Oxford University Thesis on Single-Slope ADCs

University of Oxford PhD thesis "Investigations of time-interpolated single-slope analog-to-digital converters for CMOS image sensors" by Deyan Levski explores time stretching and other concepts improving SS-ADC resolution and speed:

"The focus of the presented investigations here is to shed light on methods in Time-to-Digital Converter interpolation of single-slope ADCs. By using high-factor time-interpolation, the resolution of single-slope converters can be increased without sacrificing conversion time or power.

This work emphasizes on solutions for improvement of multiphase clock interpolation schemes, following an all-digital design paradigm. Presented is a digital calibration scheme which allows a complete elimination of analog clock generation blocks, such as PLL or DLL in Flash TDC-interpolated single-slope converters."