AFBR-57R6AEZ Avago Technologies US Inc., AFBR-57R6AEZ Datasheet - Page 3

• Manufacturer Part Number: AFBR-57R6AEZ
• Description: Fiber Optic Transmitters, Receivers, Transceivers Transceiver
• Manufacturer: Avago Technologies US Inc.
• Series: -r

Specifications of AFBR-57R6AEZ

• Product: Transceiver
• Data Rate: 4.25 GBd, 2.125 GBd, 1.0625 GBd, 1.25 GBd
• Wavelength: 860 nm (Max)
• Maximum Rise Time: 0.09 ns/0.15 ns
• Maximum Fall Time: 0.09 ns/0.15 ns
• Pulse Width Distortion: 0.06 ns (Max)/0.062 ns (Max)
• Maximum Output Current: 300 mA
• Operating Supply Voltage: 2.97 V to 3.63 V
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 10 C
• Package / Case: SFP
• Mounting Type: SFP
• Voltage - Supply: 2.97 V ~ 3.63 V
• Connector Type: LC Duplex
• Applications: Ethernet
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: Multimode Fiber
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

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Figure 1. Transceiver functional diagram
Transmitter Section
The transmitter section includes the Transmitter Opti-
cal SubAssembly (TOSA) and laser driver circuitry. The
TOSA, containing an 850 nm VCSEL (Vertical Cavity Sur-
face Emitting Laser) light source, is located at the optical
interface and mates with the LC optical connector. The
TOSA is driven by a custom IC which uses the incoming
differential high speed logic signal to modulate the la-
ser diode driver current. This Tx laser driver circuit regu-
lates the optical power at a constant level provided the
incoming data pattern is dc balanced (8B/10B code, for
example).
Transmit Disable (Tx_Disable)
The AFBR-57R6AEZ accepts a TTL and CMOS compat-
ible transmit disable control signal input (pin 3) which
shuts down the transmitter optical output. A high signal
implements this function while a low signal allows nor-
mal transceiver operation. In the event of a fault (e.g. eye
safety circuit activated), cycling this control signal resets
the module as depicted in Figure 4. An internal pull up
resistor disables the transceiver transmitter until the host
pulls the input low. Host systems should allow a 10 ms
interval between successive assertions of this control
signal. Tx_Disable can also be asserted via the two-wire
serial interface (address A2h, byte 110, bit 6) and moni-
tored (address A2h, byte 110, bit 7).
The contents of A2h, byte 110, bit 6 are logic OR’d with
hardware Tx_Disable (pin 3) to control transmitter opera-
tion.
OPTICAL INTERFACE
LIGHT FROM FIBER
LIGHT TO FIBER
RECEIVER
TRANSMITTER
PHOTO-DETECTOR
VCSEL
CONTROLLER & MEMORY
AMPLIFICATION
& QUANTIZATION
Transmit Fault (Tx_Fault)
A catastrophic laser fault will activate the transmitter sig-
nal, TX_FAULT, and disable the laser. This signal is an open
collector output (pull-up required on the host board). A
low signal indicates normal laser operation and a high
signal indicates a fault. The TX_FAULT will be latched high
when a laser fault occurs and is cleared by toggling the
TX_DISABLE input or power cycling the transceiver. The
transmitter fault condition can also be monitored via the
two-wire serial interface (address A2, byte 110, bit 2).
Eye Safety Circuit
The AFBR-57R6AEZ provides Class 1 (single fault tolerant)
eye safety by design and has been tested for compliance
with the requirements listed in Table 1. The eye safety
circuit continuously monitors the optical output power
level and will disable the transmitter upon detecting an
unsafe condition beyond the scope of Class 1 certifica-
tion. Such unsafe conditions can be due to inputs from
the host board (Vcc fluctuation, unbalanced code) or a
fault within the transceiver.
CIRCUITRY
DRIVER &
SAFETY
LASER
ELECTRICAL INTERFACE
RD+ (RECEIVE DATA)
RDÐ (RECEIVE DATA)
Rx LOSS OF SIGNAL
RATE SELECT
MOD-DEF2 (SDA)
MOD-DEF1 (SCL)
MOD-DEF0
TX_DISABLE
TD+ (TRANSMIT DATA)
TDÐ (TRANSMIT DATA)
TX_FAULT