A 900 MS/s 6b interleaved CMOS flash ADC

A 900 MS/s, 6 bit, 4-way, time-interleaved flash ADC is demonstrated. The 4 on-chip ADCs share a common reference string and preamplifiers to minimize the mismatch between channels. The measured SNDR is over 31 dB at 900 MHz with analog input at 1.1 MHz. The chip has been fabricated in a standard 0.25 /spl mu/m CMOS process and occupies an active area of 2.08 mm/sup 2/.