Applications for Time-to-Digital Converters

Abstract

Amongst other things, time-to-digital converters are used in high energy and particle physics, for measurement and instrumentation applications, for time of flight measurement, digital PLLs, and data converters. This chapter focuses on emerging applications in main stream micro-electronics. In the first part time-to-digital converters are discussed in the context of digital phase-locked loops. Both the classical PLL architecture based on a feedback divider as well as the recently proposed all-digital PLL architecture are discussed. The second part addresses time-to-digital converter based analog-to-digital converters.¹ The classical dual slope converter is revisited for motivation purposes. Next an ADC based on pulse position modulation is discussed. Finally, sigma delta modulator based ADCs are investigated. A continuous time sigma delta modulator with time domain quantizer is presented as a classic approach and an ADC based on an asynchronous sigma delta modulator with feed-forward TDC as quantizer is presented as promising new architecture for ultimately scaled CMOS. It is the intention of this chapter to provide an overview on concepts and architectures, not to focus on implementation details.