Hi. I wonder if anyone can help me to understand this issue:
So I was testing the Non Inverting PWM and the Inverting PWM for this op amp. I'm generating a triangle wave with 10Vpp and F=100hz
CIRCUIT:
For the Inverting: I calculated and manually plotted the graph of Vo VS t, and then I simulated with Proteus to check if I was correct, and indeed I was.
For the Non inverting: I also plotted this graph, and the results I had where theses ones:
When the AC signal reaches 3v and 5v, then Vo=5v, which means TH= 3ms. But when I simulated for the Non Inverting input, I've got a different graph:
As you can see, it happens that the values for Vo are inverted, and Vo is HIGH when the triangle wave reaches negative values of -2 and -5, the signal stays in HIGH 3ms, but the values for Vo are not the same and according to this statement where:
Ed= V+ (-) V- If Ed's positive then Vo=HIGH, if Ed's negative then Vo=LOW
Then according to that:
(1) Ed = -5-3 = -8 LOW
(2) Ed = -4-3= -7 LOW
(3) Ed = -3-3= -6 LOW
(4) Ed = -2-3= -5 LOW
(5) Ed = -1-3= -4 LOW
(6) Ed = 0-3= -3 LOW
(7) Ed = 1-3= -2 LOW
(8) Ed = 2-3 = -1 LOW
(9) Ed = 3-3 = 0 LOW
(10) Ed = 4-3 = 1 HIGH
(11) Ed = 5-3 = 1 HIGH
Vo should be LOW for all those values except for (10) and (11), right?
If I'm wrong, then what could be I missing? I've been reading about this but can't find a clear answer.
If somebody can help me, I'll be extremely grateful!
So I was testing the Non Inverting PWM and the Inverting PWM for this op amp. I'm generating a triangle wave with 10Vpp and F=100hz
CIRCUIT:
For the Inverting: I calculated and manually plotted the graph of Vo VS t, and then I simulated with Proteus to check if I was correct, and indeed I was.
For the Non inverting: I also plotted this graph, and the results I had where theses ones:
When the AC signal reaches 3v and 5v, then Vo=5v, which means TH= 3ms. But when I simulated for the Non Inverting input, I've got a different graph:
As you can see, it happens that the values for Vo are inverted, and Vo is HIGH when the triangle wave reaches negative values of -2 and -5, the signal stays in HIGH 3ms, but the values for Vo are not the same and according to this statement where:
Ed= V+ (-) V- If Ed's positive then Vo=HIGH, if Ed's negative then Vo=LOW
Then according to that:
(1) Ed = -5-3 = -8 LOW
(2) Ed = -4-3= -7 LOW
(3) Ed = -3-3= -6 LOW
(4) Ed = -2-3= -5 LOW
(5) Ed = -1-3= -4 LOW
(6) Ed = 0-3= -3 LOW
(7) Ed = 1-3= -2 LOW
(8) Ed = 2-3 = -1 LOW
(9) Ed = 3-3 = 0 LOW
(10) Ed = 4-3 = 1 HIGH
(11) Ed = 5-3 = 1 HIGH
Vo should be LOW for all those values except for (10) and (11), right?
If I'm wrong, then what could be I missing? I've been reading about this but can't find a clear answer.
If somebody can help me, I'll be extremely grateful!