Bohner “A Charge-Sensitive Amplifier Associated with APD or PMT for Positron Emission Tomography Scanners” MIPRO 2009

Abstract- We present a Charge-Sensitive Amplifier (CSA) to be coupled with a 511-KeV 2-photon detector for positron emission tomography scanners. The circuit has been designed to be associated with an Avalanche Photodiode (APD) or Photo-Multiplier Tube (PMT) with large capacitance. It is a two-stage structure. The input stage consists of a folded-cascode fully-differential part and a common-mode feedback (CMFB) circuit. The output stage employs complementary source followers. The amplifier has been designed in a 0.35µm BiCMOS process with optimization of noise and speed performances to meet specific constraints. Its main characteristics evaluated by post-layout simulations are: 70-dB DC gain, 4.6-GHz GBW, 20-ns peaking time for pulsed stimulus, 3900-electron equivalent input noise charge (ENC), 135-mW power consumption at 3.5 V supply