Amplifier read-out circuit with automatic adjustable gain

Abstract

The invention discloses an amplifier read-out circuit with an automatic adjustable gain. The amplifier read-out circuit comprises a capacitor feedback mutual conductance amplifier read-out circuit consisting of an integrating capacitor reset circuit and a gain adjusting integrating circuit; the integrating capacitor reset circuit consists of gating switches K4 and K5; the gain adjusting integration circuit consists of an operation amplifier OP1, integrating capacitors C1, C2 and C3 and gating switches K1, K2 and K3. The amplifier read-out circuit is characterized in that the read-out circuit is provided with a gain control circuit capable of automatically gating different capacitors; the gain control circuit automatically gates the different capacitors after comparing the integrating voltage of the integrating capacitor in the gain adjusting integrating circuit with the integrating voltage threshold value; and the gain control circuit consists of an operation amplifier OP2, a comparator, phase inverters I1, I2, I3 and I4 and triggers D1 and D2. Compared with the prior art, the amplifier read-out circuit disclosed by the invention can automatically amplify the gain of the weak signal of a photodetector, the sensitivity and signal-to-noise and the read-out of the large dynamic range can be increased, and the image quality can be ensured by adopting different methods to perform automatic settings as required.

Description

Technical field [0001] The invention relates to the technical field of circuit design, in particular to a gain automatic adjustable amplifier readout circuit. Background technique [0002] In many fields such as traffic management, security monitoring, industrial production, medical diagnosis, space observation, and military reconnaissance, the demand for solid-state image sensors is growing strongly. There are many indicators required for image sensors in practical applications. The most important ones are response spectrum, dynamic range, sensitivity, signal-to-noise ratio, resolution, etc. The type of detector determines the response spectrum, and the pixel size and spacing determine the resolution. Other indicators are largely determined by the readout circuit. The readout circuit (ROIC), as the signal conditioning and output part of the detector, plays a vital role in the performance of the detector assembly. The main function of the readout circuit in the photodetector is ...

AI Technical Summary

Problems solved by technology

The main disadvantage of this structure is that there will be errors in the experimental results of human observation, and it is difficult to ensure that the dynamic range of the readout is large and the sensitivity is high, resulting in inaccurate experimental results.

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