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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. ! S! }. C5 A0 K4 J: h* B9 L1 H
The signal bandwidth is determined by RF and not by the circuit gain.
% S$ o) a. b7 z2 h* ^" U2 JThe circuit gain is independently set with RS.
+ h5 ?4 n% J5 i: q6 uThe signal bandwidth remains stable for all gain settings .
' |6 Z# s% z: m" |. DEven for unity-gain operation, an RF resistor is required.
$ J# G8 o* f; k) u1 QThe 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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