Electronic circuit card having transient-tolerant distribution planes

• US 6,091,609 A
• Filed: 09/02/1998
• Issued: 07/18/2000
• Est. Priority Date: 05/21/1998
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Kuchta, Douglas Allan, Severson, Paul Steven, Hutson, Maurice Leron
• Primary Examiner(s): Picard, Leo P.
• Assistant Examiner(s): Vigushin, John B.
• Application Number:
  US09/146,010
• Time in Patent Office: 685 Days
• Field of Search: 361/777, 361/780, 361/788, 361/794, 361/729, 174/255, 174/261, 333/12, 333/33, 333/34, 333/246, 333/247, 257/728, 439/61, 439/65, 307/43, 307/80, 307/150, 710/103
• US Class Current: 361/794
• CPC Class Codes: G06F 1/184 Mounting of motherboards
• CPC Class Codes: G06F 1/187 Mounting of fixed and removable disk drives
• CPC Class Codes: G06F 1/188 Mounting of power supply units
• CPC Class Codes: G06F 13/409 Mechanical coupling back panels H05K7/1438
• CPC Class Codes: G11B 33/126 Arrangements for providing electrical connections, e.g. connectors, cables, switches
• CPC Class Codes: H02J 1/001 Hot plugging or unplugging of load or power modules to or from power distribution networks
• CPC Class Codes: H02J 1/102 being switching converters H02J1/108, H02J1/12 take precedence
• CPC Class Codes: H05K 1/0216 Reduction of cross-talk, noise or electromagnetic interference grounding H05K1/0215
• CPC Class Codes: H05K 1/14 Structural association of two or more printed circuits providing electric connection to or between printed circuits H05K1/11, H01R12/00
• CPC Class Codes: H05K 2201/044 Details of backplane or midplane for mounting orthogonal PCBs
• CPC Class Codes: H05K 2201/093 Layout of power planes, ground planes or power supply conductors, e.g. having special clearance holes therein
• CPC Class Codes: H05K 2201/09663 Divided layout, i.e. conductors divided in two or more parts
• CPC Class Codes: H05K 7/1492 having electrical distribution arrangements, e.g. power supply or data communications
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

An electronic system contains a backplane circuit card which supplies power to various modules. Embedded power distribution planes each include one or more islands, each island being associated with a respective module. The island is electrically isolated from the body of the power plane except at a relatively small area, called the power ramp. The electronic current path from the power plane to the module goes through the power ramp and the island. Preferably, a pair of adjacent power planes at +48 VDC and 0 VDC are in the middle layers of the backplane with a ground plane on either side. Signal planes carrying circuit patterns for multiple data signals are deposited as additional layers on either side of the ground planes. The pair of power planes are nearly identical patterns, the differences being the location of power connections for the modules. In particular, the islands and power ramps are located in the same places on each power plane. This causes substantially equal but opposite current densities in the power planes, so that transients induced when a module is removed from or inserted into a powered-on system are significantly reduced. The exemplary embodiment is an intelligent redundant array of independent disks (RAID) storage server having concurrent maintenance capability.

Claims

1. A backplane circuit card for an electronic system, said electronic system having at least one module for plugging into said backplane circuit card, said backplane circuit card comprising:

a first coupling for insertion of said a first module;

a first power plane for distributing a first voltage among a plurality of system components, said plurality of system components including said first module, said first power plane having a first voltage body and a first island, said first island being associated with said first coupling and being electrically isolated from said first voltage body except at a small area, said first voltage body being electrically connected to said first coupling through said first island; and

a second power plane for distributing a second voltage among said plurality of system components, said second power plane lying parallel to and offset from said first power plane, said second power plane having a second voltage body and a second island, said second island being associated with said first coupling and being electrically isolated from said second voltage body except at a small area, said second voltage body being electrically connected to said first coupling through said second island.

2. The backplane circuit card of claim 1, wherein said first and second power planes are separated by a single dielectric layer of substantially uniform thickness.

3. The backplane circuit card of claim 2, wherein said first island is substantially identical in size and shape to said second island, and is located directly opposite said second island across said dielectric layer.

4. The backplane circuit card of claim 2, further comprising:

a first signal plane layer containing a plurality of signal lines for transmission of electronic signals;

a first ground plane lying between said first power plane and said first signal plane layer;

a second signal plane layer containing a plurality of signal lines for transmission of electronic signals, said second signal plane layer lying on a side of said first and second power planes opposite said first signal plane layer and said first ground plane; and

a second ground plane lying between said second signal plane layer and said second power plane.

5. The backplane circuit card of claim 1, further comprising:

a plurality of couplings, each coupling for insertion of a respective module;

wherein said first power plane includes a plurality of islands, each island being associated with a respective coupling for a respective module and being electrically isolated from said first voltage body except at a respective small area, said first voltage body being electrically connected to each respective coupling through each respective island associated with the coupling; and

wherein said second power plane includes a plurality of islands, each island being associated with a respective coupling for a respective module and being electrically isolated from said second voltage body except at a respective small area, said second voltage body being electrically connected to each respective coupling through each respective island associated with the coupling.

6. The backplane circuit card of claim 5, wherein:

said first and second power planes are separated by a single dielectric layer of substantially uniform thickness; and

each island in said first power plane corresponds to a respective island in said second power plane, each corresponding pair of islands in said first power plane and second power plane being associated with a respective coupling, each respective island in said first power plane being substantially identical in size and shape to its corresponding island in said second power plane, and being located directly opposite its corresponding island across said dielectric layer.

7. The backplane circuit card of claim 1, further comprising:

a first signal plane layer containing a plurality of signal lines for transmission of electronic signals; and

a first ground plane lying between said first power plane and said first signal plane layer.

8. The backplane circuit card of claim 1, wherein:

said first voltage body is electrically isolated from said first island except at a ramp of substantially uniform width defined by non-conductive voids; and

said second voltage body is electrically isolated from said second island except at a ramp of substantially uniform width defined by non-conductive voids.

9. The backplane circuit card of claim 1, further comprising:

a second coupling;

wherein said first coupling is for receiving power from a first power source;

wherein said second coupling is for receiving power from a second power source;

wherein said first island is associated with said first and second couplings, said first voltage body being electrically connected to said first and second couplings through said first island; and

wherein said second island is associated with said first and second couplings, said second voltage body being electrically connected to said first and second couplings through said second island.

10. An electronic system, comprising:

a frame for containing a plurality of electronic modules;

a backplane circuit card mounted within said frame, said backplane circuit card distributing electrical power;

at least one power supply module for supplying power to said backplane circuit card;

at least one power consuming module which receives power from said backplane circuit card;

wherein said backplane circuit card comprises;

(a) a first coupling for insertion of a first of said modules;

(b) a first power plane for distributing a first voltage among a plurality of components of said electronic system, said plurality of components including said first module, said first power plane having a first voltage body and a first island, said first island being associated with said first coupling and being electrically isolated from said first voltage body except at a small area, said first voltage body being electrically connected to said first coupling through said first island; and

(c) a second power plane for distributing a second voltage among a plurality of components of said electronic system, said plurality of components including said first module, said second power plane lying parallel to and offset from said first power plane, said second power plane having a second voltage body and a second island, said second island being associated with said first coupling and being electrically isolated from said second voltage body except at a small area, said second voltage body being electrically connected to said first coupling through said second island.

11. The electronic system of claim 10, wherein said first module is capable of being unplugged from said first coupling and replaced with a similar module while electrical power is continually supplied to said backplane circuit card by said power supply module.

12. The electronic system of claim 10, wherein:

said electronic system comprises a plurality of power supply modules for supplying power to said backplane circuit card, each of said plurality of power supply modules being associated with a respective coupling on said backplane circuit card; and

each of said plurality of power supply modules is capable of being unplugged from its associated coupling and replaced with a similar module while electrical power is continually supplied to said backplane circuit card by another of said power supply modules.

13. The electronic system of claim 10, wherein:

said electronic system comprises a plurality of redundant power consuming modules, each of said redundant power consuming modules receiving power from said backplane circuit card, each of said plurality of redundant power consuming modules being associated with a respective coupling on said backplane circuit card;

each of said plurality of redundant power consuming modules performs a function, said function capable of being performed redundantly by at least one other redundant power consuming module; and

each of said plurality of redundant power consuming modules is capable of being unplugged from its associated coupling and replaced with a similar module while said function is continually performed by at least one other of said redundant power consuming modules.

14. The electronic system of claim 10, wherein said first and second power planes of said backplane circuit card are separated by a single dielectric layer of substantially uniform thickness.

15. The electronic system claim 14, wherein:

said first power plane contains a plurality of islands;

said second power plane contains a plurality of islands; and

each island in said first power plane corresponds to a respective island in said second power plane to form a corresponding pair of islands, each corresponding pair of islands being associated with a respective coupling, each respective island in said first power plane being substantially identical in size and shape to its corresponding island in said second power plane, and being located directly opposite its corresponding island across said dielectric layer.

16. The electronic system of claim 14, wherein said backplane circuit card further comprises:

a first signal plane layer containing a plurality of signal lines for transmission of electronic signals;

a first ground plane lying between said first power plane and said first signal plane layer;

a second signal plane layer containing a plurality of signal lines for transmission of electronic signals, said second signal plane layer lying on a side of said first and second power planes opposite said first signal plane layer and said first ground plane; and

a second ground plane lying between said second signal plane layer and said second power plane.

17. The electronic system of claim 10, wherein:

said first voltage body is electrically isolated from said first island except at a ramp of substantially uniform width defined by non-conductive voids; and

said second voltage body is electrically isolated from said second island except at a ramp of substantially uniform width defined by non-conductive voids.