All-Digital CMOS Pulse-Shrinking Time-to-Digital Converter With Built-in Offset-Error Cancellation and Smart Temperature Sensor

This brief presents an all-digital CMOS time-to-digital converter (TDC) with an integrated smart temperature sensor (STS), effectively reducing circuit complexity and cost. Unlike previous designs employing a single coupling unit, the proposed TDC adopts a two-coupling-unit structure, simplifying the overall architecture while enabling pulse-shrinking time measurement and offset-error cancellation within a single cyclic delay line. The built-in cancellation enhances linearity while minimizing overhead. Notably, the integrated STS requires only one additional coupling unit, ensuring a negligible impact on circuit complexity and cost. Fabricated using the TSMC 0.35- $\mu $ m CMOS process, the proposed design demonstrates improved cost efficiency compared to prior works. Experimental results validate the successful measurement of time and temperature, highlighting the advantages of reduced complexity and cost savings.