A differential analog to digital converter (ADC) comprises first and
second resistance ladder legs, first and second amplifiers, and a
plurality of comparators. Each resistance ladder leg includes two
resistances having first ends that communicate with a middle node and
second ends that communicate with a current source. The first amplifier
applies a voltage based upon a first phase of an input signal to the
middle node of the first resistance ladder leg. The second amplifier
applies a voltage based upon a second phase of the input signal to the
middle node of the second resistance ladder leg. The plurality of
comparators each has first and second inputs, wherein the first input
communicates with one of the two resistances of the first resistance
ladder leg, and the second input communicates with one of the two
resistances of the second resistance ladder leg.