Variscite LTD
: 4 Hamelacha St., Lod, Israel
2.3 Insert the M2 screws from the heat spreader top direction.
2.4 Tight the head spreader to the VAR-SOM-MX6 using the supplied nuts.
Recommended torque for tightening the screws and nuts is ~1in-lb (~0.113N-m).
NOTE: due to tolerances of the related components (heat plate, thermal pad,
PCB, i.MX6 processor) there might be some small gap between the heat plate
’s
stands to the PCB itself. It is highly recommended before tightening all 4
nuts/screws to push the heat plate on top of the thermal pad so it will be
squeezed on the processor. Only afterwards tighten the top two screws/nuts,
than the bottom ones close to the SO-DIMM connector while paying attention
when tightening the last screw/nut that there is no extra pressure on the PCB
that might cause it to deform. It is better not to tighten the fourth screw/nut all
the way if you see extra pressure is created on the PCB and use Loctite or
similar glue to lock the screws/nuts. Another alternative is to use a thermal
paste (grease) instead of thermal pad which will bridge the gap between the
processor and the heat plate in different tolerances of the related components.
The thermal paste should have similar thermal conductivity as the thermal pad
of 6.0 watt/m-k (by JIS R2618 / ASTM D2326 standard).
Heat plate assembly sketch
M2 Nut
Heat Spreader
body
VAR-SOM-MX6
PCB
8 mm, M2 Screw
