In-pixel time-to-digital converter for 3D TOF cameras with time amplifier

Abstract

In this paper, a novel in-pixel time-to-digital converter (TDC) for 3D time-of-flight cameras is presented. Coarse---fine architecture has been used to guarantee both wide dynamic range and high time resolution. The proposed TDC exploits pulse-train time amplifier (TA) to further improve the time resolution and optimize time error performance. The 11-bit TDC provides 62.5 ps resolution and 126 ns full-scale range. Simulation results indicate the TDC achieves a DNL of under 0.52 LSB and INL less than 0.8 LSB. Both the TA and TDC are designed in GSMC CIS 0.18 μm 1P6M technology.