DAQ electronics for BOREXINO experiment

In this document we present the design and the implementation of an 8 chann els VME board with the following functionalities (for each channel): Dual threshold discriminator Time to Digital Converter with resolution better than 500 psec Dual sampling 8 bit Analog to Digital Converter The unit is controlled by a Digital Signal Processor. The DSP is used to co llect data in order to have maximum flexibility and efficiency. There is also the first stage of the trigger logic: the board outputs the n umber of photomultiplier fired in a time window of 50 nsec. Another level of trigger logic is implemented at crate level on a dedicated unit which gives the number of PMT fired on a crate basis.