General Description
The VSC7185 is a full-speed quad Gigabit Ethernet and Fibre Channel Transceiver IC. 8B/10B encoded (or equivalent scheme) transmit characters are serialized onto high-speed differential outputs (SOi+/-) at speeds up to 1.36Gb/s. Each of the four transmitters has a 5-bit wide parallel input bus. Parallel data is latched in by an internal clock running at up to 272MHz (2x the rate of the external common Transmit Byte Clock). Transmit data must be presented synchronously with the common transmit byte clock. Each receiver samples the serial receive data (SIi+/-), recovers the clock and data, deserializes it into 5-bit receive half-characters, outputs a recovered 2x or 1x clock and detects “Comma” characters. The VSC7185 contains on-chip PLL circuitry for synthesis of the baud-rate transmit clock and extraction of the clocks from the received serial streams.

FEATUREs
• Four Complete Transceiver Functions in a Single Integrated Circuit
• SSTL-2 Compatible Parallel Data and Clocks
• 1.05Gb/s to 1.36Gb/s Operation per Channel
• Common Transmit Byte Clock
• TTL or PECL Reference Clock Input
• Per-Channel 1/10th Baud Rate Recovered Clocks and Comma Detect Outputs
• Common Comma Detect Enable Input
• Common Serial / Parallel Loopback Controls
• Cable Equalization in Receivers
• JTAG Access Port
• 3.3V Power Supply, 2.5W Dissipation
• 208 pin, 23mm BGA Package