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

The ALICE1LHCB 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 tracking mode all the 50 mu m *425 mu m pixel cells in the 256*32 array are read out individually, whilst in particle identification mode they are combined in groups of 8 to form a 32*32 array of 300 mu m x 425 mu m cells. Radiation tolerance was enhanced through special circuit layout. Sensitivity to coupling of digital signals into the analog front end was minimized. System issues such as testability and uniformity further constrained the design. The circuit is currently being manufactured in a commercial 0.25 mu m CMOS technology. (28 refs).