A 4-10 bit, 0.4-1V Power Supply, Power Scalable Asynchronous SAR-ADC in 40nm-CMOS withWide Supply Voltage Range SAR Controller

This paper presents a wide range in supply voltage, resolution, and sampling rate asynchronous successive approximation register (SAR) analog-to-digital converter (ADC). The proposed differential flipflop in SAR logic and high efficiency wide range delay element extend the flexibility of speed and resolution tradeoff. The ADC fabricated in 40 nm CMOS process covers 4-10 bit resolution and 0.4-1V power supply range. The ADC achieved 49.8 dB SNDR and the peak FoM of 3.4 fJ/conv. with 160 kS/sec at 0.4V single power supply voltage. At 10 bit mode and 1V operation, up to 10MS/s, the FoM is below 10 fJ/conv. while keeping ENOB of 8.7 bit.