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Installation
The AFCT-57R5ATPZ can be installed in any SFF-8074i
compliant Small Form Pluggable (SFP) port regardless of
host equipment operating status. The AFCT-57R5ATPZ is
hot-pluggable, allowing the module to be installed while
the host system is operating and on-line. Upon insertion,
the transceiver housing makes initial contact with the
host board SFP cage, mitigating potential damage due
to Electro-Static Discharge (ESD).
Digital Diagnostic Interface and Serial Identi cation
The 2-wire serial interface is based on ATMEL AT24C01A
series EEPROM protocol and signaling detail. Conventional
SFP EEPROM memory, bytes 0-255 at memory address
0xA0, is organized in compliance with SFF-8074i. New
digital diagnostic information, bytes 0-255 at memory
address 0xA2, is compliant to SFF-8472. The new diag-
nostic information provides the opportunity for Predictive
Failure Identi cation, Compliance Prediction, Fault Isola-
tion and Component Monitoring.
The I2C accessible memory page address 0xB0 is used
internally by SFP for the test and diagnostic purposes
and it is reserved.
Predictive Failure Identi cation
The AFCT-57R5ATPZ predictive failure feature allows a
host to identify potential link problems before system per-
formance is impacted. Prior identi cation of link problems
enables a host to service an application via “fail over” to a
redundant link or replace a suspect device, main taining
system uptime in the process. For applications where
ultra-high system uptime is required, a digital SFP provides
a means to monitor two real-time laser metrics associated
with observing laser degradation and predicting failure:
average laser bias current (Tx_Bias) and average laser
optical power (Tx_Power).
Compliance Prediction
Compliance prediction is the ability to determine if an
optical transceiver is operating within its operating and
environmental requirements. AFCT-57R5ATPZ devices
provide real-time access to transceiver internal supply
voltage and temperature, allowing a host to identify po-
tential component compliance issues. Received optical
power is also available to assess compliance of a cable
plant and remote transmitter. When operating out of
requirements, the link cannot guarantee error free trans-
mission.
Fault Isolation
The fault isolation feature allows a host to quickly pinpoint
the location of a link failure, minimizing downtime. For
optical links, the ability to identify a fault at a local device,
remote device or cable plant is crucial to speeding service
of an installation. AFCT-57R5ATPZ real-time monitors of
Tx_Bias, Tx_Power, Vcc, Temperature and Rx_Power can be
used to assess local transceiver current operating condi-
tions. In addition, status ags Tx_Disable and Rx Loss of
Signal (LOS) are mirrored in memory and available via the
two-wire serial interface.
Component Monitoring
Component evaluation is a more casual use of the AFCT-
57R5ATPZ real-time monitors of Tx_Bias, Tx_Power, Vcc,
Temperature and Rx_Power. Potential uses are as debug-
ging aids for system installation and design, and transceiv-
er parametric evaluation for factory or eld quali cation.
For example, temperature per module can be observed in
high density applications to facilitate thermal evaluation
of blades, PCI cards and systems.
