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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.
% T% w( d ~# ?The signal bandwidth is determined by RF and not by the circuit gain.. N0 A# s! X0 r# I" F
The circuit gain is independently set with RS.! m7 a' o4 t9 }
The signal bandwidth remains stable for all gain settings .
, S! b- A+ @ M9 nEven for unity-gain operation, an RF resistor is required.
* F) u) m; r% o4 n, K' DThe 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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