PT Journal AU Real, D Calvo, D Zornoza, JD Manzaneda, M TI White Rabbit Expansion Board: Design, Architecture, and Signal Integrity Simulations SO Electronics JI Electronics PY 2023 BP 3394 - 16pp VL 12 IS 16 DI 10.3390/electronics12163394 LA English DE subnanosecond synchronization; White Rabbit; IEEE Std 1588-2019; virtual prototyping AB The White Rabbit protocol allows synchronization and communication via an optical link in an integrated, modular, and scalable manner. It provides a solution to those applications that have very demanding requirements in terms of synchronization. Field-programmable gate arrays are used to implement the protocol; additionally, special hardware is needed to provide the necessary clock signals used by the dual-mixer time difference for precise phase measurement. In the present work, an expansion board that allows for White Rabbit functionality is presented. The expansion board contains the oscillators required by the White Rabbit protocol, one running at 125 MHz and another at 124.922 MHZ. The architecture of this board includes two oscillator systems for tests and comparison. One is based on VCOs and another on crystal oscillators running at the desired frequencies. In addition, it incorporates a temperature sensor, from where the medium access control address is extracted, an electrically erasable programmable read-only memory, a pulse-per-second output, and a USB UART to access the White Rabbit IP core at the field-programmable gate array. Finally, to ensure the quality of the layout design and guarantee the level of synchronization desired, the results of the power and signal integrity simulations are also presented. ER