Infrared array focal plane read-out circuit

Abstract

The invention discloses an infrared array focal plane read-out circuit which comprises a load resistor shunt circuit, a load switch control circuit, a capacitor transconductance feedback and amplifier circuit, an integral / resetting control unit circuit, a storage unit circuit, a correlated double-sampling circuit, an integral gating control circuit and a CDS (correlated double sampling) gating control circuit. The load switch control circuit is controlled by a DA (digital to analog) convertor, so that the problems that integral current is overheavy due to ununiformity of pixels and reference pixels and high resistance difference between the pixels and the reference pixels when a TEC (temperature controller) module is adopted. Complementary switches are used for weakening the charge injection effect. The level can be read out by a two-stage streamline scheme, wherein an integral control unit adopts a multi-way gating parallel integration storage manner, the CDS circuit adopts a one-way output manner, different pixel signals are sequentially output by controlling gating signals, integration and signal read-out can be carried out simultaneously by the two-stage streamline scheme, so that time utilization rate is increased, chip complexity is reduced and power consumption of chips is lowered.

Description

technical field [0001] The invention relates to a circuit. Specifically, it is an infrared column focal plane readout circuit in an infrared imaging system. Background technique [0002] With the development of science and technology, infrared imaging technology is becoming more and more mature, and it has been widely used in military, space technology, civilian and other aspects. The infrared focal plane array component is the core component of the infrared imager. The component is composed of an infrared detector array and a readout circuit (ROIC: Read-Out Integrated Circuits). The ROIC circuit is an important factor affecting the performance of the component. The design of the ROIC circuit has always been Towards low cost, low power consumption, high speed and high performance. [0003] Common ROIC circuits are composed of unit circuits, row and column gating circuits, logic sequence control circuits, and output buffer circuits. The basic functions realized by the un...

AI Technical Summary

Problems solved by technology

Among them, the CTIA-type readout structure has the advantages of good linearity, good uniformity, and large dynamic range, which are difficult to have in other structures, except that the circuit structure is relatively complicated and the power consumption is large, and it can also be connected with the correlated double sampling (CDS) circuit structure. , to eliminate the influence of reset noise and KTC noise, in addition, due to the non-uniformity of pixels and reference pixels, it also affects the response rate of CTIA-type readout circuits

[0005] The current readout method of the infrared focal plane mainly includes converting the detector signal first and then outputting the signal, or adopting a pipeline method, the detector signal conversion and signal output are carried out at the same time, the latter can make full use of time and have high efficiency, but the readout The circuit is often designed more complicated, resulting in a large readout circuit, large power consumption, and high cost

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