Patent ID: 9088273
Filing Date: 2015-07-21
Classification: H03K

Abstract:
1. An apparatus for generating a pulse width modulation (PWM) signal using samples of an analog signal, comprising: cross point logic configured to determine which of the samples along the analog signal are adjacent to a crossing point of a reference signal with the analog signal by identifying adjacent samples of the samples between which the crossing point occurs, wherein the crossing point is a point where the analog signal intersects the reference signal, wherein the crossing point is not a zero crossing point, wherein the samples are samples of the analog signal, wherein identifying the adjacent samples includes identifying the adjacent samples by comparing the samples with the reference signal and determining when a change in polarity in values produced from the comparisons occurs; an interpolation logic configured to adaptively interpolate points between the adjacent samples along the analog signal that approach the crossing point by using the adjacent samples as a starting boundary for a region when adaptively interpolating the points, wherein the interpolation logic is configured to adaptively interpolate the points to iteratively refine the region within which the crossing point occurs; search logic configured to search within the region refined from adaptively interpolating the points to produce an estimated location of the crossing point by using the interpolated points; and a signal generator configured to generate a pulse in a pulse train of the PWM signal as a function of the estimated location of the crossing point.