[gta02-core] More symbols - FA2012, RT9711 and DTC123

Werner Almesberger werner at openmoko.org
Sat Jun 13 05:57:14 CEST 2009


Rene Harder wrote:
> Well, for the most IC packages (SOP, TSOP, QFN etc.) i agree but I've
> seen so many different variations in the pin numbering of SOT packages i
> really can't tell what is "the standard" for transistors.

Hmm, I haven't seen too much variation for the actual numbers.
How B, C, and E are assigned to the pins is a different story,
though ...

> Why clockwise? I would go for counter-clockwise (pin 1 bottom, left),
> thats what ON, NXP and Diode is using, so 3:1. ;-)

Argh. I hate those single-bit data corruptions. Yes, that's what
I meant.

> Rohm recommends a pad size of 0.6x0.7 (mm) for the EMT3 package compared
> to ON 0.356 x 0.508 (mm) SOT416. Thats quite a difference although the
> pitch and actual pin size is almost identical.

Oh joy. Openmoko used even smaller copper areas of only 0.6 x 0.3
and 0.6 x 0.2 mm:

http://people.openmoko.org/werner/dtc123.png

So I guess we should be fine with one of the regular SOT-416
footprints. ON Semi use 0.508 x 0.356 mm [1], NXP are a bit
more generous with 0.6 x 0.5 mm [2].

[1] http://www.onsemi.com/pub_link/Collateral/DTC114EET1-D.PDF
[2] http://www.nxp.com/acrobat/packages/footprint/SOT416_fr.pdf

- Werner



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