Preamplifier with wide dynamic reading range at front end of radiation detector

Abstract

The invention discloses a preamplifier with a wide dynamic reading range at the front end of a radiation detector, which is characterized in that the preamplifier can automatically adjust the size ofa feedback capacitor according to the size of an input signal so as to realize automatic adjustment of conversion gain. The preamplifier is composed of a single-ended charge sensitive amplifier CSA, avoltage comparator VCM, a first D trigger D1 and a second D trigger D2. Compared with an existing radiation detector front-end read-out amplifier, the preamplifier has an automatic gain adjustment function, the gain is adjusted to be high when the charge quantity is low, the gain is automatically switched to be low when the charge quantity is high, both the first D trigger D1 and the second D trigger D2 adopt D triggers with asynchronous reset, and a first switch SW1, a second switch SW2 and a reset switch SWR adopt improved transmission gate circuits, so that the influence of a charge injection effect on the circuit is effectively reduced, and the input dynamic range of the front-end read amplifier is expanded.

Description

technical field [0001] The invention belongs to the field of reading out the front end of a radiation detector, in particular to a preamplifier for reading out a wide dynamic range at the front end of a radiation detector. Background technique [0002] In recent years, due to the gradual expansion of the energy range of particles measured by semiconductor radiation detectors, the dynamic range of the charge signal output from the detector to the front-end readout circuit has become larger and larger, which can range from several fC to pC levels. The weak charge signal output by the device is integrated and amplified, and the charge signal is converted into a voltage signal, and then filtered and noise-reduced. When the signal range input to the front-end readout circuit is too large, the conversion gain of the preamplifier originally fixed and the high conversion gain front-end amplifier circuit will be saturated with the increase of the input signal, which cannot meet the d...

AI Technical Summary

Problems solved by technology

When the signal range input to the front-end readout circuit is too large, the conversion gain of the preamplifier originally fixed and the high conversion gain front-end amplifier circuit will be saturated with the increase of the input signal, which cannot meet the design requirements of semiconductor radiation detectors.

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