SRC12 - Oplink Communications, Inc

OC-12/STM-4 Receiver with
Clock Recovery
SRC12 Series
Product Description
The SRC12 is a Receiver Module with internal clock recovery designed to
meet or exceed the SONET/SDH optical interface requirements at OC-12/
STM-4 (622 Mb/s) data rate. Highly reliable InGaAs/InP PIN photodiodes
are used to cover the entire long wavelength range from 1100 nm to 1550
nm.
The receiver features a low noise GaAs transimpedance IC with AGC capability to provide an extremely wide dynamic range and high sensitivity.
A Phase Lock Loop (PLL) circuit is included to perform the clock recovery
function and resampling of the data.
The SRC12 receiver requires a single +5 V supply. The DATA & CLOCKinterface signals are differential PECL while the SIGNAL DETECT outputs have
TTL interface.
The SRC12 module can operate over an operating temperature range of
0°C to +70°C (“H” option) or -40°C to +85°C (“I” option). It is housed in a
20-pin dual-in-line metal package with integral ST, FC or SC connector
receptacle or fiber pigtail (50 µm multimode fiber). The fiber pigtail is terminated with ST, FC or SC connector.
Features
 Full compliance with SONET/SDH OC-12/
STM-4 specifications
 Long Reach and Intermediate Reach
 Phase-Lock-Loop (PLL) Clock Recovery
Related OC-12/STM-4 transmitters & receivers
STX-12: 20-pin laser transmitter
SRX-12: 20-pin receiver without clock recovery (PECL SIGNAL DETECT)
SRX-12-L: 20-pin receiver without clock recovery (TTL SIGNAL DETECT)
SRC-12-S: 24-pin receiver with clock recovery
 - 40°C to +85°C Operating Temperature (“I”
option)
 Multi-sourced 20-pin DIP metal package
 FC, ST, SC-connectorized fiber pigtails or
Integral FC, SC or ST connector receptacle
 PECL DATA & CLOCK interface
 TTL SIGNAL DETECT interface
Absolute Maximum Ratings
Parameter
Storage Temperature
Operating Temperature
Operating & Storage Humidity
Supply Voltage
Lead Soldering Temperature & Time
“I” option
“H” option
Symbol
Minimum
Maximum
Units
TST
- 40
+ 85
°C
- 40
+ 85
0
+ 70
-
-
85
%
VCC
0
+ 6.0
V
-
-
TOP
°C
260°C, 10 sec
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Oplink Communications,
Inc.
SRC12 Series
Receiver Electrical Interface (Over Operating Case Temperature)
Parameter
Symbol
Minimum
Typical
Maximum
Units
VCC
4.75
5.0
5.25
V
ICC
-
160
210
mA
VOH
VCC - 1.11
-
VCC - 0.67
V
VOL
VCC - 2.00
-
VCC - 1.50
V
Output HIGH Voltage (SIGNAL DETECT)
VOH
2.7
-
VCC
V
Output LOW Voltage (SIGNAL DETECT)
VOL
0
-
0.5
V
Supply Voltage
Supply Current
Output HIGH Voltage (DATA & CLOCK)
Output LOW Voltage (DATA & CLOCK)
1
1
1
With termination of 50 ohm to VCC - 2V.
Receiver Performance Characteristics (Over Operating Case Temperature)
Parameter
Symbol
Minimum
Typical
Maximum
Units
B
622.08 - 200ppm
622.08
622.08 + 200ppm
Mb/s
Pmin
- 28.0
- 30.0
-
dBm
Data Rate
Receiver Sensitivity (10 BER)
-10
1
Pmax
- 7.0
0
-
dBm
Increasing Light Input
Psd+
-
-
- 28.0
dBm
Decreasing Light Input
Psd-
- 40.0
-
-
dBm
-
0.5
-
dB
Maximum Input Optical Power (10 BER)
-10
Signal Detect Thresholds
1
Signal Detect Hysteresis
λ
1100
-
1600
nm
CLKJ
-
-
0.01
UIrms
Wavelength of Operation
Output Clock Jitter
Jitter Tolerance & Transfer Function
1
compliant with ITU Recommendation G.958
Specified in Average Optical Input Power with single mode fiber and measured at 1300 nm wavelength with 223-1 PRBS.
Interface Circuit
1 µH coil or
ferrite inductor
10
+
0.01
11
SIGNAL
DETECT+
82
12
(TTL LEVELS)
SIGNAL
DETECT -
+5 volt
SRC-12
14
82
82
0.1
82
DATA+
7
DATA -
9
(PECL LEVELS)
CLOCK+
4
CLOCK -
5
1, 13, 20
10
6, 8, 15
130
130
130
(PECL LEVELS)
130
RESISTOR VALUES ARE IN OHM, CAPACITOR VALUES ARE IN µF UNLESS OTHERWISE INDICATED
Oplink Communications, Inc.
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SRC12 Series
Application Notes
Receiver Circuit: The receiver converts the incident optical power to a
photocurrent via a high performance PIN photodiode. The photocurrent
is converted to a voltage signal by a transimpedance amplifier. This
signal is then amplified by additional gain stages and processed through
a shaping filter and a comparator to generate the data to the clock
recovery circuit. The clock recovery circuit uses a Phase Lock Loop (PLL) to
recover the clock from the data and resamples the data to generate clean
and reshaped differential DATAoutputs. Also provided are differential
recovered CLOCK outputs.
Both differential DATA+ and DATA- as well as CLOCK+ and CLOCK- outputs
are open emitter PECL levels requiring termination (50 ohms to VCC - 2
volts or 510 ohms to GND is recommended). For optimum performance,
both outputs should be terminated in the same manner, even if only
one is used.
The Signal Detect circuit monitors the level of the incoming optical signal
and generates a logic LOW (TTL) signal when insufficient photocurrent
is produced. When this happens, the CLOCK+ and CLOCK- outputs are
locked to an internal reference frequency of 622.08 ± 0.2 MHz, the DATA+
output is held at logic HIGH and the DATA- output is held at logic LOW.
Interface Circuit: The power supply line should be wellfiltered. The
power supply should be bypassed by 0.01 or 0.1 µF ceramic chip
capacitors placed as close to the receiver module as possible. If the
receiver outputs drive long traces or multiple loads, the use of an ECL
buffer gate to isolate the receiver from transmission line reflections is
recommended.
Pin Assignments (Top View)
DATA & CLOCK Timing Diagram
CASE
1
20
CASE
N/C
2
19
N/C
N/C
3
18
N/C
CLOCK +
4
17
N/C
CLOCK -
5
16
N/C
GND
6
15
GND
DATA+
7
14
SIGNAL DETECT -
GND
8
13
CASE
DATA -
9
12
SIGNAL DETECT+
10
11
VCC (+5 V)
N/C
Set-up
450 ps typical
Hold
450 ps typical
DATA
CLOCK
N/C: No internal connection
All CASE pins should be grounded
Pigtail Package
The pigtail length from the package edge is
1.0 meter minimum, 1.1 meter typical.
Dimension in inches
Oplink Communications, Inc.
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SRC12 Series
SC-receptacled Package
Dimension in inches
46335 Landing Parkway Fremont, CA 94538-6407 Tel: (510) 933-7200 Fax: (510) 933-7300 Email: [email protected]
FC-receptacled Package
Dimension in inches
ST Receptacle Package
Dimension in inches
Ordering Information
SRC
8
Supply Voltage
RX only 5V= 8
1
2
Receivers
X
R
1
Wavelength Range
1100~1600nm PIN
0
0
0
Temperature Range
Connector Type & Option
-40 ~85˚C= I
0~70˚C= H
Pigtail FC= P1
Pigtail ST= P2
Pigtail SC= P3
ST Connector= C1
FC Connector= C2
SC Connector= C3
Oplink Communications, Inc. reserves the right to make changes in equipment design or specifications without notice. Information supplied by Oplink Communications, Inc. is believed to be accurate and reliable. However, no responsibility is assumed by Oplink Communications, Inc. for its use nor for any infringements
of third parties, which may result from its use. No license is granted by implication or otherwise under any patent right of Oplink Communications, Inc.
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© 2008, Oplink Communications, Inc.
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