Focal plane readout circuit with multiple working modes and its control method

Abstract

The invention discloses a focal plane readout circuit with multiple working modes. The focal plane readout circuit is composed of a plurality of CTIA sampling units, and the plurality of CTIA sampling units are distributed in the form of an array. In the array, the A plurality of CTIA sampling units on the network is recorded as a sampling column, and the structure of each sampling column is the same; a single sampling column is composed of multiple amplifiers, multiple integrating capacitors and multiple reset switches; if the number of amplifiers in a single sampling column is recorded as n, the integral capacitance quantity in the single sampling row is recorded as N, then N=n+1; The quantity of reset switch is identical with the quantity of integral capacitance; Beneficial technical effect of the present invention is: provide a kind of focus of multiple working modes The planar readout circuit and its control method, the focal plane readout circuit can greatly reduce the required integral capacitor quantity under the condition of the same number of sampling units.

Description

technical field [0001] The invention relates to a focal plane readout circuit, in particular to a focal plane readout circuit with multiple working modes and a control method thereof. Background technique [0002] The focal plane imaging system usually includes two parts, the focal plane detector and the focal plane readout circuit. After the output signal of the readout circuit is processed by the post-stage circuit, a complete image can be obtained. [0003] In the prior art, the CTIA sampling unit is widely used in the focal plane readout circuit due to its advantages of low noise and high linearity. The existing CTIA sampling unit is generally equipped with two integrating capacitors, one large and one small. The small integrating capacitor is used to convert weak light into a voltage signal under high background conditions, and the large integrating capacitor is used to convert strong light into a voltage signal under low background conditions. Voltage signals, the tw...

AI Technical Summary

Problems solved by technology

[0004] Under the existing technical conditions, the integral capacitor usually adopts MOS capacitor, PIP capacitor or MIM capacitor, and the integral capacitor will occupy a large space on the area of ​​the sampling unit. For example, the small integral capacitor is 5fF, and the large integral capacitor is 120fF. µm 2 PIP capacitor, the small integral capacitor needs 2.5µm 2 area, a large integral capacitor requires 60µm 2 For a sampling unit size of 15µm×15µm, two integrating capacitors will occupy 27.8% of the area, and if the necessary isolation between capacitors is taken into account, about 30% of the area will be required, resulting in a large sampling unit area, which is not conducive to Device miniaturization

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