Versatile multi-channel CMOS frontend with selectable full-scale dynamics from 100 MeV up to 2.2 GeV for the readout of detector's signals in nuclear physics experiments

We developed a versatile multichannel CMOS frontend with selectable full-scale energy range from 100 MeV up to 2.2 GeV for the readout of detector's signals in nuclear physics experiments. The core of the frontend electronics is a custom designed CMOS charge preamplifier able to guarantee an energy resolution of the order of 10 keV FWHM with a power budget of about 10 mW/channel (ASIC only). 16-channel charge preamplifiers are integrated in a single chip in ams 0.35 μm C35B4C3 technology together with the CsI(Tl) frontend and few additional slow control services. A dedicated 8 layer frontend motherboard houses 2 ASICs and the line-drivers needed to provide a differential output and to drive the several-meter long connections. High-density right-angle open-pin-field connectors interconnect the motherboards and a patch-panel responsible of the slow-control and the interconnections to the meters-long cables. The designed frontend is extremely versatile, being suitable to be coupled to different detector topologies and signal polarities with capacitances ranging from about 10 pF up to about 200 pF. The first application of the developed frontend is to instrument the FARCOS (Fem-toscope ARray for Correlation and Spectroscopy) detection system, a novel detector featuring high angular and energy resolution able to reconstruct the particle's momentum at high precision and capable of performing correlation measurements of LCPs and of LCPs and IMFs. A thorough experimental qualification allowed verifying the frontend performance. The measured energy resolution with the frontend coupled with a 300 μm thick Double Sided Silicon Strip Detector (DSSSD) of the FARCOS telescope illuminated with a mixed-nuclei α source shows a resolution below 10 keV FWHM. The paper focuses on the designed frontend system and on the results of its qualification.