Re: what is Vmeas

Hello Nick:

On Fri, 06 Mar 1998 12:16:13 PST you wrote

> Hi Ibis Gurus,
>
> Could anybody expalain me what is Vmeas.
>
 <snip a lot of stuff>
>
>

   Well, the best way I can explain it is thru example. Suppose you're
measuring
the propagation delay thru a simple gate, as shown in the example below:

                 __________________________________________
                /
   input /
  ____________/|
               |
               |
               |
   ____________|_______________________ |
               | \|
  output | \-- Vmes
               | |\_____________________________

               | |
               | |
               |<------- Tpd --------->|

  The propagation delay (Tpd) is measured from a specific point on the input
waveform,
to when the output waveform crosses a specific voltage. This voltage is
referred
to a 'Vmes' (or measurement voltage). For CMOS and TTL logic Vmeas is
generally 1.5v.
Knowing Vmeas is important because CAE tools that perform system timing
calculations
use this value to determine how to derate device propagation delay due to
interconnect. I hope this helps.

              Regards,
              Stephen Peters
              Intel Corp.

 
Received on Tue Mar 10 13:04:34 1998