High-speed low-noise 8 channel BiCMOS preamplifier for silicon drift detector readout

We present the design and the experimental characterization of a novel 8 channel monolithic front-end preamplifier in 0.8 μm BiCMOS technology developed for the readout of high resolution silicon drift detectors having an integrated JFET source-follower stage. The preamplifier chip includes the low-noise current generator required to bias the on-detector JFET. The preamplifier tests showed fast rise-time constant (3 ns), linearity error better than 0.1% and crosstalk between channels less than 0.14% at 100 ns shaping time. The preamplifier has been successfully tested both at room temperature and at low temperature down to −40 °C. The Equivalent Noise Charge contribution of the preamplifier chip at 250 ns shaping time is 3.8 electrons rms at room temperature and 2.8 electrons rms at −40 °C.