Look-ahead delta sigma modulator with pruning of output candidate vectors using quantization error minimization pruning techniques

摘要

A look-ahead delta sigma modulator utilizes pruning techniques to reduce the number of possible output candidate vectors used to determine quantization output values. The look-ahead delta-sigma modulators can also combine the pruning techniques with a reduction in the amount of processing by simplifying the computations used to generate quantizer output values. In one embodiment, the pruning techniques exploit application of superposition techniques to a loop filter response of the look-ahead delta sigma modulator. The set of possible pattern response vectors can be pruned to form a subset of P candidate pattern response vectors. If an element value of a pattern response vector proximally matches a value of the corresponding reference element of the natural response vector, a quantizer uses the proximally matching pattern response vector to determine a quantization output value.