Patent ID: 8217819
Filing Date: 2012-07-10
Classification: H03M

Abstract:
1. A multiplying digital-to-analog converter (MDAC), comprising: an amplifier having an inverting input node, a non-inverting input node and an output node providing an output signal; a plurality of capacitors, first ends of the plurality of capacitors being electrically coupled to the inverting input node, wherein two of the plurality of capacitors are alternatively configured as a feedback capacitor across the inverting input node and the output node, wherein each of the plurality of capacitors is composed of at least two sub-capacitors; a plurality of sampling switches, through which second ends of the plurality of capacitors are electrically coupled to an input signal, wherein the plurality of sampling switches are closed during a sampling period; a plurality of amplifying switches, through which the second ends of the plurality of capacitors are electrically coupled to a plurality of DAC voltages respectively; and a sorting circuit configured to sort the sub-capacitors, wherein the sorted sub-capacitors are then paired in a manner such that variance of mismatch among the sub-capacitors is thus averaged.