Independent Loading Mechanism (Ilm); Design Concept - Intel BX80605X3440 - Quad Core Xeon X3440 Reference

Independent Loading Mechanism (ILM)

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Independent Loading
Mechanism (ILM)
The Independent Loading Mechanism (ILM) provides the force needed to seat the
1156-LGA land package onto the socket contacts. The ILM is physically separate from
the socket body. The assembly of the ILM to the board is expected to occur after wave
solder. The exact assembly location is dependent on manufacturing preference and test
flow. See the Manufacturing Advantage Service collateral for this platform for additional
guidance.
Note:
The ILM has two critical functions: deliver the force to seat the processor onto the
socket contacts and distribute the resulting compre ssive load evenly through the socket
solder joints.
Note: The mechanical design of the ILM is integral to the overall functionality of the LGA1156
socket. Intel performs detailed studies on integration of processor package, socket and
ILM as a system. These studies directly impact the design of the ILM. The Intel
reference ILM will be "build to print" from Intel controlled drawings. Intel recommends
using the Intel Reference ILM. Custom non-Intel ILM designs do not benefit from Intel's
detailed studies and may not incorporate critical design parameters.
4.1

Design Concept

The ILM consists of two assemblies that will be procured as a set from the enabled
vendors. These two components are ILM cover assembly and back plate. To secure the
two assemblies, two types of fasteners are required a pair (2) of standard 6-32 thread
screws and a custom 6-32 thread shoulder screw. The reference design incorporates a
T-20 Torx* head fastener. The Torx* head fastener was chosen to ensure end users do
not inadvertently remove the ILM assembly and for consistency with the LGA1366
socket ILM. The Torx* head fastener is also less susceptible to driver slippage. Once
assembled the ILM is not required to be removed to install / remove the motherboard
from a chassis.
4.1.1 ILM Cover Assembly Design Overview
The ILM Cover assembly consists of three major pieces: load lever, load plate and the
hinge frame assembly.
All of the pieces in the ILM cover assembly except the hinge frame and the screws used
to attach the back plate are fabricated from stainless steel. The hinge frame is plated.
The frame provides the hinge locations for the load lever and load plate. An insulator is
pre-applied to the bottom surface of the hinge frame.
The cover assembly design ensures that once assembled to the back plate the only
features touching the board are the shoulder screw and the insulated hinge frame
assembly. The nominal gap of the load plate to the board is ~1 mm.
Thermal/Mechanical Specifications and Design Guidelines 29