Pixel readout chips in deep submicron CMOS for ALICE and LHCb tolerant to 10 Mrad and beyond

The ALICEILHCB chip is a mixed-mode integrated circuit designed to read out silicon pixel detectors for two different applications: particle tracking in the ALICE Silicon Pixel Detector and particle identification in the LHCb Ring Imaging Cherenkov detector. To satisfy the different needs for these two experiments, the chip can be operated in two different modes. In tracki ng mode all the 50 mum x 425 mum pixel cells in the 256 x 32 array are read out individually, whilst in particle identification mode they are combined in groups of 8 to form a 32 x 32 array of 400 mum x 425 mum cells. Radiati on tolerance was enhanced through special circuit layout. Sensitivity to co upling of digital signals into the analog front end was minimized. System i ssues such as testability and uniformity further constrained the design. Th e circuit is currently being manufactured in a commercial 0.25 mum CMOS tec hnology. (C) 2001 Elsevier Science B.V. All rights reserved.