20 Oct
1999
20 Oct
'99
3:40 p.m.
On Wed, 20 Oct 1999, Tony Duell wrote:
And old...
Memory says 82s129, I have the data sheet home in that 1971 signetics
data book. I was my first ttl databook!
The 82S129 was a fusible-link PROM. It was an actual device, and in
production until quite recently.
I have here the Signetics data sheet for the 25120 'Fully Encoded 9046*N
Random Access Write Only Memory'. I suspect that's the one you're
thinking of. It includes graphs of 'Bit Capacity .vs. temperature', 'Iff
.vs. Vff', 'Number of pins remaining .vs. Number of socket insertions'
and 'AQL .vs. Selling Price'... :-)
Incidentally the nominal Vff is given as 6.3V. I wonder how many
modern-day engineers would realise the significance.
Probably only those who had been exposed to transformer powered radios
and TVs. Suggests filament voltage to me.
- don
Signetics 82mumble WOM (write only memory) april first version.
Oh, she's good. She's very good. If anyone wants to get this data sheet, it's
reprinted on page 605 of the
'Student Manual for the Art of Electronics' by Thomas C Hayes and Paul
Horowitz (2nd Edition, ISBN 0-521-37709-9)
-tony