Hi list,

I have produced a design for a small wireless device that uses an
18LF252 in a 28-pin SO package. I need to reduce the size of the PCB if
possible, and I am thinking about using an 18LF2520 in a 6mm^2 28 pin
leadless QFN package. Hopefully these boards will be machine assembled
eventually, but I will initially need to be able to hand-solder around a
hundred of these boards, and so that leads me to the obvious question:
can these packages be realistically hand-soldered by someone who is
competent with working with SMT devices? 

I notice that the QFN package has a large ground pad in the centre. I
guess that it is necessary to solder this area to the PCB for mechanical
strength, is that right? Would it be very difficult to solder reflow if
I provided a few vias underneath the device and used a heatgun, paste
etc?

Would I be strongly advised to stick to the larger SO package?

Thanks,

Trevor.


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