Operation of p-n Junction Photodetectors in a Photon Flux Integrating Mode

CMOS Photodetectors

“…As discussed in [42], this voltage drop is usually linear for a wide range of values below V DD . Therefore, the voltage readout at the end of the integration period can be used as a measurement of the amount of light that has fallen on the pixel during the integration phase.…”

A Digital Pixel Sensor Array With Programmable Dynamic Range

“…The photodetector operates in photon flux integration mode, where the photocurrent is integrated over time in order to produce a large change in the stored charge, and consequently, the signal voltage. This mode of operation is commonly used by most CMOS voltage mode photodetectors, and results in the junction voltage decaying at a virtually constant rate, despite the junction capacitance being voltage dependent [14]. The photodiode sensor is reverse-biased by a fixed voltage source , which fully charges the photodiode junction capacitance .…”

A VLSI sorting image sensor: global massively parallel intensity-to-time processing for low-latency adaptive vision

“…3 shows the simulation of the circuit operation for the sorting sensor with four cells. A photodiode operating in the photon flux integrating mode [21] detects the light. In this mode of operation the capacitance of the diode is charged to a high potential and left to float.…”