Single Gain Radiation Tolerant LHC Beam Loss Acquisition Card

The beam loss monitoring system is one of the most critical elements for the protection of the LHC. It must prevent the super conducting magnets from quenches and the machine components from damages, caused by beam losses. Ionization chambers and secondary emission based detectors are used at several locations around the ring. The sensors are producing a signal current, which is related to the losses. This current will be measured by a tunnel card, which acquires, digitizes and transmits the data via an optical link to the surface electronic. The usage of the system, for protection and tuning of the LHC and the scale of the LHC, imposed exceptional specifications of the dynamic range and radiation tolerance. The input dynamic allows measurements between 10pA and 1mA and its protected to high pulse of 1.5kV and its corresponding current. To cover this range, a current to frequency converter in combination with an ADC is used. The integrator output voltage is measured with an ADC to improve the resolution. The radiation tolerance required the adaption of conceptional design and a stringent selection of the components