A 40-mW 7-bit 2.2-GS/s time-interleaved subranging ADC for low-power gigabit wireless communications in 65-nm CMOS

A 7-bit, 2.2-GS/s time-interleaved subranging CMOS ADC for low-power gigabit wireless communication system-on-a-chip (SoC) is presented. A novel time-splitting subranging architecture is invented to significantly boost the speed of individual ADC channels. In addition, a low-power and fast-settling distributed resistor array for reference voltages is proposed to mitigate mismatches within channels. The prototype is implemented in 65 nm CMOS, occupying only 0.3 mm² chip area and consumes 40 mW at 2.2 GS/s from a 1 V supply. Measured SNDR and SFDR are 38 dB and 46 dB, respectively, with a 1.08 GHz input at 2.2 GS/s sampling rate.