QUALCOMM Incorporated
Low power high speed maximum input supply selector

Abstract:

Techniques and apparatus for selecting a maximum input supply voltage from multiple input power supplies. An example maximum input supply selection circuit includes a parallel array of comparators and selection logic to select the maximum input supply voltage, supply present detectors, comparator settling logic including a warm-up delay timer to provide for comparator settling, and comparator enable logic for disabling all comparators and entering an ultra-low power mode.