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US5625227A Expired / Lapsed US ⏱️ 0.0 years remaining

Circuit board-mounted IC package cooling apparatus

Assignee: Dell USA LP
•
Filing: 1995-01-18
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Granted: 1997-04-29
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Expires: 2015-01-18
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Abstract

Abstract In a circuit board/IC package assembly the die cavity in the IC package body portion is filled with a thermally conductive liquid to substantially facilitate the transfer of operational die heat toward the inner, lid side of the IC package that faces the circuit board. To dissipate the die heat received by the die cavity lid, a spaced series of metal-plated through holes are formed in the circuit board. The metal plating portions of the through holes are engaged with an internal ground plane structure within the circuit board, and are thermally coupled to the IC package die cavity lid. Accordingly, during operation of the IC package, die heat is conducted to the ground plane structure sequentially through the die cavity liquid, the cavity lid, and the metal-plated through holes. In another embodiment of the assembly, the circuit board through holes are replaced with a circuit board opening through which a heat sink structure passes, the heat sink structure being thermally coupled on one side thereof to the die cavity lid. The other side of the heat sink structure engages a metal chassis section which interiorly engages the outer plastic housing wall of a computer.

Inventors

  • 👤 Scott Estes
  • 👤 Deepak Swamy

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 07:02
CPC Classifications
H; H05; H05K; H05K1/00; H05K1/02; H05K1/0201; H05K1/0203; H05K1/0207; H10; H10W; H10W40/00; H10W40/20; H10W40/22; H10W40/226; H10W40/228; H10W40/70; H05K1/0204; H05K1/0206; H05K2201/00; H05K2201/06; H05K2201/066; H05K2201/10; H05K2201/10227; H05K2201/10416; H05K2201/10431; H05K2201/10439; H05K2201/10477; H05K2201/10613; H05K2201/10621; H05K2201/10704; H05K3/00; H05K3/0058; H05K3/0061; H05K3/40; H05K3/42; H05K3/429; H05K3/46; H05K3/4611; H05K3/4641; H10W70/00; H10W70/60; H10W70/67; H10W70/68; H10W70/682; H10W70/685; H10W72/00; H10W72/071; H10W72/075; H10W72/07551; H10W72/07554; H10W72/50; H10W72/541; H10W72/547; H10W74/00; H10W90/00; H10W90/701; H10W90/751; H10W90/754

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 152 words
Electronic apparatus comprising: a circuit board having first and second opposite sides; an IC package mounted on said first side of said circuit board and including: a body portion having a first side facing said first side of said circuit board and having an opening, an opposite second side, and a cavity extending from said opening through said body portion toward said second side thereof, a heat generating die operatively mounted in said cavity and spaced apart from said opening toward said second side of said body portion, a lid member sealingly received in said opening, and a thermally conductive liquid disposed within and filling said cavity and serving to conduct die heat therethrough to said lid member; and heat dissipation means, thermally coupled to said lid member and extending therefrom through said circuit board, for conducting die heat from said body portion through said circuit board toward said second side thereof.
Claim 2
Dependent Claim 152 words
Electronic apparatus comprising: a circuit board having first and second opposite sides; an IC package mounted on said first side of said circuit board and including: a body portion having a first side facing said first side of said circuit board and having an opening, an opposite second side, and a cavity extending from said opening through said body portion toward said second side thereof, a heat generating die operatively mounted in said cavity and spaced apart from said opening toward said second side of said body portion, a lid member sealingly received in said opening, and a thermally conductive liquid disposed within and filling said cavity and serving to conduct die heat therethrough to said lid member; and heat dissipation means, thermally coupled to said lid member and extending therefrom through said circuit board, for conducting die heat from said body portion through said circuit board toward said second side thereof.
Claim 3
Dependent Claim 14 words
The electronic apparatus of claim 1 wherein said thermally conductive liquid is chemically inert.
Claim 4
Dependent Claim 14 words
The electronic apparatus of claim 1 wherein said thermally conductive liquid is electrically insulative.
Claim 5
Dependent Claim 19 words
The electronic apparatus of claim 1 wherein said thermally conductive liquid has a relatively low coefficient of thermal expansion.
Claim 6
Dependent Claim 26 words
The electronic apparatus of claim 1 wherein said thermally conductive liquid is chemically inert, is electrically insulative, and has a relatively low coefficient of thermal expansion.
Claim 7
Dependent Claim 16 words
The electronic apparatus of claim 5 wherein said thermally conductive liquid is an inert fluorocarbon-based liquid.
Claim 8
Dependent Claim 16 words
The electronic apparatus of claim 5 wherein said thermally conductive liquid is a vacuum pump liquid.
Claim 9
Dependent Claim 44 words
The electronic apparatus of claim 1 wherein: said circuit board has a metal ground plane structure disposed between said first and second opposite sides thereof, and said heat dissipation means engage said metal ground plane structure and are operative to transfer die heat thereto.
Claim 10
Dependent Claim 46 words
The electronic apparatus of claim 8 wherein said heat dissipation means include: a spaced series of through holes extending between said first and second opposite sides of said circuit board and having metal linings thermally interconnected between said lid member and said metal ground plane structure.
Claim 11
Dependent Claim 50 words
The electronic apparatus of claim 9 wherein: the metal linings of said through holes are thermally connected to said lid member by a heat spreader plate interposed between the metal linings and said lid member, and the metal linings of said through holes directly engage said metal ground plane structure.
Claim 12
Dependent Claim 34 words
The electronic apparatus of claim 9 further comprising: heat sink means secured to said second side of said circuit board and operative to receive die heat from the metal linings of said through holes.
Claim 13
Dependent Claim 33 words
The electronic apparatus of claim 1 further comprising: heat sink means, disposed on said second side of said body portion, for receiving die heat conducted through said body portion said second side thereof.
Claim 14
Dependent Claim 38 words
The electronic apparatus of claim 1 further comprising: sensing means disposed in said cavity and operative to output a control signal indicative of a temperature of said thermally conductive liquid in excess of a predetermined maximum temperature thereof.
Claim 15
Dependent Claim 14 words
The electronic apparatus of claim 13 wherein: said sensing means include a pressure transducer.
Claim 16
Dependent Claim 57 words
The electronic apparatus of claim 1 wherein said heat dissipation means include: an opening extending through said circuit board between said first and second opposite sides thereof and generally aligned with said lid member, and heat sink means, thermally connected to said lid member and extending through said circuit board opening, for receiving and dissipating die heat.
Claim 17
Dependent Claim 60 words
The electronic apparatus of claim 15 wherein: said electronic apparatus further comprises a plastic computer housing wall having an inner side surface spaced apart from and facing said second side wall of said circuit board, and a metal chassis structure engaging said inner side surface, and said heat sink means are in thermally conductive engagement with said metal chassis structure.
Claim 18
Dependent Claim 16 words
The Electronic apparatus of claim 1 wherein said thermally conductive liquid is a vacuum pump fluid.

References Cited (Backward Citations)

US4396936A Cited
US5270572A Cited
US5305184A Cited
US5455458A Cited
US5448108A Cited
US5373417A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2000-04-28 2000-10-28 2001-04-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2004-04-28 2004-10-28 2005-04-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2008-04-28 2008-10-28 2009-04-29 $7700.00 Window Closed / Lapsed

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