Am79761

The Am79761 Gigabit Ethernet Physical Layer Serializer/Deserializer (GigaPHY-SD) device is a 1.25 Gbps Ethernet Transceiver optimized for Gigabit Ethernet/1000BASE-X applications. It implements the Physical Medium Attachment (PMA) layer for a single port.

The GigaPHY-SD device can interface to fiber-optic media to support 1000BASE-LX and 1000BASE-SX applications and can interface to copper coax to support 1000BASE-CX applications.

The functions performed by Am79761 include serializing the 8B/10B 10-bit data for transmission, deserializing received code groups, recovering the clock from the incoming data stream, and word synchronization.

When transmitting, the Am79761device receives 10-bit 8B/10B code groups at 125 million code groups per second. It then serializes the parallel data stream,  adding a reference clock, and transmits it through the PECL drivers.

When receiving, the Am79761device receives the PECL data stream from the network. It then recovers the clock from the data stream, deserializes the data stream into a 10-bit code group, and transmits it to the Physical Coding Sublayer (PCS) logic above. Optionally, it detects comma characters used to align the incoming word