Didn't see any threads considering problem that I have.
I have a task of designing an amplifier with following qualities:
-inverting op-amp circuit for voltage amplifying
-a b-class push-pull circuit for current amplifying
-bandwith 20-20000Hz
-voltage gain 10
-etc.
So I managed to design a fairly good amp (well i think so, because the PSPICE simulations look quite good) using guidelines from the
B Class Audio amplifier example that can be found in this website
(http://www.allaboutcircuits.com/vol_6/chpt_6/10.html).
But the problem is, that I have to show its stability by simulating the
circuit with PSPICE and plotting the bode diagram and find its gain and phase margin. So how do I do that.
Sorry that I don't have the images of my particular design, but you can
refer to the circuit in the example above url (because its quite similar, except I'm using only one op amp and some other minor things).
If I understand correctly, the stability margins of a feedback system should be looked from the OPEN-LOOP system Bode diagram. So how do I simulate the open-loop system gain and phase of the circuit using PSPICE?
Should I just cut the feedback wire and simulate and that's it? Or I'm I totally wrong about the whole stability thing?
I have a task of designing an amplifier with following qualities:
-inverting op-amp circuit for voltage amplifying
-a b-class push-pull circuit for current amplifying
-bandwith 20-20000Hz
-voltage gain 10
-etc.
So I managed to design a fairly good amp (well i think so, because the PSPICE simulations look quite good) using guidelines from the
B Class Audio amplifier example that can be found in this website
(http://www.allaboutcircuits.com/vol_6/chpt_6/10.html).
But the problem is, that I have to show its stability by simulating the
circuit with PSPICE and plotting the bode diagram and find its gain and phase margin. So how do I do that.
Sorry that I don't have the images of my particular design, but you can
refer to the circuit in the example above url (because its quite similar, except I'm using only one op amp and some other minor things).
If I understand correctly, the stability margins of a feedback system should be looked from the OPEN-LOOP system Bode diagram. So how do I simulate the open-loop system gain and phase of the circuit using PSPICE?
Should I just cut the feedback wire and simulate and that's it? Or I'm I totally wrong about the whole stability thing?
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