FBFM2112F897CSLJLS View Datasheet(PDF) - Intel

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Description

Manufacturer

FBFM2112F897CSLJLS

Intel® FM2112 24-Port 10G/1G Ethernet Switch Chip

Intel 

Intel® FM2112 24-Port 10G/1G Ethernet Switch Chip Data Sheet

3.1.2.1

3.1.2.2

3.1.2.3

The per-lane data-rate on the “8b” side is a factor of 8 greater, yielding

800 Mb/s to 3.2 Gb/s of actual data throughput, and on the “10b” side

this gives 1 Gb/s to 4 Gb/s of serial data per lane.

Compatibility

The SerDes interface is electrically compatible with the following

standards and specifications:

• 1G Ethernet

— IEEE 802.3ad, 1000BASE-CX

— SGMII

• 10G Ethernet

— IEEE 802.3ae, XGXS (XAUI)

— IEEE 802.3ak, 10GBASE-CX4

• Ethernet at a user-configured rate

— As an example, 2.5G Ethernet through the use of a single SerDes pair

Phase-Locked Loop (PLL) and Reference Frequency

The electrical specifications for the clock are described in Section 3.6.1.

Using a divide-by-5 ratio, the PLL has a frequency of operation from

500 MHz to 2 GHz. The data is double pumped off of the voltage-

controlled oscillator. The PLL does not need to support 1G operation

from the same clock source that supports 10G operation as that feature

is achieved through the use of the second off-chip reference clock.

Transmitter Drive Current

The nominal SerDes output driver current is set to 20 mA by an

external resistor of 1.2KW tied between the Reference resistor pad.

Connect a 1.2KΩ resistor from each RREF pad to 1.2V VDDX or a 1.0KΩ

resistor from each RREF to 1.0V VDDX. Provides a reference current for

the driver and equalization circuits. pins (1 per port) and VDDX. A new

nominal output current value of 10 mA or 28 mA may be set

individually for each lane in each port by setting the corresponding

High Drive and Low Drive bits in the SERDES_CNTL_2 register (see

Table 133 for details).

The output currents may be further modified from this nominal value

for each of the 4 lanes in each port by setting the corresponding DTX

bits in the SERDES_CNTL_1 register (see Table 130 for details). Using

these bits the current can be set from 60% to 135% of the established

nominal value.

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