Harmonic distortion correction for 8-bit delay line ADC using gray code

Hsun-Cheng Lee, Jacob A. Abraham
2014 2014 15th Latin American Test Workshop - LATW  
Harmonic distortion correction (HDC) is an effective digital calibration technique to estimate and correct errors and distortions in an analog circuit. However, the convergence time is still a concern. In this paper, we propose the injection of a periodic 3-bit gray code sequence for HDC to digitally calibrate an 8-bit delay line ADC. In our simulation results, digital calibration with the gray code injection improves SNDR and SFDR to 42.5 dB and 45.4 dB, respectively, compared with the
more » ... ed with the original SNDR of 25.6 dB and the original SFDR of 25.7 dB, with a 13.5 milliseconds calibration time, which is 64X faster than with injection of pseudorandom numbers (860 milliseconds). Also the SNDR converges to 41.6 dB after averaging 2 24 samples, while the SNDR with injection of pseudorandom numbers converges to 41.5 dB after 2 37 samples.
doi:10.1109/latw.2014.6841928 dblp:conf/latw/LeeA14 fatcat:aaiw6tmdtzhcxcr566g7lom6cq