I have a common mic preamp scheme based on ina217. Balanced part works, but I would want to add hi-z input (ub_buf), with gain control still done via ina217. ub_buf point is a buffered unbalanced input.
Can I just connect unbalanced input (ub_buf) to point (A) or point (B) directly?
I think I can't because in that case one of the ina217 input wouldn't be referenced to any particular level.
Is there a relatively simple way to connect unbalanced input, without permanently grounding one of the ina217 inputs, and without adding unbalanced-to-balanced block?
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