A buffer for the input to an A/D converter operates in two stages. During the first stage, the input is not provided directly to the A/D converter; rather, a buffered output which corresponds to the input is provided to the A/D converter so as to pre-charge the sampling capacitor of the A/D converter to a value that is substantially close to the input. In the second stage, the input is provided directly to the A/D converter, which charges its sampling capacitor to the value of the input. Because the sampling capacitor is pre-charged to a value that is substantially close to the input, and because the sampling capacitor is charged to this value through a buffer, reflections back into the input which otherwise might have been caused by a difference between the value stored on the sampling capacitor and the input are largely avoided.
CROSS-REFERENCE TO RELATED APPLICATION
This application claims the benefit of U.S. Provisional Patent Application No. 60/822,150, filed Aug. 11, 2006, the contents of which are hereby incorporated by reference as if fully stated herein.