On Wed, 8 Feb 2006, Wouter van Ooijen wrote:

>>> I might be a sloppy reader, but I can't even find a switch-on time
>>> specification, which would be the root issue here. So
>> again, no data =>
>>> no conclusions :(
>>
>> Ton should be about 5 nsec for 1N4148.
>
> 'should' is not a valid input for design. Can you locate that parameter
> in the (any?) datasheet?

Hmm, you seem to have a point there. I can only find the trr but I infer 
that ton is also of the same order of magnitude. The best data sheet is 
from Philips, here:

http://pubpages.unh.edu/~aperkins/pdf/1N-devices/1N4148.pdf

another, showing trr/current plot (National):

http://www.aleeanne.org.uk/datasheets/datasheet2/1N914.PDF

I inferred the data from the max. recommended operating frequency 
(100MHz). I suspect that other problems come in between by the time you 
consider the 4nsec value (like lead inductance). The trr measurements 
are made with 10mm leads in FR4 board. I think that this is just 
hair-splitting here, beyond a certain point.

Peter
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