A four-channel bipolar monolithic preamplifier for RHIC dimuon pad readout

The authors present a four-channel, low-power-consumption bipolar monolithic preamplifier designed to amplify signals from pads with detector capacitance values from 20 pF to 50 pF used in an RHIC (Relativistic Heavy Ion Collider) dimuon experiment. The circuit utilizes a folded-cascode topology with a novel feedforward compensation that improves the low-capacitance transient response and provides self-biasing without resorting to bandgap or current references. The circuit was fabricated in the VHF dielectrically isolated complementary bipolar process. Data for gamma pre- and post-irradiation to 1.25 Mrad indicated that the dynamic characteristics of the circuit were unchanged and that the biasing and noise showed only a few percent change after exposure to radiation.<>