FWLF1631Rxx DWDM SFP Product Specification – July 2013 F i n i s a r
Finisar Corporation Page 8
Rev C1, July 2013
IX. Serial Communication Protocol
All Finisar SFPs support the 2-wire serial communication protocol to provide module ID
information as outlined in the SFP MSA
1
. These SFPs use an Atmel AT24C01A 128 byte
E
2
PROM with an address of A0h. For details on interfacing with the E
2
PROM, see the
Atmel data sheet titled “AT24C01A/02/04/08/16 2-Wire Serial CMOS E
2
PROM.”
3
Finisar SFPs also support diagnostic features as described in Finisar Applications Note AN-
2030
4
and SFF-8472
5
, “Digital Diagnostic Monitoring Interface for Optical Transceivers”.
A controller IC that monitors system parameters such as laser current, module temperature,
transmitter power, and received power is accessible at address A2H. In addition, Finisar’s
DWDM SFPs provide extended set of ID information and diagnostic features as described
in the DWDM SFP MSA
6
.
I2C clock speed, digital diagnostic accuracy and digital diagnostic range can be found in the
table below. Values in the table represent the worst-case values over temperature, voltage,
and life.
Transceiver Case
Temperature
Measured on the top-side of
the module case
Transceiver Supply
Voltage
Transceiver Case
Temperature
Transceiver Supply
Voltage
