Smt Assembly Process; Lead-Free Process; Pcb Design Requirements; Pcb Surface Finish - Sierra Wireless AirPrime HL Series Customer Process Manuallines

4. SMT Assembly Process

This section presents information and recommendations for the industrial assembly of the AirPrime
Snap-in Socket on the application.
Note: The AirPrime Snap-in socket frame should be assembled by reflow process.
4.1.

Lead-Free Process

In compliance with directive 2011/65/CE, Sierra Wireless products do not contain the following
hazardous substances:
 mercury (Hg),
 lead (Pb),
 cadmium (Cd),
 hexavalent chromium (Cr+6),
 polybrominated diphenyl ether (PBDE),
 polybrominated biphenyl (PBB).
The AirPrime Snap-in Sockets are manufactured with RoHS compliant components and processes.
4.2.

PCB Design Requirements

4.2.1.

PCB Surface Finish

The PCB surface finish recommended is Electroless Nickel, immersion Gold. Organic Solderability
Preservative (OSP) may also be used.
Caution:
Hot Air Solder Leveled finish (HASL) is not recommended because the process does not give
consistent solder volumes on each pad because of poor pad flatness.
4.2.2.

Footprint

In order to produce high assembly yields and a reliable solder joint, footprint design should match
either Figure 7 or Figure 9 below. These footprints are compatible for either soldering the module on
its own or for soldering a Snap-in Socket.
Mechanical drawings of the module's footprint are available in the Product Technical Specification of
each product as listed in section 1.2 Reference Documents.
The following should also be noted when designing the footprint:
 The 64 inner pads and the 8 corner pads are ground pads. Not all of these are present on the
Snap-in Socket. Moreover, JTAG pins are also not present on the Snap-in Socket.
 Sierra Wireless suggests that customers place a copper pad under the Polarity mark to avoid
any risk of short circuits between this pin and the customer layout; however, there is no need
to solder it. This mark also eases visual confirmation of the correct orientation of the module.
 Manufacturing tolerance for copper pads is 30 µm.
4115102 Rev 6.0 June 15, 2017 14