Reference Manual

Assembly instructions SMT pick and place
ConnectCore® 8X System-on-Module Hardware Reference Manual --
Preliminary
103
SMT pick and place
n Placement nozzle: Largest available on the machine
n Nozzle pick surface: Center of shield
n Placement speed: Slowest speed for the machine
n 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
Reflow profile
Digi recommends the following:
n SoM temperature below 238°C during reflow cycle.
n Time Above Liquidus (TAL) between 55 and 65 seconds.
n Use of 40AWG K-type thermal couple and M.O.L.E. or equivalent thermal profiler.