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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. ( S1 p2 B/ v+ h# [
The signal bandwidth is determined by RF and not by the circuit gain.
) a0 u( u. s, q% j" |The circuit gain is independently set with RS.0 s* y2 Z2 A T# L, X
The signal bandwidth remains stable for all gain settings .
) x9 z, G. m6 I) n N- cEven for unity-gain operation, an RF resistor is required.: [! `( k3 A: ], D O8 M
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., p4 c9 d6 D) m0 |& Z
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