Clock and data recovery methods for the readout control unit 2 in ALICE TPC

The present ALICE TPC readout electronics consists of 4356 Front End Cards that are read out and controlled by a total of 216 Readout Control Units (RCUs). The RCU communicates with all sub-systems, in particular with the Timing, Trigger and Control (TTC) system, which provides each RCU with the 40.08 MHz LHC clock, which is used as a system and sampling clock in TPC readout electronics. The LHC clock and trigger data are sent over the TTC fiber using 80 Mb/s Time Division Multiplexed BiPhase Mark encoded signals. It is important to have a radiation tolerant solution to recover the clock with low jitter and with a predefined phase-offset to the LHC input clock. Presently, this is handled by the TTC receiver (TTCrx) ASIC sitting on the RCU.