Document Outline
- List of Figures
- 1. Laser Bias Monitor Circuitry.
- 2. Back Facet Monitor Circuitry.
- Features
- Applications
- Description
- Connection Diagram
- Pin Descriptions
- XMT5170-155 Block Diagram
- Functional Description
- Performance Specifications Absolute Maximum Ratings
- Characteristics
- Drawing Dimensions
- XMT5170X 155 - XX
- Handling Precautions
424
155 Mb/s Logic Interface Laser
Transmitter for OC3/STM1
Preliminary Technical Data
XMT5170-155
Preliminary Product Disclaimer
This preliminary data sheet is provided to assist you in the evaluation of engineering samples of the product which is under development
and targeted for release during 1997. Until Hewlett-Packard releases this product for general sales, HP reserves the right to alter prices,
specifications, features, capabilities, function, manufacturing release dates, and even general availability of the product at any time.
Features
SONET/SDH Compliant to
STM1 L-1.1
OC3 LR-1
40
C to +85
C Operation
Compact 20 Pin Package
ECL/PECL Logic Interface
Multisourced Pinout
Fully Interchangeable High
and Low Power Versions
Applications
SONET/SDH Systems
Single Mode ATM
Fiber to the Home
Data Communications
Networks
Description
The XMT5170-155 is a high
performance uncooled optical
laser transmitter for CCITT SDH
and ANSI SONET applications. It
is designed with an ECL/PECL
logic interface for 155 MBd
transmission.
The transmitter incorporates
several features which simplify
system design. It may be
operated with either +5 V or 5 V
power supplies. Standard 10 KH
ECL data interface enables direct
interface with PECL or ECL logic.
The compact transmitter module
contains a pigtailed laser, data
interface, bias and modulation
control circuitry. Thus, no
external components or adjust-
ments are necessary. Finally, a
laser disable input is provided to
shut down the laser for standby
or test purposes.
The XMT5170-155 has -2 dBm
mean output power for long haul
systems.
The XMT5170-155 includes
analog outputs which are
proportional to laser current and
optical power. These may be used
with external circuitry to detect
end-of-life, or over temperature
conditions.
The transmitter is packaged in a
20 pin 0.4" pitch DIP. An
evaluation board is available for
this product. Contact your local
representative for more details.
(5/97)
425
VCC
MONITOR
PHOTODIODE
200
3 k
PIN 19
PIN 17
3 k
TO LASER BIAS
CONTROL CIRCUITRY
VCC
LASER
10
3 k
PIN 2
PIN 4
3 k
VEE
MODULATION
CURRENT
IBIAS
1
2
3
4
5
6
7
8
9
10
20
19
18
17
16
15
14
13
12
11
NC
LASER BIAS MONITOR (+)
NC
LASER BIAS MONITOR ()
VEE
VCC
TRANSMIT DISABLE
VCC
VCC
NC
NC
LASER BACK FACET MONITOR (+)
VCC
LASER BACK FACET MONITOR ()
DATA
DATA
VEE
CASE GROUND (SEE NOTE BELOW)
VCC
CASE GROUND (SEE NOTE BELOW)
FIBER PIGTAIL
Pins 15, 16, DATA, DATA:
These are differential ECL inputs.
If open circuited they float to V
BB
(V
CC
1.3 V).
Pin 17, Laser Back Facet
Monitor ():
See Figure 2.
Pin 19, Laser Back Facet
Monitor (+):
See Figure 2.
Connection Diagram
Top View
Pin Descriptions
Pins 1, 3, 10, 20, NC:
These pins should not be con-
nected and should be left open
circuit on the application PCB.
Pin 2, Laser Bias Monitor (+):
See Figure 1.
Pin 4, Laser Bias Monitor ():
See Figure 1.
Pins 5,14, V
EE
:
These pins are connected to
ground in +5 V systems and 5 V
in negative supply systems.
Pins 6, 8, 9, 12, 18, V
CC
:
These pins are connected to +5 V
for positive supply systems and
ground for 5.2 V systems.
Pin 7, Transmit Disable:
Pin 7 floats to V
EE
when open
circuited, enabling the
transmitter. It must be biased
within 3 V of V
CC
to disable.
Pins 11,13, Ground:
The XMT5170-155 case is plastic,
therefore pins are not connected.
Figure 1. Laser Bias Monitor Circuitry.
Figure 2. Back Facet Monitor Circuitry.
426
XMT5170-155 Block Diagram
Functional Description
The ECL input allows operation
from many logic families and
both single-ended or differential
signals. For single-ended
operation both DATA and DATA
are internally tied to a V
BB
. The
unused input then requires no
connection or biasing.
The disable function disables the
laser bias and modulator. The
switching threshold is V
CC
3.2 V.
If this input is not connected the
module is enabled. This input
may be connected to a CMOS HI
or tied to V
CC
to disable.
The module provides the
necessary bias and modulation
control to maintain the extinction
ratio at better than 10 dB and the
waveform is compliant with
SONET/SDH Eyemask standard
G.957.
The laser bias control loop
compensates for temperature
induced variations in laser
performance. The bias current
monitor indicates the amount of
dc current supplied to the laser.
(This is approximately the laser
threshold current).
The rear facet monitor is a signal
proportional to the laser output
power. This can be used as part
of a HI/LO light alarm.
In the absence of data the laser
will emit a mean optical power
within the specified limits. The
extinction ratio and duty cycle
distortion are specified assuring a
50% duty cycle at the correct
data rate.
ECL
INPUT
LASER
MODULATOR
LASER
BIAS
DRIVER
LASER
BIAS
CONTROL
DATA
DATA
LASER
PHOTODIODE
(REAR FACET
MONITOR)
DISABLE
LASER BIAS
MONITOR
REAR FACET
MONITOR
427
Performance Specifications
Absolute Maximum Ratings
Absolute maximum limits mean that no catastrophic damage will occur if the product is subjected to these ratings for short periods, provided
each limiting parameter is in isolation and all other parameters have values within the performance specification. It should not be assumed that
limiting values of more than one parameter can be applied to the product at the same time.
Parameter
Minimum
Nominal
Maximum
Units
Notes
Supply Voltage
-
-
7
V
-
Operating Case Temperature
XMT5170A-155
40
-
+85
C
-
XMT5170B-155
0
-
+70
C
-
Storage Temperature
-40
-
+85
C
-
Fiber Tensile Strength
10
-
-
N/10s
1
Fiber Bend Radius
32
-
-
mm
-
Lead Soldering (Temperature/Time)
-
-
+260/10
C/Sec
-
Characteristics
Parameter
Minimum
Nominal
Maximum
Units
Notes
Center Wavelength
1280
-
1335
nm
2
Spectral Width (RMS)
-
-
4
nm
2
Average Output Power
5
2.5
0
dBm
3
Rise Time (10% - 90%)
-
-
2
ns
-
Fall Time (10% - 90%)
-
-
2
ns
-
Extinction Ratio
10
-
-
dB
-
Bias Monitor
-
0.1
-
mA/mV
4
Rear Facet Monitor Output
5
-
50
mV
5
Supply Voltage
4.75
5.0
5.5
V
6
Supply Current
-
70
130
mA
7
Tx Disable
V
CC
3.2
-
V
CC
V
-
Output Waveform
SONET/SDH Eyemask Compliant G.957
Notes:
1. In a coaxial direction with fiber feed through.
2. Over operating temperature range. A narrower operating temperature range will result in a smaller center wavelength spread.
Contact Hewlett-Packard for details.
3. Other output power options are available. Contact Hewlett-Packard for details.
4. Common mode signal V
EE
+ 3.5 V nominal.
5. Common mode signal V
EE
+ 1.2 V nominal.
6. With V
EE
connected to -5 V, V
CC
must be at 0 V. With V
CC
at +5 V, V
EE
must be at 0 V.
7. End of life at Tmax.
428
L
E
C
D
F
G
B
A
1
10
20
11
ALL DIMENSIONS IN MILLIMETERS
MIN.
NOM.
32.9
16.0
2.6
2.7
400
2.54
0.46
10.16
A
B
C
D
E
F
G
H
J
K
L
DIM.
MAX.
33.2
17.5
16.3
9.27
2.95
3.2
4.64
1220
K
H
J
Drawing Dimensions
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