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slide 1010
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2 H) ?2 d. [# N6 bFor a CFB amplifier the open-loop gain is ZT and its feedback factor is 1/RF, making the loop-gain TCFB = ZT/RF.
( ?1 W, E; Y; L4 OThe signal bandwidth is determined by RF and not by the circuit gain.$ @0 }0 G5 K9 h1 k' J! ]8 i' C1 X7 _$ W
The circuit gain is independently set with RS./ O' R! U1 b2 p/ U
The signal bandwidth remains stable for all gain settings .
% g8 Q' L4 o8 v% _3 Y% h; dEven for unity-gain operation, an RF resistor is required.
; K6 a4 M( `) H- {: C: n: K$ @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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