20 Aug
2015
20 Aug
'15
7:49 p.m.
On Aug 20, 2015, at 3:40 PM, Eric Smith <spacewar
at gmail.com> wrote:
On Thu, Aug 20, 2015 at 10:54 AM, Paul Koning <paulkoning at comcast.net> wrote:
Ok, clearly my memory was faulty. Thanks for the corrections.
paul
Ok, but when you refer to "drive
strength" I assumed you were talking about current, not voltage. By that measure
totem pole outputs are pretty much symmetrical.
Not for true (bipolar) TTL. See the specs for the 7400, 74LS00, 74S00:
http://www.ti.com/lit/ds/symlink/sn74ls00.pdf
Ioh(max) Iol(max)
7400 -0.4 16
74LS00 -0.4 8
74S00 -1 20
CMOS for comparison:
http://www.ti.com/lit/ds/symlink/sn74hct00.pdf
http://www.ti.com/lit/ds/symlink/sn74act00.pdf
Ioh(max) Iol(max)
74HCT00 -4 4
74ACT00 -24 24