11 Aug
2006
11 Aug
'06
11 p.m.
On 8/12/06, woodelf <bfranchuk at jetnet.ab.ca> wrote:
Still I would like to see in surface mount ---
tiny Flip/Clips and see how small you can build
a PDP-{Favorate number}.
I _have_ thought about that for replacement -8/L and -8/i boards -
design a simple board with, say, 4 to 6 16-pin SO pads and decoupling
caps and a dual row of jumper pads to cross-connect the edge fingers
to the various chip pads to be able to replicate, say, an M111 vs an
M117. The "problem" is that I doubt you could get real TTL (not
LS-TTL) parts in SO. I haven't experimented with replacing TTL with
LS parts in any of my -8s, so I don't know if there would be any
issues or not. So far, I've always had enough of the right things on
hand when I go to replace a chip on an M-series module. I would think
that the dimensions could be on the order of 2 x the size of just the
area of the fingers.
The advantage, of course, is that it would be easy to make a large
number of these on one PCB panel, reducing per-unit costs. Using one
(or maybe two at most) base designs would also help quantity issues.
You could sit down one day and make a stack of a dozen M111s, then
make two dozen M113s the next day with the same PCB; just add the
right SO-parts and configure the jumpers in the right order, and there
you are.
-ethan