We present a successive approximation register analog-to-digital converter (ADC) that employs a comparator with time-varying noise performance, realized by changing the integration time of a Gm-C preamplifier. This approach allows us to relax precision and enhance speed during noncritical decisions, leading to an aggregate speed-up of 22% compared to a conventional design. The ADC operates at 30 MS/s, achieves a peak signal-to-noise and distortion ratio of 77.2 dB, and consumes 38 mW from 1.2 V/2.5 V supplies, corresponding to a Schreier FOM of 163.1 dB (161.6 dB at Nyquist). The proof-of-concept converter is implemented in a 40-nm LP complementary metal-oxide semiconductor process and occupies 0.24 mm2.
|Number of pages||5|
|Journal||IEEE Transactions on Circuits and Systems II: Express Briefs|
|Publication status||Published - 1 Feb 2017|
- Analog-to-digital converter (ADC)
- complementary metal-oxide semiconductor (CMOS)
- successive approximation register (SAR)