Skiroc: A Front-end Chip to Read Out the Imaging Silicon-Tungsten Calorimeter for ILC

Integration and low-power consumption of the read-out ASIC for the International Linear Collider (ILC) 82-millionchannel W-Si calorimeter must reach an unprecedented level as it will be embedded inside the detector. Uniformity and dynamic range performance has to reach the accuracy to achieve calorimetric measurement. A first step towards this goal has been a 10,000-channel physics prototype of 18*18 cm which is currently in test beam in CERN. A new version of a full integrated read out chip (SKIROC) has been designed to equip the technologic prototype to be built for 2009. Based on the running physics prototype ASIC (FLC_PHY3), it embeds most of the required features expected for the final detector. The dynamic range has been improved from 500 to 2000 MIP. An auto-trigger capability has been added allowing built-in zero suppress. The number of channel has been doubled reaching 36 to fit smaller silicon pads and the lownoise charge preamplifier now accepts both AC and DC coupled detectors. After an exhaustive description, the measurement results of that new front-end chip will be presented. The results on the technological R&D concurrently conducted on the ultra-thin PCB hosting both the front-end electronic and the silicon detectors will also be described.