Dallas Semiconductor's DS317x is a family of single-chip, multiport T3/E3 transceivers that combine framers and line interface units (LIUs). This single-chip transceiver (SCT) family consists of the DS3174 (quad), DS3173 (triple), DS3172 (dual), and DS3171 (single) SCTs. Plus, it includes a tiny single-port DS3170. By providing a fully integrated LIU and framer that require no external components, the DS317x family minimizes design time, component cost and board space.

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The DS3171-DS3174 devices are pin- and software-compatible with each other for easy port-density migration from a single PCB design. Additionally, they are pin- and software-compatible with the DS318x family of ATM/Packet PHYs with LIUs for future upgrades to ATM and/or packet support.

The DS317x transceiver family includes an integrated clock rate adapter to generate the required 44.736MHz (DS3), 34.368MHz (E3), and/or 52MHz for arbitrary framing protocol up to 52 Mbps, from a single DS3, E3, or STS-1 input reference.

All ports are independently configurable for DS3/E3. The devices have a built-in jitter attenuator for each port that can be placed either in the receive or the transmit path. Each port can be disabled to reduce power. The DS317x parts have on-chip bit error rate testers (BERTs) for diagnostic testing of each port. The parts support loop timing modes. Packaged in a tiny 11 mm, 100-pin CSBGA, the DS3170 is the smallest T3/E3 SCT in the industry, claims Maxim. It also consumes the lowest power(500 mW). The DS3170 has all the capabilities of the DS317x family, but gives the user the additional option of using the SPI serial communications interface. The DS3170 is also available in a 14 mm LQFP package.

The DS3171-DS3174 SCTs are available in small, high-density 27 mm, TE-CSBGA packages. All devices are available in commercial and industrial operating temperature ranges. Prices start at $115 for the DS3174 and $27 for the DS3170 (1000-up, FOB USA). Evaluation kits are available.