2.488Gbps SFP Optical Transceiver, 20km Reach

ST-OC48-20BS

2.488Gbps SFP Bi-Directional Transceiver, 20km Reach

TX1550nm / RX1310nm

Features

*Dual data-rate of 2.488Gbps/2.125Gbps operation

*1550nm DFB laser and PIN photodetector for 20km transmission

*Compliant with SFP MSA and SFF-8472 with simplex LC receptacle

*Digital Diagnostic Monitoring:

  Internal Calibration or External Calibration

*Compatible with SONET OC-48 system

*Compatible with RoHS

*+3.3V single power supply

*Operating case temperature:

  Standard :  0 to +70°C

Applications

*SDH STM-16 and SONET OC-48 system

*Fiber Channel

*Switch to Switch interface

*Switched backplane applications

*Router/Server interface

*Other optical transmission systems

Description

   The BIDI SFP transceivers are high performance, cost effective modules supporting dual data-rate of 2.488Gbps/2.125Gbps and 20km transmission distance with SMF.

The transceiver consists of three sections: a DFB laser transmitter, a PIN photodiode integrated with a trans-impedance preamplifier (TIA) and MCU control unit. All modules satisfy class I laser safety requirements.

The transceivers are compatible with SFP Multi-Source Agreement (MSA) and SFF-8472. For further information, please refer to SFP MSA.

Absolute Maximum Ratings

Table 1 - Absolute Maximum Ratings

Recommended Operating Conditions           

Table 2 - Recommended Operating Conditions

Optical and Electrical Characteristics

ST-OC48-20BS+ :  (DFB and PIN, 1550nm, 20km Reach)

Table 3 - Optical and Electrical Characteristics

Notes:

1. The optical power is launched into SMF.
2. PECL input, internally AC-coupled and terminated.
3. Measured with a PRBS 2²³-1 test pattern @2488Mbps, BER ≤1×10^-12.
4. Internally AC-coupled.

Timing and Electrical

Table 4 - Timing and Electrical

Diagnostics

Table 5 – Diagnostics Specification

Digital Diagnostic Memory Map

The transceivers provide serial ID memory contents and diagnostic information about the present operating conditions by the 2-wire serial interface (SCL, SDA).

The diagnostic information with internal calibration or external calibration all are implemented, including received power monitoring, transmitted power monitoring, bias current monitoring, supply voltage monitoring and temperature monitoring.

The digital diagnostic memory map specific data field defines as following.

Pin Definitions

Pin Diagram

Pin Descriptions

Notes:

Plug Seq.: Pin engagement sequence during hot plugging.

1) TX Fault is an open collector output, which should be pulled up with a 4.7k~10kΩ resistor on the host board to a voltage between 2.0V and Vcc+0.3V. Logic 0 indicates normal operation; Logic 1 indicates a laser fault of some kind. In the low state, the output will be pulled to less than 0.8V.

2) TX Disable is an input that is used to shut down the transmitter optical output. It is pulled up within the module with a 4.7k~10kΩ resistor. Its states are:

Low (0 to 0.8V):             Transmitter on

(>0.8V, < 2.0V):             Undefined

High (2.0 to 3.465V):         Transmitter Disabled

Open:                      Transmitter Disabled

3) Mod-Def 0,1,2. These are the module definition pins. They should be pulled up with a 4.7k~10kΩ resistor on the host board. The pull-up voltage shall be VccT or VccR.

Mod-Def 0 is grounded by the module to indicate that the module is present

Mod-Def 1 is the clock line of two wire serial interface for serial ID

Mod-Def 2 is the data line of two wire serial interface for serial ID

4) LOS is an open collector output, which should be pulled up with a 4.7k~10kΩ resistor. Pull up voltage between 2.0V and Vcc+0.3V. Logic 1 indicates loss of signal; Logic 0 indicates normal operation. In the low state, the output will be pulled to less than 0.8V.

5) RD-/+: These are the differential receiver outputs. They are internally AC-coupled 100 differential lines which should be terminated with 100Ω (differential) at the user SERDES.

6) TD-/+: These are the differential transmitter inputs. They are internally AC-coupled, differential lines with 100Ω differential termination inside the module.

Ordering information