Board Layout; Lga1366 Socket Land Pattern (Top View Of Board) - Intel X3350 - Xeon 2.66 Ghz 12M L2 Cache 1333MHz FSB LGA775 Quad-Core Processor Design Manual

LGA1366 Socket
3.1

Board Layout

The land pattern for the LGA1366 socket is 40 mils X 40 mils (X by Y), and the pad size
is 18 mils. There is no round-off (conversion) error between socket pitch (1.016 mm)
and board pitch (40 mil) because these values are equivalent.
In general, metal defined (MD) pads perform better than solder mask defined (SMD)
pads under thermal cycling, and SMD pads perform better than MD pads under
dynamic stress. Recommendations for pad definition on a per pad basis do not exist for
the LGA1366 socket.
The 40 mil spacing results in a reduced drill keepout as compared to previous
platforms. Drill keepout is explained in section 3.2.1 of the Intel
Design Guide (PDG). Select PCB suppliers are capable of producing 40 mil spacing.
Figure 3-3.

LGA1366 Socket Land Pattern (Top View of Board)

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August 2010
Order Number: 323107-002US
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Intel Xeon Processor C5500/C3500 Series and LGA1366 Socket
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Xeon 5500 Platform
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