A 14-bit, 10-Msamples/s D/A converter using multibit ΣΔ modulation

A 14-bit digital-to-analog converter based on a fourth-order multibit sigma-delta modulator is described. The digital modulator is pipelined to minimize both its power dissipation and design complexity. The 6-bit output of this modulator is converted to analog using 64 current-steering cells that are continuously calibrated to a reference current. This converter achieves 85-dB dynamic range at 5-MHz signal bandwidth, with an oversampling ratio of 12, The chip was fabricated in a 0.5-mu m CMOS technology and operates from a single 2.5-V supply.