> For me, the vast majority of components are hard metric 
> specified! I do
> a lot of fine pitch SMD.

True!
Most *modern* packages are metric
Examples: 
MQFP-144 (ST10F168) 0.65mm pitch
FP-64A (Hitachi H8/3644, NEC 78F0034) 0.8mm pitch
QFP14-80 (Epson SED1375) 0.5mm pitch
TSOP-48 (AMD 29F400 Flash) 0.5mm pitch
Most BGAs have metric pitch

The finer the pitch of a package is, the more likely its specification
is metric. The problem is that the rounding errors are also getting
more critical with finer pitch :-(


> As has been noted before on this forum, if Protel had a hard metric
> base unit in the database it could still provide imperial 
> entry for those
> that live in backward countries :-) but with the significant advantage
> that there would be no conversion error when converting 
> between display
> units.

That is because
  1 inch is *exactly* 25,4 mm
whereas
  1 mm is *roundabout* 0,0393700787401574803149606299212598 inches
;-)

> Protel's use of english base units is a fundamental flaw that 
> could easily
> have been rectified in the process of writing a major new 
> release (e.g. in
> Protel 98 or in DXP), and it would have been easy to specify 
> that version 5
> databases are hard metric, while versions below this are 
> english base units.
> The fact that it wasn't was, for me, the biggest 
> disappointment with DXP.


Well spoken.


Cheers,
Ralf

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