At 08:26 PM 5/22/2005 -0400, you wrote:
>On the MicroChip data sheet for the 16F876A there is an outline drawing of
>the pin numbering scheme for the QFN version of the chip. It shows the
>numbers running counter-clockwise. On other drawings of the QFN-28 package
>(not MicroChip) the numbers run in a clock-wise manner. None of my drawings
>state which side (top or bottom) they show. I am at a loss to know which is
>correct.
>
>Any enlightenment will be appreciated.
>
>TIA
>
>Vic

The mechanical drawing of the part (DS39582B-page 218) clearly shows the 
pin numbers
running CCW from the top, same as the outline drawing (and same as Atmel's
QFN-28 and National's CSP-28). More drawings here:

http://ww1.microchip.com/downloads/en/PackagingSpec/00049AC.pdf

Remember that if the mechanical drawing shows features that are only visible
from one side (and they are not dashed) then that is the side it is showing.
Their drawings are neither conventional first-angle (Euro & Asia) or
third-angle (US) orthographic projections, BTW.

Best regards,

Spehro Pefhany --"it's the network..."            "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com
-->Inexpensive test equipment & parts http://search.ebay.com/_W0QQsassZspeff



-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist