AnsweredAssumed Answered

Audio Balanced Line Driver

Question asked by three21mark on Aug 31, 2012
Latest reply on Sep 20, 2012 by rezam

   I need a balance driver circuit for an audio type application. I also want to the circuit to be able to drive cable capacitance while maintaining a low output impedance.  I found this circuit (redrawn below) in the Analog Devices OP AMP Applications book.

 

In_the_Loop.png

My question is can I use this circuit in the unit gain mode as shown below to make a balanced driver.  The circuit uses and inverting and non-inverting amplifier, both with a gain of one as shown below. I do want to roll off the response at high frequencies and that can be done with C2 on the inverting stage.  My thought is that I could set R1 and C1 on the non-inverting stage to match the roll-off of inverting stage.

 

Diff_In_the_Loop.png

Outcomes