Time-to-Digital-Converter with small circuitry

A Time-to-Digital-Converter (TDC) is to measure the interval time between two signals, and its time resolution of several pico seconds is achieved when it is implemented with advanced CMOS process [1-5]. Its applications are gradually expanding such as a phase comparator of all-digital-PLL, a sensor interface circuit, modulation circuit and demodulation circuit as well as a TDC-based ADC. The TDC will play more important role in nano-CMOS era because it is well-matched to implement with fine digital CMOS process; it consists of mostly digital circuits, and as the switching speed increases, its performance is improved. This paper reports on a new TDC architecture with small circuitry (hence low power and low cost), fine time resolution and high linearity.