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 ...............................................................................14
2 Processor Thermal/Mechanical Information .........................................................17
2.1 Mechanical Requirements ......................................................................17
2.1.1 Processor Package...................................................................17
2.1.2 Heatsink Attach ......................................................................19
2.1.2.1 General Guidelines....................................................19
2.1.2.2 Heatsink Clip Load Requirement..................................19
2.1.2.3 Additional Guidelines.................................................20
2.2 Thermal Requirements ..........................................................................20
2.2.1 Processor Case Temperature.....................................................20
2.2.2 Thermal Profile .......................................................................21
2.2.3 T
CONTROL
..................................................................................23
2.3 Heatsink Design Considerations..............................................................24
2.3.1 Heatsink Size..........................................................................25
2.3.2 Heatsink Mass.........................................................................25
2.3.3 Package IHS Flatness...............................................................26
2.3.4 Thermal Interface Material........................................................26
2.4 System Thermal Solution Considerations .................................................27
2.4.1 Chassis Thermal Design Capabilities...........................................27
2.4.2 Improving Chassis Thermal Performance ....................................27
2.4.3 Summary...............................................................................28
2.5 System Integration Considerations..........................................................28
3 Thermal Metrology ..........................................................................................29
3.1 Characterizing Cooling Performance Requirements ....................................29
3.1.1 Example ................................................................................31
3.2 Processor Thermal Solution Performance Assessment ................................31
3.3 Local Ambient Temperature Measurement Guidelines.................................32
3.4 Processor Case Temperature Measurement Guidelines ...............................34
4 Thermal Management Logic and Thermal Monitor Feature .....................................35
4.1 Processor Power Dissipation...................................................................35
4.2 Thermal Monitor Implementation ............................................................35
4.2.1 PROCHOT# Signal ...................................................................36
4.2.2 Thermal Control Circuit ............................................................36
4.2.2.1 Thermal Monitor .......................................................36
4.2.2.2 Thermal Monitor 2 (TM2) ...........................................37
4.2.3 Operation and Configuration .....................................................38
4.2.4 On-Demand Mode ...................................................................39