Am79C100

The Am79C100 Twisted-Pair Ethernet Transceiver Plus (TPEX Plus) is an integrated circuit that implements the
medium attachment unit (MAU) functions for the twisted-pair medium, as specified by the supplement to the IEEE 802.3 standard (Type 10BASE-T). This device provides the necessary electrical and functional interface between the IEEE 802.3 standard attachment unit interface (AUI) and the twisted-pair cable.

A network based on the 10BASE-T standard can use unshielded twisted-pair cables, providing an economical solution to networking by allowing the use of existing telephone wiring. The Am79C100 provides a minimal component count and a cost-effective solution to the design and implementation of 10BASE-T standard networks.

TPEX Plus provides twisted-pair driver and receiver circuits, including on-board transmit digital predistortion, receiver squelch, and an AUI port with pin-selectable SQE Test enable. Am79C100 provides a number of additional features, including Link Status indication with automatic twisted-pair receive polarity detection/ correction and indication; pin-selectable receive threshold programming for extended distance line lengths; and Receive Carrier Sense, Transmit Active and Collision Present indications. The device provides separate twisted-pair Link Status, Polarity Status, Receive, Transmit, and Collision outputs to drive LEDs directly.