The Design Of Peak-detector ASIC

With the development of technology and the living standards of people constantly improving, people are increasingly concerned about their own environment. But radioactive contamination with the characteristics of colorless and odorless is a more serious environmental contamination, and has become one of the most serious social problems because it is deadly up to a certain dose. To understand promptly the pollution situation which the radionuclide decay causes, needs to use the special instrument to carry on the survey.The primary function of nuclear radiation detectors is to make change of the signal enter the sensitive area of nuclear radiation detector into processing signals which device can detect. The signal sent out by nuclear radiation detectors needs signal processing, peak detection, A/D conversion to get the digital signals which can identify by the Back-end PC. The peak detection circuit (PKD) is an important circuit unit between the pre-amplifier and A/D converter, which the degree of development greatly limits the improvement of overall system performance. Thus, with the maturation and development of the domestic semiconductor process and IC design technology, the peak detection application specific integrated circuit (peak detector ASIC)has been used as a separate design module to study in nuclear radiation detectors front-end read-out chip, as a hot topic in related fields of the domestic and foreign.In this paper, the overall design and simulation of the peak detection circuit is based on the csmc0.5 process, and the peak-discriminator improved by using the differential zero-crossing comparator circuit achieves the peak-time discrimination to trigger the ADC to transform the peak-voltage into digital and trigger the circuit to reset PKD after ADC conversion. This peak detection circuit is mainly designed to achieve the shielding of noise and other weak signal, the peak holding and the peak-time discrimination.