Patent ID: 7015850

Claim:
A sampling circuit to sample a source signal received on an input path, a noise signal of high frequency components also being received on said input path, said sampling circuit comprising: a first circuit portion receiving an input signal on said input path, said input signal containing both of said source signal and said noise signal, said first circuit portion generating an output signal by limiting bandwidth of said input signal, wherein said noise signal being substantially absent in said output signal due to said limiting; and a second circuit portion sampling said output signal generated by said first circuit portion, wherein said first circuit portion comprises a low pass filter, wherein said second circuit portion is implemented as a switched capacitor circuit, wherein said low pass filter comprises: a resistor receiving said source signal on one terminal and other terminal of said resistor being connected to a first node; and a first capacitor connected between said first node and a second node, wherein said first circuit portion further comprises: a first switch connected between said second node and a common mode voltage; and a second switch connected across said first capacitor, and wherein said second circuit portion comprises: a buffer being coupled to receive an input from said first node; a second capacitor connected between a third node and a fourth node; a third switch connected between an output of said buffer and said third node; and a fourth switch connected between said fourth node and said common mode voltage.