Interleaved data weighted averaging technique for speed/power relaxation in multi-bit DACs

Multi-bit delta-sigma (????) modulators suffer from the nonlinearity of feedback digital-analogue converters (DACs) caused by component mismatch. Traditional dynamic element matching techniques are limited in speed owing to the feedback delay. The proposed interleaved data weighted averaging (I-DWA) technique relaxes this speed requirement and therefore allows either a higher bandwidth or improved resolution at less power. Using the novel I-DWA technique, sampling frequencies up to 1 GHz and above become well in reach in 90 nm CMOS technology.