Ultra-high-performance digital-only analog-to-digital converters through time/frequency/phase domain optimization

Although today's electronic systems implement most of their functionality in the digital domain, several analog operations remain necessary, e.g. amplification, filtering and above all analog-todigital conversion. These analog circuits are preferably co-integrated with the digital circuits in today's nanometer CMOS technology. But this gives two important problems. First, the analog transistor performance (e.g. gain) is poor in such technologies. Secondly, the supply voltage has shrunk to 1 V or less, which dramatically limits the signal swing. As noise sources remain unchanged, and mismatches and interferences by nearby digital circuits are even increasing, the dynamic range is severely limited. This makes analog circuit design increasingly challenging. As a result, when moving to a more advanced CMOS technology, analog circuits do not become smaller in chip area, so not cheaper.

Therefore, the traditional way of building analog circuits needs to be rethought fundamentally towards a scalable, digital-only approach. Focus will be on the analog-to-digital converters. An important first step were the VCO-ADCs, but their performance is still limited today. The project's goal is to drastically boost the performance of digital-only solutions, both in bandwidth and in accuracy, by exploring innovative architectures. The basic idea is to use signal representations that can be represented by 2-level ("digital") waveforms and to optimally exploit the time/frequency/phase domain.