Tianjin University

Suying Yao

Zaifeng Shi

Jing Gao

Jiangtao Xu

Kaiming Nie

Zhiyuan Gao

Cen Gao

The present invention relates to technical field of analog integrated circuit design. TDI function is better realized by CMOS image sensor and it improves scanning frequency of the CMOS-TDI image sensor and extends application range of TDI technique. To this end, the present invention proposes a technical solution of high scanning frequency CMOS-TDI image sensor. The pixels include a photodiode, an operational amplifier, integration capacitors Cand Cof the same capacitance, an offset voltage removing capacitor C, and plural switches S-S. The anode of the photodiode is connected to a zero voltage ground wire, while the cathode thereof is connected to one end of the switch S. The other end of the switch Sis connected to a reference voltage V. The above pixels are cascaded and an output end of the last pixel is connected to a column-parallel ADC through a readout switch Read. The invention mainly applies to analog integration circuit design.

High scanning frequency CMOS-TDI image sensor

The present invention relates to a CMOS image sensor. The present invention provides a digital pixel sensor capable of maintaining consistency between two reference voltage changing rates. To this end, the invention proposes a technical solution in which a digital pixel exposure method by using multiple ramp voltage as reference voltage is provided. Said method includes the following steps: by means of PWM pixel array, a PWM pixel is composed of a photodiode PD, a reset transistor MRST, a pixel or column level comparator, and a pixel or column or array level memory; the two input ends of the pixel level comparator are connected with PD node voltage and a predefined reference voltage V; after being reset, the PWM type digital pixel undergoes an exposure period; the exposure time includes a reset sampling period Tand an integration sampling period T; in resetting sampling period, reference voltage Vlinearly rises from Vto V; The integration sampling period is divided into several sub periods. The present invention mainly applies to design and manufacture of CMOS image sensors.

Digital pixel exposure method by using multiple ramp voltage as reference voltage

The present invention relates to technical field of analog integrated circuit design. TDI function is better realized by CMOS image sensor and it improves scanning frequency of the CMOS-TDI image sensor and extends application range of TDI technique. To this end, the present invention proposes a technical solution of a current accumulative pixel structure for CMOS-TDI image sensor which comprises a photodiode, four MOS transistors M, M, M, M, four switches S, S, S, S, and two capacitors C, C; the connection relationship thereof is denoted below: the anode of the photodiode Dis connected to a ground wire, while the cathode thereof is connected to an input end; the drain and gate of the transistor Mare both connected with the input end, while the source thereof is connected with a power source VDD. The current invention mainly finds its application in analog integration circuit design.

Current accumulative pixel structure for CMOS-TDI image sensor

The present invention relates to the field of design of analog digital hybrid integrated circuit. The object of the invention is to reduce ADC conversion rate thus further reducing power consumption of the sensor while not reducing line frequency of the CMOS-TDI. To this end, a digital domain accumulative CMOS-TDI image sensor with low power consumption is provided. It includes a pixel array of n+k lines multiplied m columns, a column parallel signal pre-processing circuit, a column parallel successive approximation (SAR) ADC, a column parallel digital domain accumulator, a column parallel divider, a timing control circuit and an output shift register, wherein n+k+1 coarse quantification memory units are provided to the column parallel digital domain accumulator for storage of coarse quantification results; and memory units for storage of n times of fine quantification results are also provided, thus realizing n stages of TDI signal accumulation after accumulation of n times of fine quantification results. The invention is generally used in hybrid integrated circuit design.

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Tianjin, China

Suying Yao