On Apr 12, 2013, at 8:22 AM, "Shoppa, Tim" <tshoppa at wmata.com> wrote:
At the flip chip level it would include definitions
for DEC3639B (aka 2N3639), D662 (aka 1N645) and D664 (aka 1N3606). Pretty standard stuff
to read the datasheets and make SPICE models.
A real design (or redesign) would pay extensive attention to margining just like the
original designers did. SPICE can help verify to an extent, but all the details you
actually need for design of RTL/DTL/flip-flop are in the 60's TI transistor design
books.
Yeah, I can't stress enough that SPICE is NOT A DESIGN TOOL.
It is a verification tool. People coming out of college in
my generation fail to understand that because even a cheap
PC runs complex SPICE simulations in a fraction of the time
that the original machines did... that, and they're lazy.
The late, great Bob Pease was fond of pointing out that both
SPICE and spreadsheets are great at giving you the answer
you want, not the answer you need (the right one).
- Dave