Thermal and Mechanical Design Guidelines 3
Contents
1 Introduction...................................................................................................11
1.1 Document Goals and Scope ...................................................................11
1.1.1 Importance of Thermal Management..........................................11
1.1.2 Document Goals......................................................................11
1.1.3 Document Scope.....................................................................12
1.2 References ..........................................................................................13
1.3 Definition of Terms...............................................................................13
2 Processor Thermal/Mechanical Information .........................................................15
2.1 Mechanical Requirements ......................................................................15
2.1.1 Processor Package...................................................................15
2.1.2 Heatsink Attach ......................................................................17
2.2 Thermal Requirements ..........................................................................18
2.2.1 Processor Case Temperature.....................................................18
2.2.2 Thermal Profile .......................................................................19
2.2.3 T
CONTROL
..................................................................................20
2.3 Heatsink Design Considerations..............................................................21
2.3.1 Heatsink Size..........................................................................22
2.3.2 Heatsink Mass.........................................................................22
2.3.3 Package IHS Flatness...............................................................23
2.3.4 Thermal Interface Material........................................................23
2.4 System Thermal Solution Considerations .................................................24
2.4.1 Chassis Thermal Design Capabilities...........................................24
2.4.2 Improving Chassis Thermal Performance ....................................24
2.4.3 Summary...............................................................................25
2.5 System Integration Considerations..........................................................25
3 Thermal Metrology ..........................................................................................27
3.1 Characterizing Cooling Performance Requirements ....................................27
3.1.1 Example ................................................................................28
3.2 Processor Thermal Solution Performance Assessment ................................29
3.3 Local Ambient Temperature Measurement Guidelines.................................29
3.4 Processor Case Temperature Measurement Guidelines ...............................32
4 Thermal Management Logic and Thermal Monitor Feature .....................................33
4.1 Processor Power Dissipation...................................................................33
4.2 Thermal Monitor Implementation............................................................33
4.2.1 PROCHOT# Signal ...................................................................34
4.2.2 Thermal Control Circuit ............................................................34
4.2.3 Thermal Monitor 2...................................................................35
4.2.4 Operation and Configuration .....................................................36
4.2.5 On-Demand Mode ...................................................................37
4.2.6 System Considerations.............................................................37
4.2.7 Operating System and Application Software Considerations...........38
4.2.8 THERMTRIP# Signal.................................................................38
4.2.9 Cooling System Failure Warning ................................................38