Patent ID: 10840891

Abstract:
An apparatus performs interpolation/decimation in a digital circuit that receives an input signal and includes upsampling/downsampling and filtering stages. First and second paths include distinct first and second portions of the upsampling/downsampling and filtering stages. The first path consumes less quiescent state power. A selection circuit uses the first or second path and turns off the unused first or second path based on input signal spectral content or level. A mode includes applying a front-end digital/analog gain and a corresponding back-end analog/digital attenuation in conjunction with the first path being used and the second path being turned off. A cross-fader uses the first and second paths in a weighted mix manner while making a transition between using the first and second paths. The second path has higher filtering performance (e.g., superior stopband attenuation, passband ripple, transition band, e.g., via higher order or greater bit-width filtering).