A 12-bit 180 MS/s Current-steering DAC with Cascaded Local-element Matching Topologies

This paper proposes a 12-bit 180 MS/s current-steering digital-to-analog converter (DAC) with cascaded local-element matching (C-LEM) schemes to significantly reduce the required number of current cells in the DAC to 28, a reduction of 99.32 % compared to the amount of required in the conventional 12-bit full thermometer-coded switching techniques. The bias circuits in the DAC use simple source follower-based level shifters to obtain the required bias voltages, simplifying the circuit configuration considerably. The prototype DAC shows the measured differential non-linearity (DNL) and integral non-linearity (INL) within 0.50 LSB and 0.78 LSB, respectively. The DAC achieves a peak spurious-free-dynamic range (SFDR) of 65.33 dB at 180 MS/s. The output current and total power of the prototype DAC are 10 mA and 38.2 mW, with analog and digital power supplies of 3.3 V and 1.8 V, respectively.