INTEGRATED BACKPLANE

Abstract: An electronic system is packaged to provide a single etched backplane. Bus bars are physically fastened to bushings which are soldered to the backplane power etch lines to provide power to the system. Printed circuit boards are plugged into connectors mounted on the backplane for receiving power end transfer­ ring logic signals between printed circuit boards. A number of power supplies are plugged into connectors mounted on the bus bars for transmitting power, and plugged into connectors for transferring logic signals.

Description: RELATED APPLICATION The following U.S. patent application filed on an even date with the instant application and assigned to the same assignee as the instant application is related to the instant application and is incorporated herein by reference. "Power Supply Contact" by John W. Blomstedt, Wesley F. Irving and Mark S. Pusateri, having U.S. Patent No. 4862326. BACKGROUND OF THE INVENTION Field of the Invention This invention relates to the mechanical packaging of electronic assemblies, and more specifically to the use of an integrated backplane into which are plugged both logic boards and power supplies. Description of the Prior Art Electronic systems, particularly data processing systems, are packaged by having a separate logic backplane having connections mounted in the backplane with selected connector pins coupled together by a copper etch on the surface of the backplane. Separate power supplies are mounted elsewhere in the cabinet and connected to the logic backplane with heavy copper cable which carry high current-low voltage. Also, signal lines between the power supplies and the logic require separate multiconductor cables. This prior art system usually requires a protective enclosure for all power supplies. Another disadvantage of the prior art design is that power supplies cannot be parallelled for power sharing due to the requirement for multiple sensing. Multiple sensing requires that the power supplies provide control signals to each other as well as to the logic to provide for balanced loading of the power supplies. The long wire runs add to the electromagnetic interference and radio frequency interference signals. The US patent 4,511,950 (= EP-A-0 129 982) discloses a back panel assembly which permits supply of power to printed circuit boards (PCB's) that are plugged into PCB connectors on one side of the back panel. Various pins of the PCB connectors are coupled to the power supply studs extending through the panel via printed circuit conductors (tracks). Power supply buses extend across the reverse side of the back panel and are connected to selected studs to apply particular supply voltages thereto. Different embodiments and alternative versions which are disclosed in this reference discuss the use of one power supply board for each PCB or for a respective group of PCB's. In another version, the associated power supply board must supply the power to its group through printed circuit tracks, according to the teaching of this reference, prior to delivery of the supply voltages to the associated buses. Thus, so far as it is material for the subject application, the above mentioned reference merely discloses the possibility of connecting a single power supply board to a group of utilization boards by employing the printed circuit tracks of the back panel to carry the various supply voltages to respective buses attached to the back panel. The buses, in turn, deliver the supply voltages to the utilization PCB's. Accordingly, parts of the printed circuits of the back panel must carry the heavy currents of the power supply boards prior to the distribution of the currents via the buses. OBJECTS OF THE INVENTION Accordingly, it is a primary object of the invention to provide an improved mechanical packaging system. It is an object of the invention to have an improved system which does not require cables between the power and the logic. It is also an object of the invention to have an improved system having a minimum voltage drop between the power and the logic. It is yet another object of the invention to provide for redundant parallel operation of the power supplies. It is still another object of the invention to provide for short signal lines between the power and the logic. SUMMARY OF THE INVENTION According to the invention there is provided an electronic system as defined in claim 1. An electronic system is packaged with an integrated multilayer backplane. Each of the logic printed circuit boards plugs into their respective connector mounted on the backplane. Multiple power supplies also bring the signal lines to a printed circuit board connector mounted on the power supply which plugs into a mating connector mounted on the backplane. Voltage and ground are distributed to areas of the backplane by means of bus bars. Special connectors are bolted to the bus bars and mesh with corresponding bus bars mounted on the power supplies. All printed circuit boards and power supplies are readily pluggable and unpluggable from the single integrated backplane. BRIEF DESCRIPTION OF THE DRAWINGS The novel features which are characteristic of the invention are set forth with particularity in the appended claims. The invention itself, however, both as to organization and operation may best be understood by reference to the following description in conjunction with the drawings in which: Figure 1 shows a breakout of the assembly of the packaging including the integrated backplane; Figure 2 shows the integrated backplane with the bus bars bolted to it; and Figure 3 shows how the power supply plugs into a connector bolted to the bus bars. DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to Figure 1, an electronic system 1 includes an integrated backplane 2 into which are plugged a number of etched printed circuit board assemblies 4 and typically four power supplies 6, one of which is shown. The backplane 2 includes a multilayer printed circuit board 3 upon which are mounted a number of connectors 8 into which corresponding printed circuit board assemblies 4 are plugged. Also mounted on board 3 are typically four connectors 10, one for each power supply 4. The board 3 includes etched signal lines between selected pins of the various connectors 8, etched signal lines between selected pins of the various connectors 10 and etched signal lines between selected pins of connectors 8 and 10. In addition, power is provided to selected pins by means of a ground etch 7 and a voltage distribution etch 5. The etched lines are not shown in the drawing since their physical makeup and use are well known in the industry. Electronic system 1 also includes a guide 18 which fastens to backplane 2 and provides lateral support for the board assemblies 4 by means of channels 20. Board assemblies 4 include an edge connector 9 which plugs into the respective connector 8. An enclosure 22 shields and provides lateral support for the typically four power supplies 6. Figure 2 shows an outside bottom view of the backplane 2 showing bus bars 16 which distribute ground and bus bars 14 which distribute voltage. The bus bars 14 and 16 are coupled physically and electrically to board 3 by means of a number of bushings 25. Bushings 25 are soldered as shown in Figure 2A to the respective ground and voltage etches. Bus bars 14 and 16 are bolted to bushings 25 by bolts 24. A connector 12 is bolted to each bus bar by two bolts 26. Each power supply 6 of Figure 1 includes ground and voltage male connectors 30 which plug into connectors 12 to apply ground and voltage to bus bars 16 and 14, respectively. Also, edge connector 32 plugs into connector 10 to couple the power supply control logic to other power supplies 6 and control logic to selected board assemblies 4 control logic. Figure 3 shows the detailed assembly of power connector 12 mounted to bus bars 14 or 16 by means of bolts 26. Male connector 30 is fastened to power supply 6 and plugs into power connector 12.

Claims: An electronic system consisting of a plurality of printed circuit boards (4) and a plurality of power supplies (6), the system further having a backplane (2) for coupling together said boards and power supplies to provide distribution among them of power (voltage and ground) and signals, including power control signals; a) said backplane comprising a plurality of bus bars (14, 16) for carrying said power and an etched line (5, 7) connected to each of said bus bars for distributing said power; said backplane further comprising a plurality of first connectors (8) for transmitting and receiving said power and signals, a plurality of second connectors (10) for transmitting and receiving said power control signals, and a plurality of third connectors (12) for receiving said power; the system further having b) a fourth connector (30) connected to each of said power supplies and mating with a third connector to transmit power generated by said power supply to said bus bars; c) a fifth connector (32) connected to each of said power supplies and mating with a second connector for transferring said power control signals between said backplane and said power supplies; and d) a sixth connector (9) connected to each of said boards and mating with a first connector for transferring said control signals between said backplane and said board and for transmitting power from said bus bars to said board. The electronic system of claim 1 wherein said backplane is further characterized by: comprising a single board (3) including etched signal lines and etched power lines (5, 7); a plurality of bushings (25) for connecting said bus bars to said etched power lines, each having a fastener 24 and being soldered to one of said etched power lines; and said bus bar being coupled to said bushings by said fastener.

Inventors: BLOMSTEDT, JOHN W., IRVING, WESLEY F., ROUDENKO, VLADIMIR, YOSHIDA, PAUL S.
Applicants: BULL HN INFORMATION SYSTEMS INC.
Application year: 1986
Main classification: H05K7
IPC codes: H05K1, H05K7, H01B7, H01R4