摘要 |
A notch filter circuit is provided including a first stage circuit and a second stage circuit. The first stage circuit sums a filter input signal with a filter output signal to form a summation signal. The second stage circuit includes a first tee network and a second tee network. The first tee network low-pass filters the filter input signal to form a first tee output signal. The second tee network high-pass filters the summation signal to form a second tee output signal. A first multiplying digital-to-analog converter is electrically coupled to the first tee network and the second tee network. The first converter modifies the gain of the second tee network in response to a gain signal to form a corrected second tee network signal, thereby adjusting a notch filter frequency.
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