A 13.73 ns Input Time Range TDA Design Based on Adjustable Current Sources Using 40-nm CMOS Process

This study presents a time-difference amplifier (TDA) based on adjustable current sources. The proposed amplifier uses a phase detection circuit, delay element, and current source architecture for time-difference (i.e., delay) amplification. It includes a reset circuit that prevents the capacitors in the current sources from charging and discharging simultaneously. In addition, an adjustable current source control increases the range of input time difference. The TDA design is implemented in TSMC 40-nm technology with \(964.24 \times 961.81\) $964.24\times 961.81$  µm \(^2\) ${}^2$ overall chip area and \(209.42 \times 84.76\) $209.42\times 84.76$  µm \(^2\) ${}^2$ core area. The TDA achieves the widest time-difference input range of ± 13,730 ps, less than 4% gain error, the lowest supply voltage, and the highest FOM compared to prior TDAs.