AFBR-5803AQZ Ver la hoja de datos (PDF) - Avago Technologies
Número de pieza
componentes Descripción
Fabricante
AFBR-5803AQZ
Avago Technologies
AFBR-5803AQZ Datasheet PDF : 16 Pages
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12. The Extinction Ratio is a measure of the modulation depth of the optical signal. The data “0” output optical power is compared to the data “1”
peak output optical power and expressed as a percentage. With the transmitter driven by a HALT Line State (12.5 MHz square-wave) signal,
the average optical power is measured. The data “1” peak power is then calculated by adding 3 dB to the measured average optical power.
The data “0” output optical power is found by measuring the optical power when the transmitter is driven by a logic “0” input. The extinction
ratio is the ratio of the optical power at the “0” level compared to the optical power at the “1” level expressed as a percentage or in decibels.
13. The transmitter provides compliance with the need for Transmit_Disable commands from the FDDI SMT layer by providing an Output Optical
Power level of < ‑45 dBm average in response to a logic “0” input. This specification applies to either 62.5/125 µm or 50/125 µm fiber cables.
14. This parameter complies with the FDDI PMD requirements for the trade-offs between center wavelength, spectral width, and rise/fall times
shown in Figure 9.
15. This parameter complies with the optical pulse envelope from the FDDI PMD shown in Figure 10. The optical rise and fall times are measured
from 10% to 90% when the transmitter is driven by the FDDI HALT Line State (12.5 MHz square-wave) input signal.
16. Duty Cycle Distortion contributed by the transmitter is measured at a 50% threshold using an IDLE Line State, 125 MBd
(62.5 MHz square-wave), input signal. See Application Information - Transceiver Jitter Performance Section of this data sheet for further de-
tails.
17. Data Dependent Jitter contributed by the transmitter is specified with the FDDI test pattern described in FDDI PMD Annex A.5. See Applica
tion Information - Transceiver Jitter Performance Section of this data sheet for further details.
18. Random Jitter contributed by the transmitter is specified with an IDLE Line State, 125 MBd (62.5 MHz square-wave), input signal. See Applica-
tion Information - Transceiver Jitter Performance Section of this data sheet for further details.
19. This specification is intended to indicate the performance of the receiver section of the transceiver when Input Optical Power signal char-
acteristics are present per the following definitions. The Input Optical Power dynamic range from the minimum level (with a window time-
width) to the maximum level is the range over which the receiver is guaranteed to provide output data with a Bit Error Ratio (BER) better than
or equal to 2.5 x 10-10.
• At the Beginning of Life (BOL)
• Over the specified operating temperature and voltage ranges
• Input symbol pattern is the FDDI test pattern defined in FDDI PMD Annex A.5 with 4B/5B NRZI encoded data that contains a duty cycle
base-line wander effect of 50 kHz. This sequence causes a near worst case condition for inter-symbol interference.
• Receiver data window time-width is
2.13 ns or greater and centered at
mid-symbol. This worst case window time-width is the minimum allowed
eye-opening presented to the FDDI PHY PM._Data indication input (PHY input) per the example in FDDI PMD Annex E. This minimum win-
dow time-width of 2.13 ns is based upon the worst case FDDI PMD Active Input Interface optical conditions for peak-to-peak DCD (1.0 ns),
DDJ (1.2 ns) and RJ (0.76 ns) presented to the receiver.
To test a receiver with the worst case FDDI PMD Active Input jitter condition requires exacting control over DCD, DDJ and RJ jitter compo
nents that is difficult to implement with production test equipment. The receiver can be equivalently tested to the worst case FDDI PMD
input jitter conditions and meet the minimum output data window time-width of 2.13 ns. This is accomplished by using a nearly ideal input
optical signal (no DCD, insignificant DDJ and RJ) and measuring for a wider window time-width of 4.6 ns. This is possible due to the cumula
tive effect of jitter components through their superposition (DCD and DDJ are directly additive and RJ components are rms additive). Specifi-
cally, when a nearly ideal input optical test signal is used and the maximum receiver peak-to-peak jitter contributions of DCD (0.4 ns), DDJ
(1.0 ns), and RJ (2.14 ns) exist, the minimum window time-width becomes 8.0 ns -0.4 ns - 1.0 ns - 2.14 ns = 4.46 ns, or conservatively 4.6 ns.
This wider window time-width of 4.6 ns guarantees the FDDI PMD Annex E minimum window time-width of 2.13 ns under worst case input
jitter conditions to the Avago Technologies receiver.
• Transmitter operating with an IDLE Line State pattern, 125 MBd (62.5 MHz square-wave), input signal to simulate any cross-talk present
between the transmitter and receiver sections of the transceiver.
20. All conditions of Note 19 apply except that the measurement is made at the center of the symbol with no window time-width.
21. This value is measured during the transition from low to high levels of input optical power.
22. The Signal Detect output shall be asserted within 100 µs after a step increase of the Input Optical Power. The step will be from a low Input
Optical Power, -45 dBm, into the range between greater than PA, and
-14 dBm. The BER of the receiver output will be 10-2 or better during the time, LS_Max (15 µs) after Signal Detect has been asserted. See Fig-
ure 12 for more information.
23. This value is measured during the transition from high to low levels of input optical power. The maximum value will occur when the input
optical power is either -45 dBm average or when the input optical power yields a BER of 10-2 or larger, whichever power is higher.
24. Signal detect output shall be de-asserted within 350 µs after a step decrease in the Input Optical Power from a level which is the lower of; ‑31
dBm or PD + 4 dB (PD is the power level at which signal detect was de-asserted), to a power level of ‑45 dBm or less. This step decrease will
have occurred in less than 8 ns. The receiver output will have a BER of 10-2 or better for a period of 12 µs or until signal detect is de-asserted.
The input data stream is the Quiet Line State. Also, signal detect will be de-asserted within a maximum of 350 µs after the BER of the receiver
output degrades above 10-2 for an input optical data stream that decays with a negative ramp function instead of a step function. See Figure
12 for more information.
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