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slide 1010
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. V- v, v. p& CFor a CFB amplifier the open-loop gain is ZT and its feedback factor is 1/RF, making the loop-gain TCFB = ZT/RF. # Q6 B {/ G+ p
The signal bandwidth is determined by RF and not by the circuit gain.4 a+ j# M: I& Q3 L, k+ I
The circuit gain is independently set with RS.0 k' c. r4 W% a" k9 J* r9 R* o
The signal bandwidth remains stable for all gain settings .
2 f* v. q" n$ lEven for unity-gain operation, an RF resistor is required.
; S. S# ?0 D& wThe 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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