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Advantech SOM-Express Design Guide
Chapter 7 Carrier Board Mechanical Design 97
Chapter 7 Carrier Board Mechanical Design
Guidelines
7.1 SOM-Express Mechanical Dimensions
The PCB size of the SOM-Express module is 125mm x 95mm, COM Express Basic
Module. The PCB thickness may be 2mm to allow high layer count stack-ups and
facilitate a standard ‘z’ dimension between the Carrier Board and the top of the heat-
spreader.
The holes shown in this drawing are intended for mounting the module / heat-
spreader combination to the Carrier Board. An independent, implementation specific
set of holes and spacers shall be used to attach the heat-spreader to the module.
Figure 7-1 shows the SOM-Express module board mechanical dimensions. The unit
is millimeter.
Figure 7-1: SOM-Express Module Board Mechanical Dimensions
Tolerances shall be ± 0.25mm [±0.010”], unless noted otherwise. The tolerances on
the module connector locating peg holes (dimensions [15.50, 6.00] and [16.50,
18.00]) shall be ± 0.10mm [±0.004”].
The 440 pin connector pair shall be mounted on the backside of the PCB and is seen
“through” the board in this view.
The 5 mounting holes shown shall use 6mm diameter pads and shall have 2.7mm
plated holes, for use with 2.5mm hardware. The pads shall be tied to the PCB ground
plane.