1250M BI-DI SC SFP Transceiver With DDM

1. ATM
2. SONT/SDH/PDH
3. FDDI
4. Fiber Channel
5. CWDM

Function description：
The SFP (Small Form Factor Pluggable ) transceivers is compliant with SFP MSA (Multi-Source Agreement ) and SFF-8472. All modules satisfy Class I Laser Safety requirements in accordance with the international IEC-825 standards.
The transmit and receive functions are contained in a SFP 20 pin package with a Duplex LC connector interface. The transmitter incorporates a highly reliable 1310 nm or 1550 nm Laser (FP laser for narrow、Intermediate distance and DFB laser for long distance) and a driver circuit which converts data to light with APC function. The output power can be disable via the single TX_Disable pin. Logic HIGH level disables the transmitter. The receiver incorporates an efficient InGaAs/InP PIN or APD photodiode receiver converting the light signal into an electrical current which is amplified and regenerated into data. The transimpedance amplifier IC has internal AGC for wide dynamic range. The postamplifier is AC coupled to preamplifier through a capacitor and a low pass filter. It can be enough to pass the signal from 100Mb/s to 1.25Gb/s without significant sensitivity. A Signal Detect status output flag is also provided.
The transceiver operates from a single +3.3V power supply over an operating temperature range of 0 to +70°C or –40 to+85°C. The transceiver uses the SFP 20-pin connector to allow hot plug capability. Detailed product information in EEPROM and digital diagnostic monitoring is offered

Recommended Circuit：

EEPROM Description:

The TT-serial SFP module contains an EEPROM. It provides access to sophisticated identification information that describes the transceiver’s capabilities, standard interfaces, manufacturer. The serial interface uses the 2-wire serial CMOS EEPROM protocol defined for the ATMEL AT24C01A/02/04 family of components. When the serial protocol is activated, the host generates the serial clock signal (SCL MOD_DEF1). The positive edge clocks data into those segments of the EEPROM that are not write-protected within the SFP transceiver. The negative edge clocks data from the SFP transceiver. The serial data signal (SDA MOD_DEF2) is bi-directional for serial protocol activation. The memories are organized as a series of 8-bit data words that can be addressed individually or sequentially.
The module provide diagnostic information about the present operating conditions. The transceiver generates this diagnostic data by digitization of internal analog signals. Calibration and alarm/warning threshold power monitoring, bias current monitoring, supply voltage monitoring and temperature monitoring all are implemented. The diagnostic data are raw A/D values and must be converted to real world units using calibration constants stored in EEPROM locations 56-95 at wire serial bus address A2h. The digital diagnostic memory map specific data field define according to following.