On Sat, Apr 15, 2000 at 08:59:23PM -0400, der Mouse wrote:
> >>> 30->72 pin converters
> 
> >> The surface-mount ICs are 14-pin and hence have pin count enough to
> >> be address buffers (data buffers are, of course, unnecessary).
> > Databuffers are not unecessary, RAM chips give substantial capacitive
> > loading!  You have 4x the number of RAM chips compared to typical
> > 72pin SIMMs.
> 
> Yes - but each *data* line is still connected to only one chip.

But via substantially longer PCB traces. Anyway, these adapters are
not a very good idea on any system.

> >> I can trace many of the etch runs on the adapter, and it certainly
> >> looks as though the surface-mount chips are address buffers.
> > Or address decoding.
> 
> Except there's no address decoding necessary on the adapter.

Well, I wonder why they would not use standard data buffer chips instead
of logic gates (F04, F08)?

> > If worst come to worst I can maybe find you a 21066/166Mc chip.  Will
> > have to do some digging.
> 
> It'd probably cost more to get it to me than it would for me to get one
> locally. :-)  Besides, I wouldn't worry about it unless the machine

Dutch PTT is not so greedy ;-) for a small packet.

-- 
Wilko Bulte 		Powered by FreeBSD  	http://www.freebsd.org
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