A Low-Power 9-Bit 222 MS/s Asynchronous SAR ADC in 65 nm CMOS
This paper presents a 9-bit 222 MS/s low-power asynchronous single-bit/cycle successive approximation register (SAR) ADC. The SAR ADC combines techniques such as asynchronous clocking, binary-weighted custom-designed capacitive DAC with small unit capacitors, splitting monotonic capacitor switching, and dynamic SAR memory to optimize both power consumption and SAR loop delay using a single comparator. Measurement results show that the 9-bit SAR ADC achieves 47.6 dB SNDR and 29.6 fJ/conversion-step figure-of-merit (FoM) near Nyquist frequency at 222 MS/s, consuming 1.07 mA from a 1.2 V supply. The ADC does not consume static power and the current consumption scales down linearly with the sampling rate, keeping the low FoM value constant over a very wide sampling frequency range. The design occupies an active area of 92 μm × 180 μm (0.017 mm 2 ) in 65 nm CMOS.
WOS:000706854700124
2020
978-1-728133-20-1
New York
IEEE International Symposium on Circuits and Systems
1
5
REVIEWED
Event name | Event place | Event date |
Sevilla, Spain | Octobre 10-21, 2020 | |