The optical Synchronization and Link Board project, oSLB

The calorimeter trigger synchronization of the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC) uses a synchronization method implemented in the synchronization and link board (SLB). These boards allow the synchronization of electromagnetic and hadronic trigger primitives at the LHC frequency (40.08 MHz) and its transmission to the Regional Calorimeter Trigger. The upgrade of the Calorimeter Trigger system dictates the use of input optical links at a rate of 4.8 Gb/s. In this paper we present the design options and technological choices for the optical part of new optical Synchronization and Link Boards (oSLB).