Assembly instructions
Coplanarity
ConnectCore 6 Plus Hardware Reference Manual
94
Coplanarity
The coplanarity measured on the ConnectCore 6 Plus is <0.003" bow and twist (98% confidence
interval). It is important that the carrier board is also coplanar. If the carrier board is thinner than the
ConnectCore 6 Plus it is recommended that the assembly be supported during the reflow process, i.e.
reflow fixture should be used to minimize the potential bow of the carrier card.
Bow and twist measurements have been done with SmartScope Flash 500 equipment which has a Z
accuracy up to (2.0 + 8L/1000) µm.
SMT pick and place
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Placement Nozzle: Large is available on the machine
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Nozzle Pick Surface: Center of Shield on i.MX6QP SOM
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Placement Speed: Slowest speed for the machine
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Placement alignment: 10% of pad diameter (compensating for module weight and supporting
alignment). The module should be placed last as part of the assembly/mounting process to
eliminate unexpected shifting.
SMT process parameter reference
Process
SMT process
Specification recommendations
Screen print Solder paste
Leaded: Indium NC-SMQ92J / Lead-free: Alpha OM-340
Stencil thickness
0.15 mm / 5 mil
Stencil diameter
1.47 mm / 58mil
Paster alignment
25% off the pad (offset <0.25* diameter
PnP
Placement nozzle
0>15 mm vacuum
Nozzle Pick Surface
PnP cap center
Speed
Slowest speed for the machine
Placement Sequence
Place the SoM last
Placement Alignment
50% off the pad (offset <.5* diameter)
Reflow
Belt speed
0.6-1.1 m/sec
Refer to SMT profile recommendation in the next page
Reflow profile
Time Above Liquidous (TAL) is recommended to be between 56 to 63 seconds. Use of 40AWG K-type
thermal couple and M.O.L.E or equivalent thermal profiler is recommended. The first recommended
thermal probe location is on the outer row of pads, to be on the out most row of pins preferably a
ground pad. The second thermal probe location is on the inner row of pads preferably a signal pad.
The following image shows the reflow profile based on a ten-zone oven, with SAC 305 Lead-Free
Solder Paste (Alpha OM-340).
