A 12-bit 150-MHz 1.25-mm2 CMOS DAC

Abstract

This paper presents a 12-bit 150-MHz current steering DAC with hierarchical symmetrical switching sequence that compensates gradient errors. The circuit of the DAC employs segmented architecture; the least significant bits (LSBs) steer a binary weighted array, while the most significant bits (MSBs) are thermometer decoded and steer a unary array. The measured differential nonlinearity and integral nonlinearity are ±0.6 LSB and ±0.9 LSB, respectively. The circuit is fabricated in 0.5 μm, two-poly two-metal, 5.0 V, mixed-signal CMOS process. It occupies 1.27 mm×0.96 mm chip area, when operating at 150 MHz and dissipates 91.6 mW from a 5.0 V power supply, which is much smaller.