Patent ID: 7605728

Claim:
Multi-bit digital-to-analog converter, for application in high-speed and high-resolution analog-to-digital converters, comprising a number of digital-to-analog converter cells (DAC cells) and a calibration circuit to calibrate these DAC cells, characterized in that, apart from the number of DAC cells applied in the multi-bit DAC for conversion, an additional DAC cell is provided, which can be interchanged with each of the other DAC cells, and switching means to switch each DAC cell successively from the multi-bit DAC into the calibration circuit to calibrate said DAC cell without interrupting the conversion; characterized in that the calibration circuit with a DAC cell incorporated therein comprises a 1-bit analog-to-digital converter supplying a feedback signal for controlling switches in the DAC cell, a combination circuit for combining the output signal of the DAC cell with a reference value, whereafter the combined signal is fed to the 1-bit analog-to-digital converter via a loop filter.