The ATLAS calorimeter calibration board - Tests of a first set of boards - New developments

The ATLAS Liquid Argon electromagnetic calorimeter needs a very accurate calibration system in order to fulfill its physics requirements. A set of 10 calibration boards has now been produced to test the calorimeter modules in electron beam. These boards contain a programmable sequencer which allows the loading and execution of a complete calibration run (various DAC values, delays and patterns) and provide 128 signals which are injected to the electrodes through high precision resistors. Measurements have demonstrated a good uniformity and a good linearity though small distortions have been identified. Radiation tests with both neutrons and gammas have shown many shortcomings in the pulser and control logic. New developments to address these shortcomings are discussed.