WIN Enterprises MB-73440, User Manual, Page: 26 / 82

Copyright © WIN Enterprises, Inc. MB-73440
24
For the Compact form factor a heat-spreader should not use the Module mounting holes as the only
attachment points to a Module. The intent is to be able to provide a Module and heat-spreader as an
assembly that can then be mounted to a Carrier without having to break the thermal interface between
the Module components and the heat-spreader.
The standoffs should be mounted on the Carrier Board. The height of the standoff is dependent on the
stack height of the Carrier Board connector (5 mm or 8mm).
The overall Module height from the bottom surface of the Module board to the heat-spreader top
surface shall be 13 mm for the Mini, the Compact, the Basic and the Extended Modules.
The Module PCB and heat-spreader plate thickness are vendor implementation specific, however, a 2
mm PCB with a 3 mm heat-spreader may be used which allows use of readily available standoffs.
Tolerances (unless otherwise specified):
Z (height) dimensions should be
±
0.8mm [
±
0.031”] from top of Carrier Board to top of heatspreader.
Heat-spreader surface should be flat within 0.2mm [.008"] after assembly.
Interface surface finish should have a maximum roughness average (Ra) of 1.6
μ
m [63
μ
in].
The critical dimension in Figure 6-10 is the Module PCB bottom side to heat-spreader topside. This
dimension shall be 13.00mm
±
0.65mm [
±
0.026”].
Figure below shows a cross section of a Module and heat-spreader assembled to a Carrier Board using
the 5mm stack height option. If 8mm Carrier Board connectors are used, the overall assembly height
increases from 18.00mm to 21.00mm.