CMOS focal plane readout circuit and signal readout control method

Abstract

A CMOS focal plane readout circuit, the innovation of which is: the position of a certain pixel in the two-dimensional focal plane array is expressed by the mark Celln,m, where n represents the position of the pixel in the two-dimensional focal plane array The number of rows, m represents the column number of the pixel in the two-dimensional focal plane array; then the output terminal of the pixel marked as Celln,m is respectively connected with the cell marked as Celln‑1, m, Celln+1 through four connecting wires ,m, Celln,m‑1 and Celln,m+1 are electrically connected to the output ends of the four picture elements; the connecting wire is provided with a connection switch. The beneficial technical effects of the present invention are: the selective inflow of photo-generated current output by the pixel to the sampling unit can be realized through the switch, the sensitivity of the focal plane imaging system can be improved, and the dynamic range can be expanded.

Description

technical field [0001] The invention relates to a CMOS focal plane readout technology, in particular to a CMOS focal plane readout circuit and a signal readout control method. Background technique [0002] The focal plane imaging system includes a focal plane imaging device (ie, a focal plane array) and a focal plane readout circuit. The basic principle is: the photo-generated current generated by the pixel on the focal plane array is conducted to the sampling unit of the readout circuit through the indium column, and the photo-generated current signal is sampled and integrated by the sampling unit, and then converted into a corresponding voltage signal, and then passed through the sampling unit. The subsequent column-level processing circuit buffers the readout and finally image; common sampling units in the prior art such as capacitive feedback transimpedance amplifier (CTIA) sampling unit, direct injection type (DI) sampling unit, source follower type (SFD) Sampling unit...

AI Technical Summary

Problems solved by technology

[0003] The problem existing in the prior art is: in the existing focal plane imaging system, multiple pixels in the focal plane array and the sampling unit adopt a one-to-one correspondence connection mode, that is, the output signal of one pixel is processed by one sampling unit; In some occasions, it may appear that the photo-generated signal output by the pixel is relatively weak. At this time, the weak photo-generated signal may be submerged in the noise of the device, making it difficult for the sampling unit to sample and output it.

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