Dual mode stacked photomultipliers suitable for use in long range time of flight applications

摘要

A photomultiplier pixel cell includes a photon detector coupled to detect an incident photon. A quenching circuit is coupled to quench an avalanche current in the photon detector. An enable circuit is coupled to the photon detector to enable and disable the photon detector in response to an enable signal. A buffer circuit is coupled to the photon detector to generate a digital output signal having a pulse width interval in response to the avalanche current triggered in the photon detector. A first one of a plurality of inputs of a digital-to-analog converter is coupled to the buffer circuit to receive a digital output signal. The digital-to-analog converter is coupled to generate an analog output signal having a magnitude that is responsive to a total number of digital output signals received concurrently within the pulse width interval at each one of the plurality of inputs of the digital-to-analog converter.