A low-noise, wide-band CMOS charge-sensitive preamplifier for use with APD/LSO PET detectors
- CTI, Inc., Knoxville, TN (United States)
- Univ. of Tennessee, Knoxville, TN (United States). Electrical and Computing Engineering Dept.
The recent emergence of LSO as a potential scintillator for positron emission tomography (PET) and recent improvements in avalanche photodiode (APD) technology offer encouragement that an APD/LSO based PET detector may be commercially viable in the near future. An important component of any APD/LSO based PET detector will be the preamplifier used to read out the low-level detector signals. Due to the large number of detectors (>18,000) in a high-resolution PET scanner, the preamplifier must be implemented as a monolithic integrated circuit. Additionally, in order to achieve the timing resolution required for high resolution PET, the preamplifier must have a large band-width and a low equivalent input noise voltage. This paper presents a CMOS charge-sensitive preamplifier design which uses local feedback to improve the performance of the common gate transistor. The modified cascode circuit is analyzed and compared with a previously reported simple folded cascode circuit. A prototype circuit was fabricated in a 2 {micro}m NWELL CMOS process. The prototype amplifier has a measured 10--90% rise-time of 7 ns with an external input capacitance of {approximately}6 pF and has an equivalent input noise voltage of {approximately}1.1 nV/rt-Hz above the flicker noise corner. A pulse height resolution of 14.3% FWHM and a timing resolution of 1.57 ns FWHM (vs. plastic) were obtained with the preamplifier, an Advanced Photonix 5 mm diameter beveled-edge APD and a 3.5 x 3.5 x 22 mm{sup 3} Teflon wrapped LSO crystal.
- OSTI ID:
- 276477
- Report Number(s):
- CONF-951073--
- Journal Information:
- IEEE Transactions on Nuclear Science, Journal Name: IEEE Transactions on Nuclear Science Journal Issue: 3Pt2 Vol. 43; ISSN IETNAE; ISSN 0018-9499
- Country of Publication:
- United States
- Language:
- English
Similar Records
A low-noise, wideband, integrated CMOS transimpedance preamplifier for photodiode applications
X-ray and gamma ray detector readout system