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slide 1010
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For a CFB amplifier the open-loop gain is ZT and its feedback factor is 1/RF, making the loop-gain TCFB = ZT/RF. * y i# Y. a7 J- c4 x3 n: ~
The signal bandwidth is determined by RF and not by the circuit gain.
9 J2 k; ?: ~$ ^' uThe circuit gain is independently set with RS.& j2 m8 j+ q" d' T9 O
The signal bandwidth remains stable for all gain settings .
$ c k( K4 f8 \- s- `8 @9 gEven for unity-gain operation, an RF resistor is required.
! m+ T, S. c% h l& ZThe best practice when designing with CFB op-amps is to use the RF values given in the datasheet and to adjust the desired gain level through RS.
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