A 52 PS Resolution ILO-Based Time-To-Digital Converter Array for LIDAR Sensors
Additional Document Info
2016 IEEE. Light detection and ranging (LIDAR) systems offer fast detection and high spatial resolution for imaging and mapping in a host of applications, such as robotics, automotive, agriculture, military, and spaceflight. This paper presents a high-resolution LIDAR sensor system-on-a-chip (SoC) prototype containing a 312 pixel channel array with the input time-of-flight (ToF) resolved by a 321 time-to-digital converter (TDC) array. A novel TDC design employs injection-locked oscillators (ILOs) to both minimize TDC clock distribution power and improve time accuracy. Global PVT variations among the ILOs is calibrated by an on-chip phase-looked loop (PLL) that ensures good circuit reliability over a wide operating range. Fabricated in GP 65 nm CMOS, the 14-bit TDC consumes 788 W/channel and achieves 52 ps resolution over an 830 ns full-scale range, 37.2 psrms single-shot precision, 11 psrms channel uniformity, and DNL/INL of 0.56/1.56 LSB, respectively. This electrical characterization projects that with future integration with stacked-die avalanche photodiodes (APDs) the SoC has the potential for 0.78 cm ranging precision over a 124 meter maximum ranging distance.
name of conference
2016 IEEE Dallas Circuits and Systems Conference (DCAS)