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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. 5 A: g# B4 @7 q, f7 t+ g9 u
The signal bandwidth is determined by RF and not by the circuit gain.6 P' ?4 a! n% |
The circuit gain is independently set with RS.
0 w0 v' y* z \$ s" K; l7 S9 |The signal bandwidth remains stable for all gain settings .
/ L8 Y, R1 W$ ^! ZEven for unity-gain operation, an RF resistor is required.
; y9 h1 k9 V: ~; E, _4 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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