TMS38054

    The TMS38054 ring interface device and its associated external passive components form a full-duplex electrical interface to the token ring. Coupling the TMS38054 with one of the TMS380 family of commprocessors forms a highly integrated token-ring LAN adapter compatible with the ISO/IEC IEEE Std 802.5:1992 token-ring access method and physical-layer specifications.

    The TMS38054 operates at the IEEE-standard 16-Mbps and 4-Mbps data rates. The token-ring data stream is received by the TMS38054 and phase aligned using an on-chip phase-locked loop (PLL). The recovered clock and data are passed to the TI380C2x single-chip token-ring commprocessor's protocol-handling circuits for serial-to-parallel conversion and data processing. On transmit, the TMS380C2x provides a differential signal that the TMS38054 converts to analog levels for transmission on the media. A watchdog timer also is included to provide fail-safe deinsertion from the ring in the event of a station failure. The phase-detector gain is constant for all valid differential Manchester data that provide increased margin for unshielded twisted-pair applications.

    The TMS38054 is available in a 44-lead plastic chip carrier. The TMS38054 is characterized for operation from 0 to 70 with case temperature maintained at or below 99