DP83907

The DP83907 Twisted-Pair Enhanced Coaxial Network Interface Controller is a CMOS VLSI device designed for easy implementation of CSMA/CD local area networks. Unique to the DP83907 is the integration of the entire bus interface for PCAT ISA (Industry Standard Architecture) bus based systems. Hardware and software selectable options allow the DP83907's bus interface to be configured in the same manner as an NE2000 Architecture. All bus drivers  and control logic are integrated to reduce board cost and area.

Supported network interfaces include 10BASE5 or  10BASE2 Ethernet via an external transceiver connected to its AUl port, and Twisted-pair EthernetÉ (10BASE-T) using the on-board transceiver. The DP83907 provides the Ethernet Media Access Control (MAC), Encode-Decode (ENDEC) with an AUl interface, and 10BASE-T transceiver functions in accordance with the lEEE 802.3 standards.

The DP83907's integrated 10BASE-T transceiver fully complies with the IEEE standard. This functional block incorporates the receiver, transmitter, collision, heartbeat, loopback, jabber, and link integrity blocks as defined in the standard. The transceiver when combined with equalization resistors, transmit/receive filters, and pulse transformers provides a complete physical interface from the DP83907's ENDEC module and the twisted pair medium.

The integrated ENDEC module allows Manchester encoding and decoding via a differential transceiver and phase lock loop decoder at 10 Mbit/sec. Also included are a collision detect translator and diagnostic loopback capability. The ENDEC module interfaces directly to the transceiver module, and also provides a fully IEEE compliant AUI (Attachment Unit Interface) for connection to other media transceivers.

The Media Access Control function which is provided by the Network Interface Control module (NIC) provides simple and efficient packet transmission and reception control by means of off-board memory which can be accessed through an I/O port.

The DP83907 provides a comprehensive solution for 10BASE-T IEEE 802.3 networks. Due to the inherent constraints of CMOS processing, isolation is required at the AUI differential signal interface for 10BASE5 and 10BASE2 applications.