I little bit off topic but i found this for our contributors that fly in a simulator :http://www.analog.com/static/imported-files/application_notes/AN-138.pdf
What i would really like to build is the circuit you can download here. If we count a folded cascode as a one stage amplifier this can work. I have done the folded cascodes referenced to the constant current sources. That can be substituted with fixed bias.
The circuit may have some bugs but it is a starting point.
The circuit may have some bugs but it is a starting point.
The values of the RIAA are only place holders. We need a simulation to find out the right values with the gain we want. I did not try the servo, it is only an idea.
You can be sure this works fine.
The output current of the OP may not be high enough to compensate for offset
(remember Vled is a weak function of current). R15 should be zero.
Perhaps a non inverting servo is necessary here?
You may want to connect R16 to output VF3.
P3 and P4 are not required.
R4,C5 and R5 ,C* are also not required in my opinion.
The output current of the OP may not be high enough to compensate for offset
(remember Vled is a weak function of current). R15 should be zero.
Perhaps a non inverting servo is necessary here?
You may want to connect R16 to output VF3.
P3 and P4 are not required.
R4,C5 and R5 ,C* are also not required in my opinion.
MiiB, i made a new BJT buffer, just in case we would like to try something different then the current Paradise J-Fet buffer. I call it a Szikley Diamond. Circuit comes soon.
I like the buffer...... wonder what input impedance is... could have influence on the RiAA circuit.
We can mirror in the current for the input . This way we have a good injection possibility for the servo
We can mirror in the current for the input . This way we have a good injection possibility for the servo
That depends on how high the idle current is in the input stage. Other then that the input BJTs are bootstrapped on CCSs so input impedance should be high.
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