Hypervelocity time-of-flight characterisation of a 14GS/s histogramming CMOS SPAD sensor

We present Time-of-Flight (TOF) distance, velocity and acceleration characterisation of a multi-event Time-to-Digital- Converter (TDC) optical sensor featuring a 32x32 Single Photon Avalanche Diode (SPAD) array, a 14 GS/s TDC and on-chip histogram generation. Events are continuously recorded on-chip in 264 70 ps-wide histogram bins. High TDC throughput enables the device to be operated in Doppler mode with pulse-trains moving at hypervelocity speeds relative to the operational sensor frequency. Electrical frequency-detuned signals of 50 kHz are resolved by the TDC module. Optical frequency-detuned signals of 1 kHz are resolved, corresponding to a TOF velocity resolution of 15.8 km/s. Linear, sine-wave, and chirp frequency modulation techniques are used to demonstrate these characteristics.