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Fiber Optics
V23816-N1018-C/L312, 3.3V, 4-Line LVDS Parallel 2.5GBd Transp.OC-48 SONET/SDH SR, 2km
8
Transmitter Electro-Optical Characteristics
Notes
1. The laser driver contains a control circuit, which regulates the aver-
age optical output power. Nominal output power is factory set to be
within the specified range.
2. The Eye Diagram is compliant with Bellcore GR-253 and ITU-T G.957
Eye Mask specifications.
3. J itter Generation is defined as the amount of jitter on the TX Optical
Output, when there is no or minimum jitter on the TX electrical
inputs. J itter Generation is compliant with GR-253 and ITU-T G.958
specifications, when measured using a 12 KHz - 20 MHz filter, and
with a jitter level on the REFCLKP/N input which is less than the
level specified in
”
AC Electrical Characteristics - Transmitter
”
.
4. If the +3.3 V power supply drops below the specified level, the laser
bias and modulation currents will be held disabled until the supply
voltage rises above threshold and after the Power On Delay Time
period.
5. A fault, such as high laser bias current or high average power, which
lasts longer than the specified Fault Delay time, will cause the trans-
mitter to be disabled. The fault can be cleared by cycling of DC
power, or by strobing the RESET_L input.
Receiver Electro-Optical Characteristics
Notes
1. Average RX power for a 1x10
–
10
BER, and using a PRBS pattern of
2
23
–
1 length with 72 zeros and 72 ones inserted, as per ITU-T
G.958.
2. J itter Tolerance is defined as the amount of jitter applied to the RX
optical input that the receiver will tolerate without producing bit
errors. The minimum required J itter Tolerance for a 1 dB power pen-
alty is defined to be 15 UI from 10 Hz to 600 Hz, 1.5 UI from 6 KHz to
100 KHz, and 0.15 UI from 1 MHz onwards, per Bellcore GR-253.
3. J itter Transfer is defined as the ratio of TX Output J itter to RX Input
J itter, when the transponder is operated in electrical loopback mode
(RX electrical outputs looped back into TX electrical inputs). J itter
Transfer is specified to be less than 0.1 dB up to 2 MHz, and drop-
ping at
–
20 dB/Decade after that point, per ITU-T G.958 and Bellcore
GR-253.
4. The RX_LOS output is an active high LVTTL output, which is set
HIGH if there is a loss of RX optical signal input (LOS), A decrease in
optical input power below the assert level will cause the RX_LOS
Parameter
Nominal Center Wave-
length
Range Of Center Wave-
lengths
Symbol
TX
λ
NOM
1310
Min.
Typ.
Max.
Units
nm
TX
λ
MIN
-
λ
MAX
TX
λ
RMS
TX P
AVG
1260
1360
Spectral Bandwidth
5
nm,
rms
Average Output
Power
(1)
–
11
–
4
–
3
dBm
Extinction Ratio
Output Rise Time
20%-80%
Output Fall Time
80%-20%
Eye Diagram
(2)
TX ER
TX T
R
8.2
14
100
dB
ps
200
TX T
F
175
250
TX ED
TX J itter Generation,
rms
(3)
TX
J
GEN rms
TX
J
GEN p-p
TX V
TH
0.007
0.01
UI
rms
TX J itter Generation,
p-p
(3)
0.075
0.1
UI p-p
Reset Threshold for
V
CC
(4)
Power On Delay for
V
CC
(4)
Fault Delay
(5)
2.2
2.95
V
TX T
POD
20
ms
TX
T
FAULT
TX I
BIAS
20
TX Bias Monitor switch-
ing threshold
60
mA
Parameter
Nominal Center
Wavelength
Sensitivity (Average
Power)
(1)
Symbol
RX
λ
NOM
Min.
Typ.
1310
Max.
Units
nm
RX P
SENS
–
25
–
18
dBm
Overload (Average
Power)
(1)
RX P
OL
–
3
Optical Return Loss
RX J itter Tolerance
(2)
RX-to-TX J itter Trans-
fer
(3)
RX RL
27
dB
RX J
TOL
RX-TX J
XFR
Optical Path Penalty
RX P
PEN
RX F
CAPT
1.0
dB
Clock Recovery Cap-
ture Frequency
Range
(5)
±
200
ppm
Clock Recovery Ac-
quisition Lock Time
RX T
LOCK
32
250
μ
s
RX_LOS Output As-
sert relative To RX
Optical Input Power
(4)
RX_
LOS
ASSERT
–
30
–
25
dBm
RX_LOSYNC Output
Assert relative to RX
input frequency
(5)
RX_
LOSYNC
AS-
SERT
RX_
LOS
HYST
RX
T
ASSERT
±
450
±
600
±
770
ppm
RX_LOS Output Hys-
teresis
(4)
3
dB
RX_LOS &
RX_LOSYNC Output
Assert Time
(4, 5)
100
μ
s
RX_LOS &
RX_LOSYNC Output
Deassert Time
(4, 5)
RX
T
DEASSERT
100
RX_MON Transfer
Slope
(6)
RX_MON Dark Offset
Voltage
(6)
RX_MON Output
Voltage at
P
IN
=
–
17 dBm
(6)
RX_MON Output
Voltage at
P
IN
=
–
7 dBm
(6)
4.4
mV/
μW
mV
53
142
900