38  and a latch mechanism  40 . 
     As shown in  FIG. 2 , the upper translation system  28  includes an upper horizontal track  42  and an upper set of wheels  44 . The track  42  is secured to the test electronics frame  18 . Each one of the wheels  44  is rotatably secured to the upper hinge base  32 . Each one of the wheels  44  has an outer surface that rides on the track  42 . The track  42  and the wheels  44  mount the upper hinge base  32  to the test electronics frame  18 . 
     Referring again to  FIG. 1 , the lower translation system  30  has a similar track-and-roller arrangement as the upper translation system  28 . The lower translation system  30  thus mounts the lower hinge base  34  to the test electronics frame  18 . The connecting structure  36  is located between the upper and lower hinge bases  32  and  34  and secures the upper and lower hinge bases  32  and  34  to one another so that they move in unison. 
     The upper and lower hinge bases  32  and  34  are shown in an operational position in  FIG. 1 , wherein they are located to the right on the upper and lower translation systems  28  and  30 . The door panel  38  is pivotally mounted to the upper and lower hinge bases  32  and  34  for pivotal movement about a substantially vertical axis. When the upper and lower hinge bases  32  and  34  are in the operational position as shown in  FIG. 1 , the door panel  38  can be pivoted into a closed orientation as shown in  FIG. 1 , wherein the door panel  38  closes a door opening defined in the test electronics frame  18 . The latch mechanism  40  is used to maintain the door panel  38  in the closed position. 
     As shown in  FIG. 3 , the latch mechanism  40  can be operated to release the door panel  38  so that it is not maintained in the closed position, whereafter the door panel  38  can be pivoted relative to the upper and lower hinge bases  32  and  34  while the upper and lower hinge bases  32  and  34  are in the operational position. The door panel  38  is pivoted from the closed orientation shown in  FIG. 1  to an open orientation shown in  FIG. 3  wherein a door opening  46  in the test electronics frame  18  is open. 
     Referring now to  FIGS. 3 and 4  in combination, the door panel  38 , after moving into the open orientation in  FIG. 3  and with the upper and lower hinge bases  32  and  34  in the operational position, can be moved to a storage position shown in  FIG. 4 , wherein the door panel  38  is located adjacent the test electronics frame  18 . The upper and lower hinge bases  32  and  34 , the connecting structure  36  and the door panel  38  move in unison into the storage position shown in  FIG. 4 . 
     In the storage position shown in  FIG. 4 , a passageway in front of the door opening  46  is not blocked by the door panel  38 . There is thus no need to close the door panel  38  in order to allow for movement through the passage. 
     In order to again close the door opening  46 , the door panel  38  together with the upper and lower hinge bases  32  and  34  and the connecting structure  36  are moved from the storage position shown in  FIG. 4  to the position in  FIG. 3  wherein the upper and lower hinge bases  32  and  34  are in the operational position and the door panel  38  is in the open orientation. The door panel  38  is then moved from the open orientation shown in  FIG. 3  to the closed orientation shown in  FIG. 1 . The latch mechanism  40  is operated to maintain the door panel  38  in the closed orientation. 
       FIGS. 5 and 6  illustrate an interior frame  50  and first, second, third, fourth, fifth and sixth sets of rails  52 A,  52 B,  52 C,  52 D,  52 E and  52 F, respectively, located on the interior frame  50 . The interior frame  50  is configured with additional electronics boards (not shown) that are located on the rails  52 C,  52 D,  52 E and  52 F, whereafter the interior frame  50  is located with the electronics boards and connectors mounted to the electronics boards through a rear door opening (not shown) in  FIG. 1  into the test electronics frame  18 . Electronic devices are held by a device-holder subassembly such as a burn-in board (not shown) and the burn-in board is located on the rails  52 A and  52 B and connected to the electronics boards located on the rails  52 C,  52 D,  52 E and  52 F. 
     The interior frame  50  has first, second, third, fourth, and fifth vertical sides  54 A,  54 B,  54 C,  54 D and  54 E. The vertical sides  54 A and  54 B oppose one another and the rails  52 A and  52 B are located on the vertical sides  54 A and  54 B, respectively. Each one of the rails  52 A thus opposes a respective one of the rails  52 B. The vertical sides  54 C and  54 D oppose one another and the rails  52 C and  52 D are located on the vertical sides  54 C and  54 D, respectively. The vertical sides  54 D and  54 E oppose one another and the rails  52 E and  52 F are located on the vertical sides  54 D and  54 E, respectively. The rails  52 C and  52 D oppose one another. The rails  52 E and  52 F oppose one another. 
     The interior frame  50  also has horizontal oven panels  56  that connect the vertical sides  54 A and  54 B to one another to form a subassembly and test electronics panels  58  that connect the vertical sides  54 C,  54 D and  54 E to one another to form a subassembly. The subassembly formed by the oven panels  56  and the vertical sides  54 A and  54 B is secured to the subassembly formed by the test electronics panels  58  and the vertical sides  54 C,  54 D and  54 E to complete the construction of the interior frame  50 . The interior frame  50  is thus a free standing unit before it is inserted into the test electronics frame  18  of  FIG. 4  and before it is loaded with electronics boards. The interior frame  50  can also be removed out of the test electronics frame  18  for purposes of reconfiguring the system. 
     The vertical sides  54 A,  54 B,  54 C,  54 D, and  54 E are made out of vertical strips  60  with spaces between the vertical strips  60 . The spaces between the vertical strips  60  provide openings so that air can flow horizontally through the vertical sides  54 A,  54 B,  54 C,  54 D, and  54 E into and out of the interior frame  50 . 
       FIG. 7  illustrates further components of the apparatus  10  including an oven blower  62  and an air channeling piece or damper  64  forming part of the oven blower module  14  and inlet and outlet plenums  66  and  68  forming part of the test electronics module  12 . 
     The oven blower  62  has first and second blower bearings  70  and  72 , a blower input shaft  74 , and an centrifugal fan  76 . The centrifugal fan  76  is mounted to the shaft  74 . The shaft  74  is rotatably mounted on the oven blower frame  20  by the first and second bearings  70  and  72 . 
     The damper  64  is mounted to the oven blower frame  20 . Air can pass over a surface of the air channeling piece  64  into an inlet of the centrifugal fan  76 . 
     The plenums  66  and  68  are mounted to the test electronics frame  18  on opposing sides of the interior frame  50  (see  FIG. 5 ) such that the plenum  66  is located next to the vertical side  54 A and the plenum  68  is located next to the vertical side  54 B. The plenum  66  forming part of the test electronics module  12  receives air from an outlet of the centrifugal fan  76  forming part of the oven blower module  14 . The plenum  68  forming part of the test electronics module  12  delivers air over the surface of the air channeling piece  64  forming part of the oven blower module  14 . 
     In use, burn-in boards are positioned between the vertical sides  54 A and  54 B. When power is provided to devices held by the burn-in boards, the devices and the burn-in boards generate heat. Heat is also provided, if needed, by a heater (not shown). The centrifugal fan  76  and the shaft  74  rotate on the first and second bearings  70  and  72  relative to the oven blower frame  20 . The centrifugal fan  76  receives air from the plenum  68  over the surface of the damper  64  and provides air to the plenum  66 . Parallel streams of air pass from the plenum  66  through the vertical side  54 A over the burn-in boards to the plenum  68 . Air continues to circulate through the test electronics module  12  and the oven blower module  14  so that air within an oven portion of the test electronics module  12  is at substantially the same temperature as air within the oven blower module  14 . The air continues to heat up as the burn-in boards, devices and heater generate more heat. When the temperature within the test electronics module  12  reaches a predetermined temperature, the damper  64 , forming part of the oven blower module  14  is opened to atmosphere and the heater is turned off. Air at close to atmospheric temperature is then drawn into the centrifugal fan  76  and heated air from the plenum  68  is vented to atmosphere. Excess heat is thereby removed from the apparatus  10 . The heater and damper work together to control the temperature of the air in the chamber. 
       FIG. 8  shows further components of the apparatus  10  including a driver electronics blower  80  forming part of the driver electronics blower module  16 , and inlet and outlet plenums  82  and  84  forming part of a driver electronics part of the test electronics module  12 . Electronics boards are positioned between the vertical sides  54 C and  54 D and more electronics boards are positioned between the vertical sides  54 D and  54 E. 
     In use, the electronics boards positioned between the vertical sides  54 C and  54 D and between the vertical sides  54 D and  54 E generate heat. The driver electronics blower  80  receives air from outside the apparatus  10  at atmospheric temperature and provides the air to the plenum  82 . Parallel streams of air flow from the plenum  82  to the plenum  84 . Each stream of air passes through the vertical side  54 C over an electronics board located between the vertical side  54 C and the vertical side  54 D, through the vertical side  54 D over an electronics board located between the vertical side  54 D and the vertical side  54 E and through the vertical side  54 E to the plenum  84 . The air then flows from the plenum  84  through the driver electronics blower module  16  to atmosphere. It can thus be seen that heat is continually removed from the driver electronics portion of the test electronics module  12 . 
       FIG. 9  illustrates further components of the oven blower module  14  shown in  FIG. 7 , including a blower bearing mount  90 , a spacer component  92 , a blower motor  96 , a blower motor pulley  98 , a blower pulley  100 , and a drive belt  102 . 
     The blower motor  96  includes a blower motor body  108 , a blower motor stator  110 , a blower motor rotor  112 , and a blower motor output shaft  114 . The blower motor body  108  is mounted in a stationary position on the oven blower frame  20 . The blower motor stator  110  is mounted in a stationary position within the blower motor body  108 . The blower motor output shaft  114  is mounted to the blower motor body  108  for rotation about an axis of the blower motor output shaft  114 . The blower motor rotor  112  is mounted to the blower motor output shaft  114  within the blower motor body  108 . One skilled in the art will appreciate that alternating current is provided to the blower motor stator  110 . The alternating current within the blower motor rotor  112  creates an alternating magnetic field that induces rotation of the blower motor rotor  112  and the blower motor output shaft  114 . 
     The spacer component  92  is located between the blower bearing mount  90  and the oven blower frame  20 , whereafter the blower bearing mount  90  and the spacer component  92  are secured to the oven blower frame  20 . The second blower bearing  72  is held the blower bearing mount  90  and the blower input shaft  74  is held by the second blower bearing  72 . Another blower bearing mount (not shown) is used to mount the first blower bearing  70  ( FIG. 7 ) to the oven blower frame  20 . 
     The blower motor pulley  98  and the blower pulley  100  are mounted to the blower motor output shaft  114  and the blower input shaft  74  respectively so that they rotate in unison therewith. The drive belt  102  forms a closed loop that runs over the blower motor pulley  98  and the blower pulley  100 . An outer surface of the drive belt  102  also runs over an idler roller  116 , which is used to tension the drive belt  102 . The drive belt  102  provides a transmission of power from the blower motor pulley  98  to the blower pulley  100 , and therefore from the blower motor  96  to the centrifugal fan  76 . 
     It should be noted that the terms “pulley” and “belt” should be generically interpreted as encompassing equivalent components such as a “gear” or a “chain,” respectively. 
     The blower pulley  100  is located between the blower bearing mount  90  and the blower bearing mount (not shown) that is used to secure the first blower bearing  70  in  FIG. 7 . The drive belt  102  can however be removed without entirely disconnecting the oven blower  62  ( FIG. 7 ) from the oven blower frame  20 . Bolts and nuts that secure the blower bearing mount  90  and the spacer component  92  to the oven blower frame  20  are undone. Undoing of the nuts and bolts, permits for the spacer component  92  to be removed. After the spacer component  92  is removed, the drive belt  102  can be slipped over the blower bearing mount  90 , without removing the blower bearing mount  90  or the blower bearing mount that is used to secure the first blower bearing  70  in  FIG. 7  from the shaft  74 . A new drive belt (not shown) can then be slipped over the blower bearing mount  90 , whereafter the spacer component  92  is positioned between the blower bearing mount  90  and the oven blower frame  20 , and the blower bearing mount  90  and the spacer component  92  are again secured to the oven blower frame  20  using the bolts and nuts. The new drive belt is then positioned over the blower motor pulley  98  and the blower pulley  100  and is then tensioned with the idler roller  116 . 
       FIG. 10  illustrates a connection scheme by components of an electric tester  120 , including driver boards  122 ,  124 ,  126  and  128 , first and second backplane boards  130  and  132 , and first and second feedthrough boards  134  and  136 . 
     The driver boards  122  and  124  are power boards and the driver boards  126  and  128  are signal boards. Each one of the driver boards  122 , 124 ,  126  and  128  has a respective driver board substrate  138 . The driver board substrates  138  are separate from one another. The driver board substrate  138  of the driver boards  122  and  126  are positioned in an upper horizontal plane and the driver board substrate  138  of the driver boards  124  and  128  are located in a lower horizontal plane. 
     The driver board  122  has a plurality of driver board electric conductors  140 A-F carried by the driver board substrate  138  thereof. The driver boards  124 ,  126  and  128  each has a respective driver board electric conductor  140 G, H and I, respectively carried by a respective driver board substrate  138 . 
     Each one of the backplane boards  130  and  132  has a respective backplane board substrate  142 . The backplane board substrates  142  are positioned in a vertical plane that intersects the horizontal planes of the driver board substrates  138 . The backplane board substrates  142  are separate from one another so that the backplane boards  130  and  132  are not directly connected to one another. 
     The backplane board  130  has a plurality of backplane board electric conductors  144 A-C that are carried by the backplane board substrate  142  thereof. The backplane board  132  has a backplane board electric conductor  144 D carried by the backplane board substrate  142  thereof. 
     The feedthrough boards  134  and  136  each have a respective feedthrough board substrate  146 . The feedthrough board substrate  146  of the feedthrough board  134  may or may not be located in the same horizontal plane as the driver board substrates  138  of the driver boards  122  and  126 . The feedthrough board substrate  146  of the feedthrough board  136  may or may not be located in the same horizontal plane as the driver board substrates  138  of the driver boards  124  and  128 . The feedthrough boards  134  and  136  are located on an opposite side of the plane of the backplane boards  130  and  132  than the driver boards  122 ,  124 ,  126  and  128 . 
     The feedthrough board  134  has a plurality of feedthrough board electric conductors  148 A-I that are carried by the feedthrough board substrate  146  thereof. The feedthrough board  136  has a plurality of feedthrough board electric conductors  148 J-S carried by the feedthrough board substrate  146  thereof. 
     The driver-board electric conductor  140 A extends in a x-direction to an edge  150  of the driver board substrate  138  of the driver board  122 . The edge  150  extends in a z-direction. The driver board electric conductor  140 A connects through connectors and conductors (not shown) of the backplane board  130  to the feedthrough board electric conductor  148 A. The feedthrough board electric conductor  140 A extends in a z-direction and is connected to the backplane board electric conductor  144 D. The backplane board electric conductor  144 D extends in a y-direction and is connected to the feedthrough board electric conductor  148 J. The feedthrough board electric conductor  148 J extends in a z-direction and is connected to the feedthrough board electric conductor  148 K. The feedthrough board electric conductor  148 K extends in a x-direction to an edge  152  of the feedthrough board substrate  146 . The edge  152  extends in a z-direction. 
     It can thus be seen that an end of the feedthrough board electric conductor  148 K at the edge  152  is in a different horizontal and a different vertical plane than an end of the driver board electric conductor  140 A at the edge  150 . The feedthrough board electric conductors  148 A and  148 J provide for connection to a different vertical plane and the backplane board electric conductor  144 D provides for connection to a different horizontal plane. Specifically, the feedthrough board electric conductor  148 K is off-set from a line at right angles to the edge  150  at a terminal connected to the driver board electric conductor  140 A. What should also be noted is that, although the backplane electric conductor  144 D extends in a direction at right angles to a horizontal plane of the driver board substrate  138  of the driver board  122 , the feedthrough board electric conductors  148 A and  148 J do not extend in a direction at right angles to the plane of the driver board substrate  138  of the driver board  122 . 
     A further electric connection is provided by the driver board electric conductor  140 B and the feedthrough board electric conductors  148 B-I. Specifically, the feedthrough board electric conductor  148 C provides for horizontal interconnection in a z-direction to distribute resources from the driver board electric conductor  140 B to multiple locations along an edge  154  of the feedthrough board substrate  146  of the feedthrough board  134 . 
     A similar arrangement is provided by the driver board electric conductor  140 C and the feedthrough board electric conductors  148 L-S. In this arrangement, the backplane board electric conductor  144 A provides for interconnection from an upper horizontal plane of the driver board  122  to a lower horizontal plane of the feedthrough board  136 . 
     As noted, the driver board electric conductors  140 A-C provide resources such as signal, power or ground to the feedthrough boards  134  and  136 . The driver board electric conductors  140 D-F are used for communication between the driver board  122  and the driver boards  124 ,  128  and  126 , respectively. 
     The driver board electric conductor  140 D extends to the edge  140  and is connected to the backplane board electric conductor  144 B. The backplane board electric conductor  144 B extends in a y-direction and is connected to the driver board electric conductor  140 G. The backplane board electric conductor  144 B thus provides for connection from an upper horizontal plane of the driver board  122  to a lower horizontal plane of the driver board  126 . 
     The driver board electric conductor  140 E extends to the edge  150  and is connected to the backplane board electric conductor  144 C. The backplane board electric conductor  144 C extends in a y-direction and is connected to the feedthrough board electric conductor  148 U. The feedthrough board electric conductor  148 U extends in a z-direction and is connected through connectors and conductors (not shown) of the backplane board  132  to the driver board electric conductor  140 I. The backplane board electric conductor  144 C provides interconnection from an upper horizontal plane to a lower horizontal plane and the feedthrough electric conductor  148 U provides interconnection from one vertical plane to another vertical plane. 
     The driver board electric conductor  140 F is connected through connectors and conductors (not shown) of the backplane board  130  to a feedthrough board electric conductor  148 T of the feedthrough board  134 . The feedthrough board electric conductor  148 T extends in a z-direction and is connected through connectors and conductors (not shown) of the backplane board  132  to the driver board electric conductor  140 H. The feedthrough board electric conductor  148 T thus provides for interconnection from one vertical plane to another. 
     All the interconnection schemes that are described with reference to  FIG. 10  originate at the driver board  122 . It should however be understood that similar connection schemes originate from the driver boards  124 ,  126  and  128 . 
     As will be commonly understood, the horizontal planes extend in x- and z-directions and the vertical plane described herein extends in y- and z-directions. It will also be understood that the x-, y-, and z-directions are at angles other than 0° relative to one another, specifically at right angles to one another. It will also be appreciated that vertical and horizontal planes are at an angle other than 0° relative to one another, more specifically at right angles to one another. 
       FIG. 11  shows further components of the electric tester  120 , including first and second sets of backplane connectors  160  and  162 , and a plurality of integrated feedthrough modules  166 . 
     The driver board connectors  164  are secured to the respective driver board substrates  138 . The driver boards  122 ,  126  and  128  are positioned on respective sets of rails  52 C- 52 F. For example, the opposing sides of the driver board  126  are supported on one of the rails  52 E and one of the rails  52 F. 
     The first and second backplane connectors  160  and  162  are secured to opposing sides of either of the substrates  142  and form part of either of the backplane boards  130  or  132 . The backplane board  130  and  132  are mounted to portions of the frame  50 . The driver boards  122 ,  124 ,  126  and  128  are moved on the rails  52 C- 52 F until the driver board connectors  164  engage with the first backplane connectors  160 . Contacts and terminals on the first backplane connectors  160  and the driver board connectors  164  connect the backplane  130  and  132  electrically to the driver boards  122 ,  124 ,  126  and  128 . The second backplane connectors  162  are connected through conductors in the backplane substrate  142  to the first backplane connectors  160 . 
     Each one of the integrated feedthrough modules  166  has a first feedthrough module connector  170  that is secured to the feedthrough board substrate  146 . The first feedthrough module connector  170  has contacts and terminals that connect the feedthrough board, e.g. the feedthrough board  136  electrically to one of the second backplane connectors  162 . 
       FIG. 12  illustrates further components of the integrated feedthrough module  166 , including a second connector  172 , first, second and third pieces of insulation,  174 ,  176  and  178  respectively, a first fastener  180 , a stabilizing piece  182 , and a second fastener  184 . 
     The first insulation piece  174  has a lower surface  186  that is located against an upper surface of the feedthrough board  136  and the second insulation  176  has an upper surface  188  that is located against a lower surface of the feedthrough board  136 . The fastener  180  has a shank  190  and a larger head  192 . The shank  190  is inserted into complementary openings in the first and second insulation pieces  174  and  176 . A lower end of the shank  190  has thread  194  that engages with complementary thread of the second insulation piece  176 . The head  192  is larger than the opening in the first insulation piece  174 . The first fastener  180  thus secures the first and second insulation pieces  174  and  176  to the feedthrough board  136 . 
     The second fastener  184  has a shank  196  and a head  198 . The shank  196  is inserted through an opening in the upper portion of the stabilizing piece  182 . The shank  196  has thread that engages with complementary thread of the first insulation piece  174 . The head  198  engages with the stabilizing piece  182  so that the second fastener  184  secures the stabilizing piece  182  to the first insulation piece  174 . The third insulation piece  178  is located on an inner surface of the stabilizing piece  182 . The stabilizing piece  182  has a connector opening  200  formed therein. The second connector  172  is inserted though the connector opening  200 . The second connector  172  engages structurally and electrically with the feedthrough board  136 . It may also be possible to remove the second connector  172  from the feedthrough board  136  by extracting the second connector  172  out of the connector opening  200 . 
     Referring again to  FIG. 11 , it can be seen that the integrated feedthrough modules  166  are located adjacent one another with a small gap between them. The small gap is filled with an additional insulating piece so that the integrated feedthrough modules  166  and the additional insulating piece form an insulating wall. In another arrangement, the integrated feedthrough modules  166  contact one another so that they form an insulating wall without an additional insulating piece. Because an insulating wall is formed by the integrated feedthrough modules  166 , there is no need for an additional insulating wall to insulate the tester  120  from the second connectors  172 . The connectors  172  can thus be held at higher temperatures of an oven and the electric tester  120  can be maintained at a lower temperature. 
     It may happen from time to time that one of the integrated feedthrough modules  166  fails and has to be replaced. The integrated feedthrough module  166  can be removed by simply extracting the first feedthrough connector module  166  from the corresponding second backplane connector  163 . Another integrated feedthrough module  166  can be then be positioned in its place. The insulating wall will be broken when the failed integrated feedthrough module  166  is removed, but the insulating wall is again restored when the replacement integrated feedthrough module  166  is inserted. 
       FIG. 13  shows a retaining piece  202  that is mounted to the frame  50  by a plurality of fasteners  204 . The retaining piece  202  has a first portion  206  located against and secured to the frame  50 , and a second portion  208  located over a plurality of the integrated feedthrough modules  166 . The retaining piece  202  prevents movement of the integrated feedthrough module  166  relative to the frame  50  when a burn-in board is disconnected from the second connector  172 . 
       FIG. 14  shows the connector  172 , the feedthrough board  136  and a burn-in board  212  in more detail. 
     The connector  172  includes a connector body  214  and first, second, third and fourth conductors  216 ,  218 ,  220  and  222  that are carried by the connector body  214 . 
     The first conductor  216  includes a first connector terminal  224 , a first terminal spring portion  226 , a first connector conductor  228 , a first contact spring portion  230 , and a first connector contact  232 . The connector body  214  has a long outer portion  233  and a short inner portion  235 . The first connector conductor  228  is held between the long outer portion  233  and the short inner portion  235  in an upper half of the connector body  214 . The first terminal spring portion  226  and the first contact spring portion  230  extend from opposing ends of the first connector conductor  228 . The first connector terminal  224  and the first connector contact  232  are located at ends of the first terminal spring portion  226  and the first contact spring portion  230 , respectively. The first connector terminal  224  can be depressed in an upward direction against a spring force that is created by the first terminal spring portion  226 . Similarly, the first connector contact  232  can be depressed in an upward direction against a spring force that is created by the first contact spring portion  230 . Removal of a pressure that depresses the first connector spring terminal  224  or the first connector contact  232  results in downward movement of the first connector terminal  224  or the first connector contact  232 . 
     The second conductor  218  includes a second connector terminal  234 , a second terminal spring portion  236 , a second connector conductor  238 , a second contact spring portion  240 , and a second connector contact  242 . The second connector conductor  238  is located on a lower surface of the short inner portion  235 . The second terminal spring portion  236  and the second contact spring portion  240  extend from opposing ends of the second connector conductor  238 . The second connector terminal  234  and the second connector contact  242  are located at ends of the second terminal spring portion  246  and the second contact spring portion  240 , respectively. The second connector terminal  234  can be depressed in an upward direction against a spring force that is created by the second terminal spring portion  236 . Similarly, the second connector contact  242  can be depressed in an upward direction against a spring force that is created by the second contact spring portion  240 . Removal of a pressure that depresses the second connector spring terminal  234  or the second connector contact  242  results in downward movement of the second connector terminal  234  or the second connector contact  242 . 
     The third conductor  222  includes a third connector terminal  244 , a third terminal spring portion  246 , a third connector conductor  248 , a third contact spring portion  250 , and a third connector contact  252 . The third connector conductor  248  is held between the long outer portion  233  and the short inner portion  235  in a lower half of the connector body  214 . The third terminal spring portion  246  and the third contact spring portion  250  extend from opposing ends of the third connector conductor  248 . The third connector terminal  244  and the third connector contact  252  are located at ends of the third terminal spring portion  256  and the third contact spring portion  250 , respectively. The third connector terminal  244  can be depressed in a downward direction against a spring force that is created by the third terminal spring portion  246 . Similarly, the third connector contact  252  can be depressed in a downward direction against a spring force that is created by the third contact spring portion  250 . Removal of a pressure that depresses the third connector spring terminal  244  or the third connector contact  252  results in upward movement of the third connector terminal  244  or the third connector contact  252 . 
     The fourth conductor  220  includes a fourth connector terminal  254 , a fourth terminal spring portion  256 , a fourth connector conductor  258 , a fourth contact spring portion  260 , a fourth connector contact  264 , and the fourth connector conductor  258  is located on an upper surface of the short inner portion  235 . The fourth terminal spring portion  256  and the fourth contact spring portion  260  extend from opposing ends of the fourth connector conductor  258 . The fourth connector terminal  254  and the fourth connector contact  264  are located at ends of the fourth terminal spring portion  256  and the fourth contact spring portion  260 , respectively. The fourth connector terminal  254  can be depressed in a downward direction against a spring force that is created by the fourth terminal spring portion  256 . Similarly, the fourth connector contact  264  can be depressed in a downward direction against a spring force that is created by the fourth contact spring portion  260 . Removal of a pressure that depresses the fourth connector spring terminal  254  or the fourth connector contact  264  results in upward movement of the fourth connector terminal  254  or the fourth connector contact  264 . 
     Each conductor  216 ,  218 ,  220  and  222  terminates into lips  270 . A gap is defined between the first connector terminal  224  and the third connector terminal  244  and the lips  270  near the first connector terminal  224  and the third connector terminal  244  define a gap that is wider than the gap between the first connector terminal  224  and the third connector terminal  244 . The other lips  270  also define a gap between them that is wider than a respective pair of terminals or contacts near the respective lips. 
     The second connector terminal  234  is behind the first connector terminal  224  in a direction from left-to-right. Similarly, the fourth connector terminal  254  is behind the third connector terminal  244  in a direction from left-to-right. The second connector contact  242  is behind the first connector contact  232  in a direction from right-to-left. Similarly, the fourth connector contact  264  is behind the third connector contact  252  in a direction from right-to-left. 
     The feedthrough board  136  includes a feedthrough board substrate  148  as described with reference to  FIG. 10 , four feedthrough board electric conductors  148  V, U, W and X, and first, second, third and fourth feedthrough board terminals  272 ,  274 ,  275  and  278 . The feedthrough board electric conductors  148  V, U, W and X are similar to the feedthrough board conductors described with reference to  FIG. 10 , except that they are all in the same plane. The first, second, third and fourth feedthrough board terminals  272 ,  274 ,  275  and  278  are connected to the feedthrough board electric conductors  148  U, V, X and W, respectively. The first and second feedthrough board terminals  272  and  274  are located on an upper surface of the feedthrough board substrate  148  with the first feedthrough board terminal  272  located to the right of the second feedthrough board terminal  274 . The third and fourth feedthrough board terminals  275  and  278  are located on a lower side of the feedthrough board substrate  146  with the third feedthrough board terminal  275  to the right of the fourth feedthrough board terminal  278 . 
     In use, a left edge of the feedthrough board  136  is inserted between the lips  270  and urge the first connector contact  232  and the third connector conductor  252  apart. The first connector contact  232  and the third connector conductor  252  are then located on upper and lower surfaces of the feedthrough board  136 . 
     The feedthrough board  136  is then inserted further into the connector  172  until the left edge of the feedthrough board  136  urges the lips  270  near the second connector contact  242  and the fourth connector contact  264  apart. As the feedthrough board  136  moves further into the connector  172 , it comes into a stationary position, wherein the first connector contact  232  makes contact with the first feedthrough board terminal  272 , the second connector contact  242  makes contact with the second feedthrough board terminal  274 , the third connector contact  252  makes contact with the third feedthrough board terminal  275 , and the fourth connector contact  264  makes contact with the fourth feedthrough board terminal  278 . It can thus be seen that four contacts  230 ,  242 .  252  and  264  of the connector  172  are connected to four feedthrough board terminals  272 ,  274 ,  275  and  278  located in the same plane. 
     The burn-in board  212  includes a burn-in board substrate  280 , first, second, third and fourth burn-in board contacts  282 ,  284 ,  286  and  288 , respectively, and first, second, third and fourth burn-in board electric conductors  290 A- 290 D. The first and second burn-in board contacts  282  and  284  are located on an upper side of the burn-in board substrate  280  and the third and fourth burn-in board contacts  286  and  288  are located on a lower side of the burn-in board substrate  280 . The first burn-in board contact  282  is located to the left of the second burn-in board contact  284 . The third burn-in board contact  286  is located to the left of fourth burn-in board contact  288 . 
     In use, the burn-in board  212  is inserted from left to right into the connector  172  between the lips  270  near the first and third connector terminals  224  and  244 . The burn-in boards  212  urge the first and second connector terminals  224  and  244  apart against spring forces by the first and third terminal spring portions  226  and  246 . The first and third connector terminals  224  and  244  slide on upper and lower sides of the burn-in board  212  as the burn-in board  212  is further inserted into the connector  172 . The burn-in board  212  is eventually located in a stationary position wherein the first, second, third and fourth connector terminals  224 ,  234 ,  244  and  254  simultaneously make contact with the first, second, third and fourth burn-in board contacts  282 ,  284 ,  286  and  288 , respectively, all located in the same vertical plane. The burn-in board  212  can also be removed to the left out of the connector  172 . 
     As shown in  FIG. 15 , the connector  172  has a plurality of first conductors  216  and a corresponding plurality of third conductor  222 . Although not shown in  FIG. 15 , it will be appreciated that the connector  172  also has a corresponding plurality of second and third conductors (reference numerals  218  and  220  in FIG.  14 ). 
       FIG. 16  illustrates further components of the burn-in board  212 , including a plurality of sockets  292 , a ground electric conductor  290 G, a power electric conductor  290 P, and two signal electric conductors  290 Si and  290 Sii. The sockets  292  are mounted to the burn-in board substrate  280 . The electric conductors  290 G,  290 P,  290 Si and  290 Sii are similar to the electric conductors  290 A- 290 D described with reference to  FIG. 14 . The electric conductors  290 G,  290 P,  290 Si and  290 Sii connect respective ones of the burn-in board contacts  282  and  284  to terminals within the sockets  292 . The sockets  292  are designed to realeasably hold and retain electronic devices in the form of integrated circuit packages. Each integrated circuit package has a substrate and a die carrying an integrated circuit mounted to the substrate. The package also includes contacts or wire-bonding wires to connect the integrated circuit and the die electrically to the packaged substrate. The package also includes an encapsulant to protect the die. Although not shown in  FIG. 16 , it should be appreciated that there are more ground, power and signal electric conductors than the ground, power and signal electric conductors  290 G,  290 P,  290 Si and  290 Sii that are shown in  FIG. 16 . It will also be appreciated that the third and fourth burn-in board contacts  286  and  288  shown in  FIG. 14  are located on an opposite side of the burn-in board substrate  280  in  FIG. 16  and are similarly connected to the sockets  292  shown in  FIG. 16 . 
     In use, the burn-in board  212  and other similar burn-in boards are inserted through the door opening  46  shown in  FIG. 3  and are located on the rails  52 A and  52 B shown in  FIG. 5 . The door panel  38  is then closed as shown in  FIG. 1 . Power, ground and signals are provided from the driver boards  122 ,  124 ,  126  and  128  in  FIG. 10  to and from the sockets  292  in  FIG. 16 . The temperature gradually raises in an area around the burn-in boards and the temperature is controlled by the oven blower  62 , the heater and the damper described with reference to  FIG. 7 . Once testing of the electronic devices is completed, the door panel  38  is moved into the position shown in  FIG. 4  and the burn-in boards are again removed through the door opening  46 . 
     While certain exemplary embodiments have been described and shown in the accompanying drawings, it is to be understood that such embodiments are merely illustrative and not restrictive of the current invention, and that this invention is not restricted to the specific constructions and arrangements shown and described since modifications may occur to those ordinarily skilled in the art.