FWLF1634Ryxx DWDM SFP Preliminary Product Specification – February 2009
F i n i s a r
IX. Serial Communication Protocol
All Finisar SFPs support the 2-wire serial communication protocol to provide module ID
information as outlined in the SFP MSA1. These SFPs use an Atmel AT24C01A 128 byte
E2PROM with an address of A0h. For details on interfacing with the E2PROM, see the
Atmel data sheet titled “AT24C01A/02/04/08/16 2-Wire Serial CMOS E2PROM.”3
Finisar SFPs also support diagnostic features as described in Finisar Applications Note AN-
20304 and SFF-84725, “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 MSA6.
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.
Parameter
I2C Clock Speed
Accuracy
Transceiver Case
Temperature
Transceiver Supply
Voltage
Symbol Min Typ Max Units Notes/Conditions
0
100,000
Hz
°C
%
Bus can be driven blind
DDTemperature -10
+10
Measured on the top-side of
the module case
DDVoltage
-3
+3
Tx Bias Current
Tx Output Power
Received Average
Power
DDBias
DDTxPower
DDRxPower
-10
-2
-2
+10
+2
+2
%
dB
dB
Range
Transceiver Case
Temperature
Transceiver Supply
Voltage
DDTemperature -40
85
°C
V
DDVoltage
3.0
4.0
Tx Bias Current
Tx Output Power
Received Average
Power
DDBias
DDTxPower
DDRxPower
0
-5
-30
90
+10
-7
mA
dBm
dBm
Finisar Corporation
Rev C2, Feb.2009
PRELIMINARY
Page 8
FINISAR [ FINISAR CORPORATION. ]
