Agilent HFBR/HFCT-5208M 1 x 9 Fiber Optic Transceivers for 622 Mb/s ATM/SONET/SDH Applications
Data Sheet
Features • Performance HFBR-5208M: Links of 500 m with 62.5/125 µm multimode fiber (MMF) from 155-622 Mb/s HFCT-5208M: Links of 15 km with 9/125 µm single-mode fiber (SMF) • Compliant with ATM forum 622.08 Mb/s physical layer specification (AF-PHY-0046.000) • Compliant with ANSI broadband ISDN - physical layer specification T1.646-1995 and T1.646a-1997 • HFBR-5208M is compliant with ANSI network to customer installation interfaces synchronous optical NETwork (SONET) physical media dependent specification: multimode fiber T1.416.01-1998 • HFCT-5208M is compliant to the intermediate SONET OC12/SDH STM(S4.1) specifications • Industry-standard multi-sourced 1 x 9 mezzanine package style • Single +5 V power supply operation and PECL logic interfaces • Wave solder and aqueous wash process compatible • Unconditionally eye safe laser IEC 825/CDRH Class 1 compliant
Description General The HFBR-5208M (multimode transceiver) and HFCT-5208M (single-mode transceiver) from Agilent allow the system designer to implement a range of solutions for ATM/SONET STS-12/SDH STM-4 applications. The overall Agilent transceiver consists of three sections: the transmitter and receiver optical subassemblies, an electrical subassembly and the mezzanine package housing which incorporates a duplex SC connector receptacle. Transmitter Section The transmitter section of the HFBR-5208M consists of a 1300 nm LED in an optical subassembly (OSA) which mates to the multimode fiber cable. The HFCT-5208M incorporates a 1300 nm Fabry Perot (FP) laser in the optical subassembly. In addition, this package has been designed to be compliant with IEC 825 eye-safety requirements under any single fault condition. The OSA’s are driven by a custom, silicon bipolar IC which converts differential PECL logic signals (ECL referenced to a +5 V supply) into an analog LED/laser drive current.
Applications HFBR-5208M: • General purpose low-cost MMF links at 155 to 650 Mb/s • ATM 622 Mb/s MMF links from switch-to-switch or switch-toserver in the end-user premise • Private MMF interconnections at 622 Mb/s SONET STS-12/SDH STM-4 rate HFCT-5208M: • ATM 622 Mb/s SMF links from switch-to-switch or switch-toserver in the end-user premise • Private SMF interconnections at 622 Mb/s SONET STS-12/SDH STM-4 rate 622 Mb/s Product Family HFCT-5218M: • 1300 nm laser-based transceiver in 1 x 9 package for links of 40 km with single-mode fiber cables
Receiver Section The receiver contains an InGaAs PIN photodiode mounted together with a custom, silicon bipolar transimpedance preamplifier IC in an OSA. This OSA is mated to a custom, silicon bipolar circuit providing post amplification and quantization and optical signal detection. The custom, silicon bipolar circuit includes a Signal Detect circuit which provides a PECL logic high state output upon detection of a usable input optical signal level. This single-ended PECL output is designed to drive a standard PECL input through normal 50 W PECL load. Applications Information Typical BER Performance of HFBR-5208M Receiver versus Input Optical Power Level The HFBR/HFCT-5208M transceiver can be operated at Bit-Error-Ratio conditions other than the required BER = 1 x 10-10 of the 622 MBd ATM Forum 622.08 Mb/s Physical Layer Standard and the ANSI T1.646a. The typical trade-off of BER versus Relative Input Optical Power is shown in Figure 1. The Relative Input Optical Power in dB is referenced to the Input Optical Power parameter value in the Receiver Optical Characteristics table. For better BER condition than 1 x 10-10, more input signal is needed (+dB). For example, to operate the
10-2 10-3 10-4 10-5 10-6 10-7 10-8 10-9 10-10 10-11 10-12 10-13 10-14 10-15 BIT ERROR RATIO
LINEAR EXTRAPOLATION OF 10-4 THROUGH 10 -7 DATA ACTUAL DATA
HFBR-5208M at a BER of 1 x 10-12, the receiver will require an input signal approximately 0.6 dB higher than the -26 dBm level required for 1 x 10-10 operation, i.e. -25.4 dBm. An informative graph of a typical, short fiber transceiver link performance can be seen in Figure 2. This figure is useful for designing short reach links with time-based jitter requirements. This figure indicates Relative Input Optical Power versus Sampling Time Position within the receiver output data eye-opening. The given curves are at a constant biterror-ratio (BER) of 10-10 for four different signaling rates, 155 MBd, 311 MBd, 622 MBd and 650 MBd. These curves, called “tub” diagrams for their shape, show the amount of data eye-opening time-width for various receiver input optical power levels. A wider data eye-opening provides more time for the clock recovery circuit to operate within without creating errors. The deeper the tub is indicates less input optical power is needed to operate the receiver at the same BER condition. Generally, the wider and deeper the tub is the better. The Relative Input Optical Power amount (dB) is referenced to the absolute level (dBm avg.) given in the Receiver Optical Characteristics table. The 0 ns sampling time position for this Figure 2 refers to the center of the Baud interval for the particular signaling rate. The Baud interval is the reciprocal of the signaling rate in MBd. For example, at 622 MBd the Baud interval is 1.61 ns, at 155 MBd the Baud interval is 6.45 ns. Test conditions for this tub diagram are listed in Figure 2. The HFBR/HFCT-5208M receiver input optical power requirements vary slightly over the signaling rate range of 20 MBd to 700 MBd for a constant bit-error-ratio (BER) of 10-10 condition. Figure 3 illustrates the typical receiver
relative input optical power varies by
