A high precision time-difference amplifier based on tri-state inverter

The traditional three-state inverter based time-difference amplifier (TDA) has the characteristics of low circuit complexity, insensitivity to voltage margin and temperature, but the structure has low time resolution, large gain error and relatively narrow application range. An improved TDA structure that achieves high-precision gain by redesigning the delay chain control signal generation circuit is presented in this paper.Measurement results of Spectre based on 40 nm CMOS process show that the proposed TDA not only has stable and controllable gain (gain error is less than ±4%) and high time resolution (up to 380 fs), but the input range is further improved.