[time-nuts] PICTIC II questions

[David]

Step recovery diodes turn off fast but have a relatively long storage
time.  The fastest switched current integrators use schottky diodes.

On Tue, 7 Feb 2012 14:06:55 +0100, Azelio Boriani
<azelio.boriani at screen.it> wrote:

>To enhance the PICTIC II performance can step recovery diodes be used?
>Maybe the fast turn off can boost the switching capabilities of the
>interpolator for best resolution...
>
>On Tue, Feb 7, 2012 at 12:35 PM, Hal Murray <hmurray at megapathdsl.net> wrote:
>
>>
>> attila at kinali.ch said:
>> > BTW: does anyone know how these days low cost FPGAs perform in terms of
>> > jitter? (the data sheets are kind of scarce in that regard). And how do
>> they
>> > compare to state of the art ECL logic?
>>
>> Generally, not good.
>>
>> The general problem is that they have a lot of logic and a lot of I/O
>> drivers
>> and shared power/ground pins.  Things are messy if you have multiple
>> clocks.
>> Things are better if you only have one clock and better if you don't have
>> any
>> nearby drivers switching at the same time.
>>
>> For a few critical signals, you could reclock in an external FF.