HARDROC2B: A Readout ASIC for INO-ICAL RPCs

The India-based neutrino observatory (INO) is an upcoming multi-purpose underground experiment in the Theni district of Tamil Nadu, with the main aim to determine the neutrino mass hierarchy. In order to satisfy the experimental requirements, the ICAL detector at INO will use 29000 Resistive Plate Chambers (RPCs) as the active detection element, which in turn requires millions of channels to be read out. In this paper, we report on the test results and integration of a new Front-end Application-Specific Integrated Circuit (ASIC), called HARDROC, with an RPC detector. The ASIC comprises 64 readout channels with a variable gain current preamplifiers followed by one slow and three fast shapers and a 10 bit-DACs in each channel. The present study includes the optimisation of various parameters such as preamplifier gain and DAC values for threshold settings. We will also present the important RPC performance results like hit registration efficiency and count rate variation with DAC values.