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slide 1010
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4 o9 r" S& o. L: W' GFor a CFB amplifier the open-loop gain is ZT and its feedback factor is 1/RF, making the loop-gain TCFB = ZT/RF. - C( N( K, ^. Z" [ x8 Q4 n
The signal bandwidth is determined by RF and not by the circuit gain.$ Z) p! W; Z* a: S+ w, r* S
The circuit gain is independently set with RS.
) U7 |2 d7 D9 s) ~( P" cThe signal bandwidth remains stable for all gain settings .
- A! Q X/ d3 U8 EEven for unity-gain operation, an RF resistor is required.
# F$ r) E3 w" f* j0 w8 PThe 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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