On Thu, Aug 20, 2015 at 10:54 AM, Paul Koning <paulkon...@comcast.net> wrote:
> 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
