Digital domain accumulative cmos-tdi image sensor with low power consumption

A digital domain accumulative CMOS-TDI image sensor with low power consumption, comprising 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;
• K lines of pre-processing pixels are added into an n×m pixel array (n lines and m columns), the newly added k lines of pre-processing pixels are located to face a direction along which the original pixel array moves towards the object;
• the coarse quantification memory units, memory units for storage of n times of fine quantification results and the column parallel digital domain accumulator comprise a digital adder, a multiplexer, a memory array A, a memory array B, an one-way bus 1, a two-way bus 2, a two-way bus 3, a two-way bus 4 and an one-way bus 5;
• the memory array A functions to store fine quantification results therein, while the memory array B functions to store coarse quantification results therein;
• an output end of the SAR ADC is connected to an input end of the digital adder via the one-way bus 1;
• an output end of the digital adder and another input end of the digital adder are connected to the multiplexer through the two-way bus 2;
• a channel B of the multiplexer is connected with the memory array B through the two-way bus 3;
• a channel A of the multiplexer is connected with the memory array A through the two-way bus 4;
• and the memory array B is connected with a DAC of the SAR ADC via the one-way bus 5.