MSC SM2S-IMX8M User Manual
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1.6 Mechanical Deflection of PCB
For thermal heat dissipation the heat sink needs to be pressed onto the CPU. The higher the pressure the lower is the thermal transition resistance
and consequently the better the thermal cooling. This pressure may result in a slight mechanical bending of the SMARC module.
Production tolerance, material deviation and thermal expansion lead to a range of possible pressure and bending. No pressure with an air gap
between the heat spreader and the chip case needs to be avoided and likewise too high a distortion.
Component types and their distance to the heat spreader mounting holes are considered.
Referring to data sheets of the relevant parts and AEC-Q200 the bending needs to be below 1mm over a length of 90mm. (1.11%)
0.75mm
Figure 1-4: Distance between mounting holes
68mm
