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slide 1010
2 ]" h3 g4 Z. P* Y2 M; {1 [: ]( w ]! e% h5 |" r, q
For a CFB amplifier the open-loop gain is ZT and its feedback factor is 1/RF, making the loop-gain TCFB = ZT/RF. . C4 o% ]+ K( w5 F: L3 Q9 x
The signal bandwidth is determined by RF and not by the circuit gain.
! u; c0 N, d' y/ o; B0 Q- gThe circuit gain is independently set with RS.
! j4 @: D" ?5 J; tThe signal bandwidth remains stable for all gain settings .
' S* ?2 ~( G9 H' N' _- }' b, @Even for unity-gain operation, an RF resistor is required.
5 b6 O& }8 }4 D& R6 BThe 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." A5 ^1 @8 A% g5 P
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