DS3253+ [Analog Devices]

The DS3251, DS3252, DS3253, and DS3254 are pin-compatible line interface units (LIUs) for DS3, E3, or STS-1 lines. Each LIU has independent receive and transmit paths with a built-in jitter attenuator. The receiver performs clock and data recovery from B3ZS/HDB3-coded AMI signals, monitors for loss of signal, and optionally decodes B3ZS/HDB3 to output data in binary or bipolar format. The transmitter accepts binary or bipolar data, optionally encodes B3ZS/HDB3, and drives standard waveforms onto 75Ω coaxial cable. The jitter attenuator can be placed in the receive or transmit path or disabled. An on-chip clock adapter generates all line-rate clocks from a single input clock. Control interfaces include 8-bit parallel, SPI, and hardware mode. The devices conform to telecommunications standards and require minimal external components.