Offset calibrating comparator array for 1.2-V, 6bit, 4-Gsample/s flash ADCs using 0.13/spl mu/m generic CMOS technology

A 1.2-V calibration comparator array for a flash-type ADC has been developed using 0.13/spl mu/m generic CMOS technology. The developed offset calibration technique corrects the offset mismatch better than 6bit resolution. By employing an offset calibration circuit in the comparator array, the comparator array can operate at low supply voltages. To evaluate the comparator array, a-bit flash-type ADC was fabricated that occupies 0.198 mm /sup 2/. With a 1.2-V power supply, it achieves 4.0 GSample/s and consumes 182 mW.