Oplink Communications, Inc

4

S0219. Rev04. (web) 2012.06.18

TRD148xL2/E2/X2-G

Laser Safety: All transceivers are Class I Laser products per

FDA/CDRH and IEC-60825 standards. They must be operated

under specified operating conditions.

Oplink Communications, Inc.

This product complies with

21 CFR 1040.10 and 1040.11

Meets Class I Laser Safety Requirements

Application Notes

Host Board Termination & Coupling

Electrical interface: All signal interfaces are compliant with the

SFP MSA specification. The high speed DATA interface is differential

AC-coupled internally with 0.1μF and can be directly connected to

a 3.3V SERDES IC. All low speed control and sense output signals

are open collector TTL compatible and should be pulled up with a

4.7 - 10kΩ resistor on the host board

Loss of Signal (LOS): The Loss of Signal circuit monitors the level

of the incoming optical signal and generates a logic HIGH when an

insufficient photocurrent is produced.

TX Start-up: During power up or hot plugging the DWDM SFP

module will initially set theTX to the correct operating temperature.

Depending on the ambient temperature this may take several

seconds to 1 minute. When the Tx has reached the required

temperature the Tx is switched on and active. At this point the Tx is

guaranteed to be within +/-0.2nm of the appropriate ITU wavelength

and will settle to +/-0.05nm within the time limit set by the MSA.

TX_Fault: The output indicates LOW when the transmitter is

operating normally, and HIGH with a laser fault including laser

end-of-life. TX Fault is an open collector/drain output that should

be pulled up with a 4.7 - 10kΩ resistor on the host board. TX Fault

is latched per SFP MSA.

TX_Disable: When the TX Disable pin is at logic HIGH, the

transmitter optical output is disabled (less than -45dBm).

Serial Identification and Monitoring: The module definition of

SFP is indicated by the three module definition pins, MOD_DEF(0),

MOD_DEF(1) and MOD_DEF(2). Upon power up, MOD_DEF(1:2)

appear as NC (noconnection), and MOD_DEF(0) is TTL LOW. When

the host system detects this condition, it activates the serial protocol

clock signal (SCL). The positive edge clocks data into the EEPROM

segments of the SFP that are not write protected, and the negative

edge clocks data from the SFP.

The serial data signal (SDA) is for serial data transfer. The host

uses SDA in conjunction with SCL to mark the startand end of

serial protocol activation. The supported monitoring functions

are internal temperature, supply voltage, bias current, transmitter

power, average receiver signal, all alarms and warnings and software

monitoring of TX Fault/LOS. The device is internally calibrated.

The data transfer protocol and the details of the mandatory and

vendor specific data structures are defined in the MSA.

Power supply and grounding: The power supply line shouldbe

well-filtered. All 0.1μF power supply bypass capacitors should be

as close to the transceiver module as possible.

R: 4.7 to 10kΩ

CAP Values in μF

TX DATA IN+

1H coil or ferrite bead

µ

(<0.2 Ω series resistance)

0.1

TX DATA IN-

TX Disable

0.1

0.1

to 50 Ωload

3.3V

RX DATA OUT+

RX DATA OUT-

MOD_DEF(0)

MOD_DEF(1)

MOD_DEF(2)

LOS

to 50Ω load

TX Fault

Vcc

3.3V

Vcc

50Ω line

50Ω line

50Ω line

50Ω line

100

R

R

R

R

R

8

5

4

6

2

18

19

3

15

16

13

12

1, 9,10,11,14,17,20

SFP