A Dynamic Dither Gain Control Technique for Multi-Level Delta-Sigma DACs with Multi-Stage Second Order Dynamic Element Matching

作者：Tamura Yu^*; Ido Toru; Taniguchi Kenji

来源：IEICE - Transactions on Electronics, 2011, E94C(3): 346-352.

DOI：10.1587/transele.E94.C.346

• dynamic element matching
• dither control
• delta-sigma digital-to-analog converter

A dynamic dither gain control technique for multi-level delta-sigma Digital-to-Analog Converters (DACs) using multi-stage Dynamic Element Matching (DEM) with a second order loop filter is proposed. The proposed technique provides improvement on the mismatch shaping performance through dynamic control of delta-sigma modulator dither gain. A large dither gain, which suppresses DEM operation dependency on input signal, is applied to delta-sigma modulator, when DEM loop filter output is greater than a designed reference. The design example using the proposed technique on a third order 17-level delta-sigma modulator with 3-stage cascaded DEM is shown in this paper. Simulation result with 1% analog segment mismatch shows over 10 dB improvement of THD+N performance under -50 dB amplitude input signal, compared to the case without the proposed technique.

• 出版日期2011-3