摘要 |
The present invention provides an active low-pass filter system including a low-pass filter circuit and at least one frequency-rejecting network coupled to the low-pass filter circuit. The frequency-rejecting network is included in a resistive forward signal flow branch of the low-pass filter. The present invention also provides a power amplifier system for driving a load. The power amplifier system includes a pulse width modulation circuit which creates ripple spectra, an error amplifier and modulator circuit, and a demodulation filter connected in series, and a feedback control loop coupled to the pulse modulation circuit and including an active low-pass filter having a feedback demodulation filter and an isolated-integrator frequency-rejecting network. |