DocumentCode :
86973
Title :
Design of a Multichannel Low-Noise Front-End Readout ASIC Dedicated to CZT Detectors for PET Imaging
Author :
Gao, Wenzhong ; Liu, Hongying ; Gan, B. ; Wei, Ta-Chin ; Gao, Dayong ; Hu, Ya
Author_Institution :
Sch. of Comput. Sci. & Technol., Northwestern Polytech. Univ., Xian, China
Volume :
61
Issue :
5
fYear :
2014
fDate :
Oct. 2014
Firstpage :
2532
Lastpage :
2539
Abstract :
In this paper, we present the design and preliminary results of a novel low-noise front-end readout application-specific integrated circuit (ASIC) for a PET imaging system whose objective is to achieve the following performances: the spatial resolution of 1 mm3, the detection efficiency of 15% and the time resolution of 1 ns. A cascode amplifier based on the PMOS input transistor is selected to realize the charge-sensitive amplifier (CSA) for the sake of good noise performances. The output of the CSA is split into two branches. One is connected to a slow shaper for energy measurements. The other is connected to a fast shaper for time acquisition. A novel monostable circuits is designed to adjust the time delay of the trigger signals so that the peak value of the shaped voltages can be sampled and stored. An eight-channel front-end readout prototype chip is designed and implemented in 0.35 μm CMOS process. The die size is 2.286 mm ×2.282 mm. The input range of the ASIC is from 2000 e- to 180000 e-, reflecting to the energy level of the gamma ray from 11.2 keV to 1 MeV. The gain of the readout channel is 65 mV/fC. The tested result of ENC is 86.5 e- at zero farad plus 9.3 e- per picofarad. The nonlinearity is less than 3%. The crosstalk is less than 2%. The power dissipation is about 3 mW/channel.
Keywords :
CMOS integrated circuits; application specific integrated circuits; crosstalk; gamma-ray detection; positron emission tomography; readout electronics; semiconductor counters; trigger circuits; CMOS process; CZT detectors; PET imaging system; PMOS input transistor; cascode amplifier; charge-sensitive amplifier; crosstalk; detection efficiency; electron volt energy 11.2 keV to 1 MeV; energy measurements; front-end readout prototype chip; gamma ray energy level; low-noise front-end readout application-specific integrated circuit; monostable circuits; multichannel low-noise front-end readout ASIC; noise performances; peak value trigger signals; power dissipation; readout channel gain; shaped voltages; spatial resolution; time acquisition; time resolution; trigger signals; Application specific integrated circuits; Detectors; Energy resolution; Noise; Positron emission tomography; Resistors; ASIC; PET imaging; front-end electronics; low noise; readout circuits;
fLanguage :
English
Journal_Title :
Nuclear Science, IEEE Transactions on
Publisher :
ieee
ISSN :
0018-9499
Type :
jour
DOI :
10.1109/TNS.2014.2356465
Filename :
6910333
Link To Document :
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