Abstract
Otala's suggested rules for eliminating transient intermodulation distortion (TIMD) in a low-pass feedback amplifier have been widely and wrongly interpreted as being necessary. In fact, the necessary and sufficient condition, for avoiding gross TIMD with a broad-band input signal, is that the forward-path stages before the dominant pole should not clip on a signal input which is twice the amplitude of full rated input to the complete amplifier including feedback. When the input signal is band limited, this dipping criterion can be relaxed by a factor approximately equal to the ratio of the (signal 3 dB bandwidth) to the (amplifier closed-loop 3 dB bandwidth). In both cases the condition is essentially independent of the low-frequency loop gain. There is no TIMD penalty whatsoever in using a large amount of feedback, provided the forward-path gain is concentrated in stages that do not precede the dominant pole. All the usual benefits of feedback accrue with increasing loop gain.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
More From: IEEE Transactions on Acoustics, Speech, and Signal Processing
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.