Patent ID: 7403149
Filing Date: 2008-07-22
Classification: H03M

Abstract:
1. A folding and interpolating analog-to-digital converter (ADC), comprising: a preamp unit configured to receive an analog input signal and reference voltages having a predetermined voltage interval and to generate therefrom an equal number of reference signals, each of the reference signals having zero-crossing characteristics at a respective reference voltage; a first folding stage configured to receive the reference signals and to generate therefrom first folding signals, configured to interpolate the reference signals using both active interpolation and resistor interpolation and to generate therefrom second folding signals, and configured to generate a first group of folding signals having zero-crossing characteristics based on the first and second folding signals, wherein each folding signal in the first group of folding signals crosses a zero point at a voltage level of a reference voltage of a corresponding reference signal; a second folding stage configured to receive the folding signals in the first group of folding signals and to generate therefrom third folding signals, configured to interpolate the folding signals in the first group of folding signals using both active interpolation and resistor interpolation and to generate therefrom fourth folding signals, and configured to generate a second group of folding signals based on the third and fourth folding signals; a comparison unit configured to generate a digital code based on the second group of folding signals; and an encoder configured to encode the digital code.