FEEDBACK SYSTEM WITH IMPROVED STABILITY

摘要

Techniques for improving stability of a feedback system are described. In an exemplary design, the feedback system includes a forward path and a feedback path. The forward path receives an input signal and a rotated feedback signal and provides an output signal having a phase shift. The feedback path receives the output signal, generates a feedback signal, and rotates the feedback signal to obtain the rotated feedback signal having at least part of the phase shift removed. In another exemplary design, the feedback system includes a forward path and a feedback loop. The forward path receives a combined signal and provides an output signal having a phase shift. The feedback loop generates an error signal based on an input signal and the output signal, generates the combined signal based on the error signal and the input signal, and performs phase rotation to remove at least part of the phase shift.