چكيده به لاتين
Abstract
In this project, in addition to full review on the light-sensitive areas in 90nm CMOS technology, design and simulation of three image sensor enhanced by energy harvesting from ambient light is completely done.
Efforts have been made in the trends of keeping the sensor power consumption to be low, while imaging characteristics and energy harvesting rates become maximum. For this purpose, the main idea of the four-transistor pixels is used in the energy harvesting and imaging sensors.
In this project a nanometer CMOS technology has been used to design energy harvesting and imaging sensors that up to this time has not been reported in any article.
The project's main sensor is a pixel structure with 17µm pixel pitch that designed in 90nm CMOS technology and use from p+/n-well/p-sub double junction in its photosensitive area and floating diffusion.
In this structure with using dual exposure time method in a particular structure, dynamic range of 68.96 dB is achieved which is the highest dynamic range reported for a linear energy harvesting and imaging sensor.
This sensor has the power consumption of 61.43 pW per pixel at 25 fps frame rate and power generation of 1.67 nW per pixel at light intensity of 60 klx.
The suggested pixel has been provides the conversion gain of 1.69 μV⁄e^- . Achieving to the desired dynamic range and conversion gain at the same time is the result of using main idea of four-transistor structures. Also achieving high dynamic range with relatively low power consumption, is caused by the use of some low power methods such as p-type reset transistor and dual exposure time, and also some low power considerations which used in the design of them to reduce power consumption.
Keywords: CMOS image sensor, energy harvesting, low power sensors, high dynamic range.
