Patent ID: 6496128
Filing Date: 2002-12-17
Classification: H03M

Abstract:
A sigma-delta analog-to-digital converter array, comprising:at least two sigma-delta converter stages each comprising an analog-to-digital (A/D) converter disposed in a forward path of the sigma-delta converter stage and at least one digital-to-analog (D/A) converter arranged in a feedback path of the sigma-delta converter stage; the at least two sigma-delta converter stages connected in a cascaded array such that an analog input signal to be converted into a digital output signal is applied to an input of a first sigma-delta converter stage of the at least two sigma-delta converter stages; and an analog differential signal corresponding to a difference between a digital-to-analog-converted output signal of the analog-to-digital converter of the first sigma-delta converter and an input signal to the analog-to-digital converter stage of the first sigma-delta converter stage is input to a second sigma-delta converter stage of the at least two sigma-delta converter stages; and the digital output signal corresponding to the analog input signal, wherein the digital output signal is obtained by combining the output signals of the respective analog-to-digital converters of the at least two sigma-delta converter stages; wherein the analog-to-digital converter of the first sigma-delta converter stage is a multi-bit analog-to-digital converter and the at least one digital-to-analog converter of the first sigma-delta converter stage is a multi-bit digital-to-analog converter; the analog-to-digital converter of the second sigma-delta converter stage is a multi-bit analog-to-digital converter and the at least one digital-to-analog converter of the second sigma-delta converter stage is a multi-bit digital-to-analog converter; and the sigma-delta analog-to-digital converter array is configured as a third order sigma-delta analog-to-digital converter.