Patent ID: 6552592
Filing Date: 2003-04-22
Classification: H03M

Abstract:
A differential input circuit for a digital signal processing system, said differential input circuit comprising:a low pass filter that receives a compensated differential input signal, and provides a filtered differential input signal; an analog-to-digital converter that receives said filtered differential input signal, and provides a digitized signal indicative of the difference between inverting and non-inverting signal components of said filtered differential input signal; an evaluation unit that receives said digitized signal, and compares said digitized signal against a threshold value, and provides an output signal indicative of the difference between said digitized signal and said predetermined threshold value; and means, responsive to said output signal and an analog differential input signal having analog inverting and non-inverting signal components, for adjusting the voltage difference between said analog inverting and non-inverting signal components in response to said output signal using a plurality of switched current sources, to provide said compensated differential input signal.