First and second complementary voltage signals are operatively coupled
across a series circuit comprising first and second sense resistors and a
circuit element therebetween. An output signal responsive to the
self-impedance of the circuit element is generated responsive at least
one of a voltage across the first sense resistor and a voltage across the
second sense resistor, and at least one of the first and second
complementary voltage signals is controlled responsive to the output
signal so as to provide for attenuating at least one noise signal having
a frequency that is substantially different from a frequency of the first
and second complementary voltage signals.