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slide 1010
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0 j4 k) r0 v' g7 ~For a CFB amplifier the open-loop gain is ZT and its feedback factor is 1/RF, making the loop-gain TCFB = ZT/RF.
% K. f y4 ?5 Z7 s: X4 G9 IThe signal bandwidth is determined by RF and not by the circuit gain./ U9 p( C0 h3 r. q# S) p
The circuit gain is independently set with RS.3 b8 |3 L+ X2 G1 Q2 v0 `
The signal bandwidth remains stable for all gain settings .
* t3 ]; ^. `0 K7 DEven for unity-gain operation, an RF resistor is required.$ y. F, I1 G7 D% N
The 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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