Beyond the power rails and high-speed serial data lines, only a few auxiliary signals are needed for a functional UFS system.
UFS 3.1 supports up to two lanes for data transfer. Each lane consists of a differential pair: DIN_t / DIN_c: Data Input (Receive) pair from the host. DOUT_t / DOUT_c: Data Output (Transmit) pair to the host. Full Duplex ufs 3.1 pinout
