I've done 0.5mm pitch TQFP on home-fabbed PCBs with an iron. Heck, I've done 0.4mm pitch too. It's easy if you know how. Here's how. You'll need:
pen flux solder wire iron with normal-sized chisel or hoof tip (I use chisel) Procedure: Pen flux the pads on the PCB and the pins on the QFP (top and bottom). Place a small amount of solder on your iron. Place the QFP where you want it. Hold it there somehow. I use my fingers. You could also use tape or a tripod-like hold-down. Touch the iron to one corner of the qfp. It's OK if you get more than one pin soldered, just tack down that corner. Place a small amount of solder on your iron. Verify the QFP is still in the right place and tack the opposite corner. Verify (again). Put a small blob of solder on your iron and just run it down one of the un-tacked rows of pins. This will solder all the pins and probably short a few. Add more solder to the iron as needed, but you don't want to add it all at once. Repeat for the other four sides. Pen flux the shorts and remove them with copper braid. Done! _______________________________________________ geda-user mailing list [email protected] http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
