Assembly instructions
SMT pick and place
ConnectCore® 8X System-on-Module Hardware Reference Manual
104
optimal solder paste volume.
SMT pick and place
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Placement nozzle: Largest available on the machine
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Nozzle pick surface: Center of shield
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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
SAC305 No-Clean (Alpha OM-340 or equivalent)
Stencil thickness
0.15 mm / 5 mil
Stencil diameter
1.47 mm / 58mil
Paste alignment
20% maximum off center of the pad
PnP
Placement nozzle
Largest available on machine
Nozzle pick surface
Shield center
Speed
Slowest possible with PnP machine
Placement sequence
Last, if possible
Placement alignment 10% maximum off center of pad
Reflow
See the
Reflow profile
Digi recommends the following:
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SoM temperature below 238°C during reflow cycle.
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Time Above Liquidus (TAL) between 55 and 65 seconds.
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Use of 40AWG K-type thermal couple and M.O.L.E. or equivalent thermal profiler.
