T
Theo Markettos
- Jan 1, 1970
- 0
I was just wondering...
Roughly when were power supply decoupling capacitors first deemed necessary
in circuit design? I'm thinking mostly logic circuits here, though I can
see that audio/RF circuits might have needed them too. I suppose every DC
PSU has a smoothing capacitor doing roughly the same job but I was more
thinking about adding capacitors around the circuit to provide localised
decoupling. Were they necessary in valve (vacuum tube) circuits? If not,
in what technology did they first appear (RTL/DTL/TTL etc)? Was there any
prior use in another field (say RF) and they were later used in logic
circuit?
The earliest boards I can remember (late 70s/early 80s) seem to have them
on, but I haven't seen many earlier boards and can't say I've been looking
for them specifically...
Thanks,
Theo
Roughly when were power supply decoupling capacitors first deemed necessary
in circuit design? I'm thinking mostly logic circuits here, though I can
see that audio/RF circuits might have needed them too. I suppose every DC
PSU has a smoothing capacitor doing roughly the same job but I was more
thinking about adding capacitors around the circuit to provide localised
decoupling. Were they necessary in valve (vacuum tube) circuits? If not,
in what technology did they first appear (RTL/DTL/TTL etc)? Was there any
prior use in another field (say RF) and they were later used in logic
circuit?
The earliest boards I can remember (late 70s/early 80s) seem to have them
on, but I haven't seen many earlier boards and can't say I've been looking
for them specifically...
Thanks,
Theo