The images sensor includes a readout circuit capacitatively coupled to a memory circuit. The readout circuit includes: (i) a photon detector to receive a plurality of photons and to provide a charge signal corresponding to the received photons, (ii) a resettable integrator that is reset multiple times over a single exposure time and provides an analog representation of the incident photons during the last integration cycle, and (iii) a comparator that monitors the integrator output and generates a reset pulse when the integrator reaches a built-in threshold value. The memory circuit includes: (i) a receiver circuit that detects the output of the digital driver in the front-end readout circuit via capacitive coupling and generates a digital voltage pulse for each received signal, and (ii) a digital counting memory to count the received pulses to provide a coarse digital representation of how many times the integrator is reset.