LGA775 Socket Heatsink Loading
Thermal and Mechanical Design Guidelines
79
Figure
7-7. Example: Defining Heatsink Preload Meeting Board Deflection Limit
A.2.5
Additional Considerations
Intel recommends to design to {d_BOL - d_ref = 0.15mm} at BOL when EOL
conditions are not known or difficult to assess.
The following information is given for illustration only. It is based on the reference
keep-out, assuming there is no fixture that changes board stiffness:
d_ref is expected to be 0.18 mm on average, and be as high as 0.22 mm
As a result, the board should be able to deflect 0.37 mm minimum at BOL
Additional deflection as high as 0.09 mm may be necessary to account for additional
creep effects impacting the board/clip/fastener assembly. As a result, designs could
see as much as 0.50 mm total downward board deflection under the socket.
In addition to board deflection, other elements need to be considered to define the
space needed for the downward board total displacement under load, like the potential
interference of through-hole mount component pin tails of the board with a
mechanical fixture on the back of the board.
NOTES:
1.
The heatsink preload must remain below the maximum load limit of the
package at all times (Refer to processor datasheet)
2.
Board deflection should not exceed motherboard manufacturer specifications.
Summary of Contents for Celeron Dual-Core E1000 Series
Page 10: ...10 Thermal and Mechanical Design Guidelines...
Page 26: ...Processor Thermal Mechanical Information 26 Thermal and Mechanical Design Guidelines...
Page 68: ...ATX Thermal Mechanical Design Information 68 Thermal and Mechanical Design Guidelines...
Page 86: ...Heatsink Clip Load Metrology 86 Thermal and Mechanical Design Guidelines...
Page 88: ...Thermal Interface Management 88 Thermal and Mechanical Design Guidelines...
Page 120: ...Legacy Fan Speed Control 120 Thermal and Mechanical Design Guidelines...
Page 126: ...Fan Performance for Reference Design 126 Thermal and Mechanical Design Guidelines...
Page 127: ...Fan Performance for Reference Design Thermal and Mechanical Design Guidelines 127...
