[time-nuts] Metastability (was Brooks Shera)

[David McGaw]

S/LS logic was introduced in the mid 70's, F/AS/ALS around 1980, HC was 
early 80's.  By the third 7400 generation (F/AS/ALS) the problem was 
well known with parameters available and the logic fairly hard to it.


On 3/25/13 2:56 PM, Attila Kinali wrote:
> On Mon, 25 Mar 2013 14:03:23 -0400
> David McGaw <n1hac at alum.dartmouth.org> wrote:
>
>> Actually, most modern FFs are hardened against metastability so often a
>> single synchronizer will do especially if it is feeding a synchronous
>> circuit.
> I would not count on that. Most 74xx that hobbyists use are from
> the HC and HCT families. These have been designed in the 70s (IIRC)
> and i very much doubt that any of the manufacturers changed anything
> in their design since then.
>
> 			Attila Kinali
>