Eeyore said:
Why are you applying a negative voltage here ?
That's what Vss normally is.
Graham
Hey Graham,
Well, I was under the impression (maybe not correctly so, now that I look at
it again) that Vss *was* -5V. Here follows the answer to a post I made
earlier this year about the nature of Vss...
Not sure what to say. My "signal" (on the Ain/out and the A1/A0 etc.of
the
4053) is actually analog (thus my concerns about Ron), and the 74HC4053
(according to that datasheet) requires both a +5V (Vdd) and a -5V (Vee).
And (BTW) what is Vss?
Vss is the negative logic supply rail. The control logic
operates between Vss and Vdd. The analog signals can swing
between Vee and Vcc, though Vee can be connected to Vss if
the analog signals stay between the logic rails. But
reducing the total difference between Vdd and Vee from 10
volts to 5 volts almost doubles the switch on resistance
(from something like 4o ohms to something like 70 ohms).
Sooo, I guess it could be ground, but it could also be -5V? (The basic
circuit did work when I hooked it up that way...) I guess that, if I am
correct, it might even operate better in some instances, judging from the
answer given above.
So, with the 74HC4053 I use -5V for Vss, and for the 4049 I use ground for
Vss? Somebody help me here (John?) I feel I ought to be consistant, at
least...
Many thanks,
Dave