A 12-GS/s 81-mW 5-bit Time-Interleaved Flash ADC With Background Timing Skew Calibration

作者：El Chammas Manar^*; Murmann Boris

来源：IEEE Journal of Solid-State Circuits, 2011, 46(4): 838-847.

DOI：10.1109/JSSC.2011.2108125

• A/D conversion
• calibration
• flash ADCs
• time-interleaving

This paper presents a 12-GS/s 5-bit time-interleaved flash ADC realized in 65-nm CMOS. To improve the dynamic performance at high input frequencies, a statistics-based background calibration scheme for timing skew is employed. The timing skew is detected in the digital domain through a correlation-based algorithm and minimized by adjusting digitally controlled delay lines. In order to minimize power consumption, we employ near minimum size comparators, whose offset is reduced through foreground calibrated trim-DAC circuitry. With the timing calibration activated, the skew-related impairments are reduced by 12 dB at high input frequencies, resulting in an SNDR of 25.1 dB near Nyquist. The prototype IC consumes 81 mW from a 1.1 V supply, yielding a figure-of-merit of 0.35 pJ/conversion-step at low input frequencies, and 0.46 pJ/conversion-step for inputs near Nyquist.

• 出版日期2011-4