opamp always saturate, help

MikeML

Joined Oct 2, 2009
5,444
I see no saturation. U1 swings from +1.5V to -1.5V.

U2 is sitting at 0V

The emitter follower is following... (It wouldn't if it had a load because it is not biased right).
 

Thread Starter

Santa klaus

Joined Nov 16, 2014
32
Could you check the output current. it should be sine wave (maybe with crossover distortion), i currently get a square signal.
Also, can i leave the follower biased this way?
 
Last edited:

MikeML

Joined Oct 2, 2009
5,444
Could you check the output current. it should be sinusoidal (maybe with crossover distortion), i currently get a square signal.
Also, can i leave the follower biased this way?
Are you asking about the audio.asc file you posted, or something else?
 

crutschow

Joined Mar 14, 2008
25,419
Your audio.asc circuit has only a passing resemblance to the circuit you referenced.
Why don't you simulate the referenced circuit?
 

crutschow

Joined Mar 14, 2008
25,419
U2 has no input resistor so it is acting as a comparator. Add a 2kΩ resistor in series with the output of U1.
If you look at the referenced circuit, it uses a pot for R2 which provides the resistance you are missing.
 

Thread Starter

Santa klaus

Joined Nov 16, 2014
32
Awesome, it solves the problem . I have an amplified sine wave but there some little deformation around 0
U2 has no input resistor so it is acting as a comparator. Add a 2kΩ resistor in series with the output of U1.
If you look at the referenced circuit, it uses a pot for R2 which provides the resistance you are missing.
, it
 
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