I am unsure because A) I have never worked with PQFP, (or any smd) B) the data sheet ftp://ftp.scenix.com/datasheets/SX48_52.pdf does not specify. The pinout diagram just has text "52 - PIN /n PQFP" in the center with pin one shown in the UPPER left corner and the packaging spec shows no text on the chip, does show the dot in the lower left corner but does not label pin 1. C) the prototyping adapter I'm using (PN 160-8404-07 from http://www.adapters.com )shows a dot and indicates pin one in the UPPER left corner of the PCB when the part number/copyright text on the PCB is oriented horizontally. D) it would be just my luck that after I just managed to manually solder the chip down to the adapter (0.5 mm lead spacing) despite the fact that the chip leads all extend to far over the pads on the adapter and had to be bent back to fit.... the chip would have to be desoldered and turned !!!! (%^!@#.

BTY I put together a pretty good low cost smd soldering FAQ page on my techref page at http://www.geocities.com/SiliconValley/Lab/3544/smds.htm or http://204.210.50.219/techref/default.asp (will email if anyone interested) and I have a PCL print file that produces a nice little paper label for the back of the wire wrap adapter (if anyone else is working with the 5 port SX chip and using the 180-8404-07 adapter).

James Newton, Electronic Forms Plus,
eplus1@san.rr.com 1-619-674-9736 phone 1-619-674-9763 fax