does 2520 behave ok in single rail apps?

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this is the buffer for one channel only, the transformer should be 1:2 ratio for a standard charge of 10K.
The opamps can be several, for example: OPA604, OPA134, AD711 and others. 
This buffer has a gain from 12dB to 40dB. Tell me the

But I suspect that you want a buffer with volume so I will upgrade the schematic.
 

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Hi Pier,


  many thanks for that! I have a couple of questions, if you don't mind . . . . first of all, does this schematic also apply to 2520? secondly, what does the diode in parallel with R1 do?


    Many thanks,


      ANdyP
 
strangeandbouncy said:
Hi Pier,


   many thanks for that! I have a couple of questions, if you don't mind . . . . first of all, does this schematic also apply to 2520? secondly, what does the diode in parallel with R1 do?


    Many thanks,


      ANdyP

Yes you can apply a 2520.

the diode discharges the 470uF cap when the power supply turn off, It's necessary since the divider resistors are a bit high. With very lower divider resistors' values isn't necessary putting this diode because these resistors can discharge the cap in a few time without the diode, compatibly with the turn off time of the power supply.

 
the other two caps of 220uF are together discharged from opamp using the NFB network resistors, infact
these caps have circa the same voltage of the opamp pos input, and for the NFB network's action the opamp tends to maintain equal among them these three voltages: opamp's positive input and 220uF caps voltages. Since opamp's positive input voltage value is quasi-equal to 470uF cap voltage value, if this voltage change then will change the other three voltages , so when the 470uF cap is  discharged the other two caps are discharged toghether with it.  
 
strangeandbouncy said:
HI,



   thank you for that explanation! I thank you most kindly once again! You are very kind indeed.


      Best regards,


   
     ANdyP

I've just sent you by email the complete schematic of a channel (5534 opamp + out transformer).

Pier Paolo
 
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