HFBR-5911LZ/ALZ Small Form Factor Optical Transceiver for Gigabit Ethernet (1.25 GBd) and iSCSI Data Sheet Description Features IEEE 802.3 Gigabit Ether net The HFBR-5911LZ/ALZ optical transceiver from Avago (1.25 Gbd) 1000BASE-SX compliant Technologies is designed for use in short-reach multi- I ndustr y standard small for m fac tor (SFF) pack age mode fiber optic (1000BASE-SX) links between Gigabit LC- duplex connec tor optical inter face Ethernet networking equipment. Interoperable with 850 nm Ver tical cavit y sur face emitting laser all equipment meeting the Gigabit Ethernet industry I nter nally ter minated and ac coupled data IO standard, it is compliant with the Small Form Factor Multi Ex tended operating temperature range (HFBR- Source Agreement and requires a 3.3 V dc power supply. 5911ALZ only) : The electrical interface follows the 2 x 5 format while the -10 to +85 C optical interface uses the LC-Duplex connector. Signal detec t T TL Related Products M aximum link lengths: 62.5/125 m fiber 275 m AFBR-5710LZ: 850 nm Small For m Fac tor Pluggable 50/125 m fiber 550 m optical transceiver for short reach Gigabit Ethernet Laser AEL Class 1 (eye safe) per : (1000BASE-SX) links US 21 CFR( J ) HDMP-1687: Q uad S erD es IC for Gigabit Ether net EN 60825-1 (+All) with 10 bit parallel interface and TTL clock input +3.3 V dc power supply HDMP-1685A: Q uad S erD es IC for Gigabit Ether net M anufac tured in ISO 9001 facilities with 5 bit parallel interface and DDR TTL clock input R oHS Compliant HDMP-1636A/46A: Single S erD es IC for Gigabit Eth- ernet and Fiber Channel Applications HDMP-1637A: Single S erD es IC with PECL R efClk Shor t-reach Gigabit Ether net links HDMP-1638: Single S erD es IC with PECL R efClk and H igh speed back plane interconnec ts Dual Serial I/O Switched back bones HDMP-2634: Single S erD es IC 2.5/1.25 Gigabit iSCSI applicationsOverview Tx Disable Avago Technologies HFBR-5911LZ/ALZ optical transceiver The HFBR-5911LZ/ALZ accepts a TTL transmit disable supports high-speed serial links over multimode optical control signal input which shuts down the transmitter. A fiber at signaling rates of up to 1.25 Gb/s. Compliant high signal implements this function while a low signal with the Small Form Factor (SFF) Multi Source Agreement allows normal transceiver operation. In the event of a (MSA) for 2 x 5 pin LC D uplex transceivers and IEEE 802.3 fault (e.g., eye safety circuit activated), cycling this control specification for Gigabit Ethernet (GbE) links (1000BASE- signal resets the module as depicted in Figure 5 page 12. SX), the part is interoperable and interchangeable with A pull-down resistor enables the laser if the line is not other conformant devices. Supported Gigabit Ethernet connected on the host board. link lengths are described in Table 1, but the transceiver Host systems should allow a 10 ms interval between suc- can also be used for other high-speed serial applications, cessive assertions of this control signal. such as iSCSI. Eye Safety Circuit The SFF package of the HFBR-5911LZ/ALZ allows design- ers of Gigabit Ethernet networking equipment to maxi- The HFBR-5911LZ/ALZ provides Class 1 eye safety by mize their use of available board space. The footprint design and has been tested for compliance with the of the HFBR-5911LZ/ALZ is significantly smaller than requirements listed in Table 11. The eye safety circuit those of other GbE transceivers formats - 25% smaller continuously monitors optical output power levels and than SFP cage assemblies, 30% smaller than traditional will disable the transmitter upon detecting an unsafe 1 x 9 transceivers and 70% smaller than GBIC rail as- condition. Such unsafe conditions can be due to inputs semblies. The HFBR-5911LZ/ALZ trace keep-out area is from the host board (V fluctuation, unbalanced code) CC less than 10% as large as that required by SFP transceiv- or faults within the transceiver. ers. For applications not requiring hot-pluggability, the Receiver Section HFBR-5911LZ/ALZ offers a more space-efficient package without the additional cost and complexity imposed by The receiver section includes the Receiver Optical Subassem- pluggable architecture. bly (ROSA) and the amplification/quantization circuitry. The ROSA, containing a PIN photodiode and custom transimped- Module Diagrams ance preamplifier, is located at the optical interface and mates The major functional components of the HFBR-5911LZ/ALZ with the LC optical connector. The ROSA output is fed to a are illustrated in Figure 2 page 9. The external configu - custom IC that provides post-amplicfi ation and quantization. ration of the transceiver is depicted in Figure 3 page 10 Signal Detect while the host board and front panel layouts defined by the SFF MSA are shown in Figure 4, page 11. The post-amplification/quantizer IC also includes transition detection circuitry that monitors the ac level of the incoming Transmitter Section optical signal and provides a TTL status signal to the host. An The transmitter section consists of the Transmitter Optical adequate optical input results in a high output while a low Subassembly (TOSA) and laser driver circuitry. The TOSA, Signal Detect output indicates an unusable optical input. The containing an 850 nm VCSEL (Vertical Cavity Surface Emit- Signal Detect thresholds are set so that a low output indicates ting Laser) light source, is located at the optical interface and a definite optical fault has occurred (e.g., disconnected or mates with the LC optical connector. The TOSA is driven by broken fiber connection to receiver, failed transmitter, etc.). a custom IC which uses the incoming differential PECL logic signals to modulate the laser diode drive current. This Tx laser driver circuit regulates the optical output power at a constant level provided that the incoming data pattern is dc balanced (8B10B code for example). 2