VFB与CFB比较2 MT-058
TUTORIAL
Effects of Feedback Capacitance on VFB and CFB Op Amps
It is quite common to use a capacitor in the feedback loop of a VFB op amp, to shape the
frequency response as in a simple single-pole lowpass filter shown in Figure 1 below. The
resulting noise gain is plotted on a Bode plot to analyze stability and phase margin. Stability of
the system is determined by the net slope of the noise gain and the open-loop gain where they
intersect.
R1 C2
A R2
……
