Smart-pixel array for imaging sensors

Abstract

This paper describes a CMOS smart-pixel array for applications in microchip size imaging sensor with pixel-level analog to digital conversion. This on-chip conversion is performed using a one-bit first-order sigma-delta converter for each pixel. The sensor outputs digital data in the form of bit streams containing information about the intensity of the incident light. The electronics circuits have been designed for occupying a very small chip area. Each pixel block consists of a photodiode and 19 mosfets. The sensor, the readout circuits and the digital interface are integrated on a single CMOS chip.