INA134, balanced an unbalanced, normal phase and inverted phase

[CJ900RR]

I want to be able to invert the phase of the signal on a new amplifier I'm working on, cause I want to be able to bridge 2 modules. I also want to be able to connect either a balanced source, or a unbalanced.

To make it easy I was thinking of using INA134 or similar IC. I'm just unsure if I am thinking right. I made some connection examples in the attached PDF. Would that work? I googled and searched everywhere but I didn't find any answer to my question.

Please help

[CharlieLaub]

Originally Posted by CJ900RR

I want to be able to invert the phase of the signal on a new amplifier I'm working on, cause I want to be able to bridge 2 modules. I also want to be able to connect either a balanced source, or a unbalanced.

To make it easy I was thinking of using INA134 or similar IC. I'm just unsure if I am thinking right. I made some connection examples in the attached PDF. Would that work? I googled and searched everywhere but I didn't find any answer to my question.

Please help

You could use the INA134 to convert the balanced to unbalanced, and then have a selector switch to choose between that and the unbalanced input, or you could just sum them at in inverting amplifier input's virtual ground.

From there you can use the DRV134 IC or similar to create your "bridging" outputs. This will take the unbalanced signal that you will have from the input stage and convert it to two 180 degree out of phase signals.

Note that you can't just use balanced input signals for amp bridging since these days it is common to have the cold pin at ground potential and not out of phase with the hot pin. Since this may be the case, it's a good idea to create the out of phase signals explicitly with the DRV134 (or similar) IC. You can also do all of this with op amps, but this will require more components and very well matched resistors to even get close to the performance of the IC version.

-Charlie