  The upgrade of ATLAS Liquid Argon Calorimeter (LAr) Phase-1 trigger requires
high-speed, low-latency data transmission to read out the Lar Trigger Digitizer
Board (LTDB). A dual-channel transmitter ASIC LOCx2 have been designed and
produced. In order to ensure all the LOCx2 chips behave properly, a Quality
Assurance needs to be conducted before assembly. The problem I was trying to
solve in this project is to yield a clock signal with continuously adjustable
frequency and phase offset to generate and control an eye diagram for the QA.
By configuring the registers of an any-frequency generator IC, Si5338, the
clock signal whose frequency range from 5MHz to 200 MHz have been properly
produced. For the purpose of further development, a C-language based DLL which
packs up the function of adjusting frequency and setting phase offset was
designed and built, and several evaluation was performed to ensure the
robustness of DLL.
