Ramp generator for read-out circuit of infrared focal plane array detector

Abstract

The embodiment of the invention discloses a ramp generator for a read-out circuit of an infrared focal plane array detector. The ramp generator comprises a switch control module, a ramp generation circuit and a voltage rise circuit, wherein the switch control module comprises a data input end and n output control ends; the ramp generation circuit comprises n control ends and a data output end; the n control ends are connected with the n output control ends of the switch control module in a one-to-one correspondence mode; the voltage rise circuit comprises a rise input end and a rise output end; the data output end of the ramp generation circuit is connected to the rise input end; and n is a natural number which is more than or equal to 2. According to the embodiment of the invention, slope can be sectionally adjusted, the output current of the ramp generator approximates a fitting curve, and the phenomena that the utilization rate of digital codes is reduced, and nonlinearity is caused because low-temperature simulation response is low are avoided.

Description

technical field [0001] The invention relates to a readout circuit of an infrared focal plane array detector, in particular to a ramp wave generator for the readout circuit of an infrared focal plane array detector. Background technique [0002] According to Planck's radiation theorem, any object with a temperature higher than absolute zero will have molecular thermal motion inside it, thereby producing infrared radiation with different wavelengths. Infrared radiation has an important feature that its intensity and wavelength are directly related to the surface temperature of the object, providing rich information about the object. However, infrared radiation is an invisible electromagnetic wave. When using infrared radiation to obtain information about objects, it is necessary to convert this infrared radiation into a measurable signal. [0003] An infrared focal plane array detector is a device that converts infrared radiation into a measurable signal. The infrared focal ...

AI Technical Summary

Problems solved by technology

However, the radiance does not increase linearly with temperature

[0005] When the infrared focal plane array detector is working, due to the nonlinearity of infrared radiation, the influence of the target temperature change on the temperature of the sensitive unit is nonlinear. After conversion by the linear Single-Slope ADC, the digital output and the detected target temperature are nonlinear, and The change is slow at low temperature and rapid at high temperature, so the detection details of low-temperature objects are not clear, and high-temperature objects may over-response

In addition, due to the low response at low temperature, the lower analog voltage is almost impossible to appear in practice, so the lower digital code becomes a "dead code", resulting in a lower effective utilization of the digital code

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