CMOS image sensor, and pixel circuit and driving method thereof

Abstract

The embodiment of the invention provides a CMOS image sensor, and a pixel circuit and a driving method thereof, and relates to the technical field of image collection. Additional interface circuits in an IC can be avoided. A pixel circuit collection module of the CMOS image sensor is used for collecting incident light, converting the collected light signal into an electric signal and outputting the electric signal to a source following module; the source following module is used for amplifying and buffering the received electric signal under the control of a scanning line and outputting the electric signal to a collection signal output end; a voltage conversion module comprises a current mirror and a boost sub-module, the current mirror is used for providing offset current to the boost sub-module and the source following module through a reading signal line under the action of a current source and a first voltage end; and the boost sub-module is used for converting the voltage of the collection signal output end into an output voltage under the action of the offset current provided by the current mirror and a second voltage end, and the output voltage is located within the working voltage range of an image processor.

Description

technical field [0001] The invention relates to the technical field of image acquisition, in particular to a CMOS image sensor, a pixel circuit and a driving method thereof. Background technique [0002] Image sensors are classified into complementary metal oxide (Complementary Metal Oxide Semiconductor, CMOS) image sensors and charge coupled device (Charge Coupled Device, CCD) image sensors, which are usually used to convert optical signals into corresponding electrical signals. In contrast, CMOS image sensors are widely used in digital cameras, mobile phones, medical equipment, automobiles, etc. because of their simple process, easy integration with other devices, small size, light weight, low power consumption, and low cost. occasion. [0003] The pixel unit (Pixel) of the above-mentioned CMOS image sensor is provided with a pixel circuit composed of a plurality of transistors and a photodiode (Photo Diode, PD). The above multiple transistors may be CMOS transistors or ...

AI Technical Summary

Problems solved by technology

In this case, since the working voltage of the integrated circuit (Integrated Circuit, IC) receiving the output signal of the pixel circuit is a positive voltage, in order to match the output voltage of the pixel circuit with the IC, an additional interface circuit needs to be added to the IC , which will lead to an increase in the production cost of the IC

Images