V23838-M305-M56 Datasheet, PDF (6/21 Pages) Infineon Technologies AG – SFP-Small Form-factor Pluggable 1.25 Gigabit Ethernet 2.125/1.0625 Gbit/s Fibre Channel Multimode 850 nm Transceiver with LC™ Connector

V23838-M305-M56
Description
The receiver component converts the optical serial data into CML compatible electrical
data (RD+ and RD–). The Loss Of Signal (LOS) shows whether an optical signal is
present.
The transmitter converts CML compatible electrical serial data (TD+ and TD–) into
optical serial data. Data lines are differentially 100 Ω terminated.
The transmitter contains a laser driver circuit that drives the modulation and bias current
of the laser diode. The currents are controlled by a power control circuit to guarantee
constant output power of the laser over temperature and aging. The power control uses
the output of the monitor PIN diode (mechanically built into the laser coupling unit) as a
controlling signal, to prevent the laser power from exceeding the operating limits.
Single fault condition is ensured by means of an integrated automatic shutdown circuit
that disables the laser when it detects laser fault to guarantee the laser Eye Safety.
The transceiver contains a supervisory circuit to control the power supply. This circuit
makes an internal reset signal whenever the supply voltage drops below the reset
threshold. It keeps the reset signal active for at least 140 milliseconds after the voltage
has risen above the reset threshold. During this time the laser is inactive.
A low signal on TxDis enables transmitter. If TxDis is high or not connected the
transmitter is disabled.
The serial ID interface defines a 256 byte memory map in EEPROM, accessible over a
2 wire, serial interface at the 8 bit address 1010000X (A0h).
Data Sheet
6
2004-06-23