Re: What is SSTL?

John V Fitzpatrick (John.Fitzpatrick@ln.cit.alcatel.fr)
Tue, 03 Jun 1997 09:35:25 +0200

Danwei,

I too would be very interested in finding some reading
material on SSTL, but there doesn't seem to be much about.

>From reading between lines of datasheets, my guess is that
the basics of SSTL are:

- standard push-pull CMOS outputs
- input threshold defined by an external voltage reference
(divided down Vsupply)

Because the input thresholds are tighter than TTL, it is possible
to use a combination of series and parallel terminations to
guarantee incident wave switching.

The main application appears to be memory modules. The proponents
of SSTL would have a 25ohm resistor close to the module connector
to mask the effect of the module stub.

Regards,
John

-- 
John Fitzpatrick   <John.Fitzpatrick@ln.cit.alcatel.fr>    
Alcatel Telecom, 4 rue de Broglie, 22304 Lannion, France
Tel: +33(0)2.96.04.79.33  Fax: +33(0)2.96.04.85.09

Danwei Xue wrote: > > Hello, > > Could anyone explain what is Stub Series Terminated Logic (SSTL) and > point out where I can find some reading materials on it? > > Thank you very much in advance, > > Danwei > Apple Computer, Inc.