Printed circuit board construction

Claim 2

A composite board member for a multilayer circuit board comprising a dielectric core containing electrical circuitry embedded therein in prearranged pattern bonded between two layers of thermally conducting material, said two layers having a plurality of nonregistering window openings exposing said core, electrically conducting pads and tabs arranged in predetermined geometrical pattern on said core within said window openings of said layers, said pads and tabs being electrically connected to said circuitry, electrically isolated from and physically recessed within said layers, said geometrical pattern permitting the mounting of cased integrated circuit components in crab fashion between groups of tabs in adjoining window openings in thermally conducting contact with said thermally conducting material between window openings.

Claim 3

A composite board member mounting for cased integrated circuit components for use in a multilayer printed circuit board assembly comprising a laminar board having a dielectric core containing embedded electrical circuitry in prearranged pattern, a multimetallic exterior strata on each side of said core, said multimetallic strata consisting of metallurgically joined sheets of different metals including at least a conductor sheet of a metal selected for its electrical conducting qualities and a heat-sink sheet of metal selected for its thermal conducting properties placed with the thermal conducting material on the exterior of the board structure, geometrically arranged and spaced windows in said heat-sink sheet exposing said conductor sheet, said heat-sink sheet having its exterior surface anodized to form an electrically insulating surface, said conductor sheet being selectively etched through within said windows to leave distinct geometrically arranged electrically isolated pads and tabs of said conductor sheet, said pads and tabs being recessed with respect to said exterior surface of said heat-sink, each said pad and tab being individually selectively connected to a portion of said electrical circuitry within said core, said geometrical arrangement of said pads and tabs being such as to permit mounting of cased integrated circuit components of established configuration between proximate rows of tabs of adjacent windows whereby said cased components when terminated on said tabs are inserted electrically into said circuitry and electrically insulated from but thermally in contact with the anodized surface of said heat-sink sheet on the undisturbed portions thereof between said adjacent windows, said pads and tabs also including terminal pads and tabs proximate one edge of said board for electrically inserting said circuitry into said assembly.

Claim 4

A composite board member mounting for cased integrated circuit components for use in a multilayer printed circuit board assembly comprising a laminar board having a dielectric core containing embedded electrical circuitry in prearranged pattern, a multimetallic exterior strata on each side of said core, said multimetallic strata consisting of metallurgically joined sheets of different metals including at least a conductor sheet of a metal selected for its electrical conducting qualities and a heat-sink sheet of metal selected for its thermal conducting properties placed with the thermal conducting material on the exterior of the board structure, geometrically arranged and spaced windows in said heat-sink sheet exposing said conductor sheet, said heat-sink sheet having its exterior surface anodized to form an electrically insulating surface, said conductor sheet being selectively etched through within said windows to leave distinct geometrically arranged electrically isolated pads and tabs of said conductor sheet, said pads and tabs being recessed with respect to said exterior surface of said heat-sink, each said pad and tab being individually selectively connected to a portion of said electrical circuitry within said core, said geometrical arrangement of said pads and tabs being such as to permit mounting of cased integrated circuit components of established configuration between proximate rows of tabs of adjacent windows whereby said cased components when terminated on said tabs are inserted electrically into said circuitry and electrically insulated from but thermally in contact with the anodized surface of said heat-sink sheet on the undisturbed portions thereof between said adjacent windows, said pads and tabs also including terminal pads and tabs proximate one edge of said board for electrically inserting said circuitry into said assembly.

Claim 5

The board structure of claim 2 wherein said pads and tabs are in alternate rows on each side of said board with pads and tabs opposite.

Claim 6

The board structure of claim 2 wherein said windows on one side of said board are offset 50 percent with windows on the opposite side causing heat sink areas between windows on opposite sides to be at maximum separation.

Claim 7

The board structure of claim 4 wherein said pads and tabs are in alternate rows on each side of said board with pads and tabs opposite whereby integrated circuit components attached to said tabs and supported by raised heat-sink separations between windows alternate from side to side in comb fashion.

Claim 8

The structure of claim 5 wherein said cased integrated circuit component devices are in electrical contact with and attached to said tabs and are in thermal contact with said heat-sink sheet.