A 14b 1GS/s DAC with SFDR > 80 dBc across the whole nyquist band by mixed total 3-dimesional sort-and-combine and dynamic element matching

摘要

This paper presents a 14 bit 1GS/s current-steering DAC with a mixed dynamic element matching (DEM) and total 3-dimensional sort-and-combine (T3D-SC) method. By measuring total MSB weight cells and sort-and-combining to calibrate the large static error and dynamic error which contain delay error and duty cycle error, the T3D-SC method uses digital calibration technology achieving a quiet good SFDR in wide frequency range. By using DEM method in middle bits to handle the error in middle bits, the DEM method can improve SFDR, especially in low frequency. The T3D-SC DAC is modeling in TSMC 0.18 um tech to achieve more than 20dB SFDR improve by using T3D-SC and DEM method.