Patent ID: 9209829
Filing Date: 2015-12-08
Classification: H03M

Abstract:
1. An apparatus for converting a continuous-time, continuously variable signal into a sampled and quantized signal, comprising: an input line for accepting an input signal that is continuous in time and continuously variable; a continuous-time quantization-noise-shaping circuit; a sampling/quantization circuit coupled to an output of the continuous-time quantization-noise-shaping circuit; and a line coupling the output of the sampling/quantization circuit back into the continuous-time quantization-noise-shaping circuit, wherein the continuous-time quantization-noise-shaping circuit comprises an adder that includes a plurality of inputs and an output, with the input signal being coupled to one of the inputs of the adder, the output of the adder being coupled to one of the inputs of the adder through a first filter, the output of the sampling/quantization circuit being coupled to one of the inputs of the adder through a second filter, wherein the overall responses of the first filter and the second filter include a lowpass component, and wherein the continuous-time quantization-noise-shaping circuit has a noise transfer function with a minimum at a particular frequency.