A 40-nm CMOS Wide Input Range and Variable Gain Time-Difference Amplifier Based on Current Source Architecture.

A time-difference amplifier (TDA) with a wide timedifference input range and variable gain is presented in this paper. Its time amplification is performed using novel current source architecture, phase detection, and variable delay circuits. After time amplification, to avoid the current sources for charging and discharging capacitors simultaneously, a reset circuit is added. To widen the input time-difference range, an adjustable current source control is added. The proposed TDA is implemented using TSMC 40-nm CMOS process. The core area is 209.42 x84.775 mu m(2). Though our design is driven by a lower supply voltage, it has the widest time-difference input range and the largest FOM among all existing TDAs.