7

Table 2. Pin description

Pin

Name

Function/Description

Engagement

Order(insertion)

Notes

1

VeeT

Transmitter Ground

1

2

TX Fault

Transmitter Fault Indication

3

1

3

TX Disable

Transmitter Disable - Module disables on high or open

3

2

4

MOD-DEF2

Module Definition 2 - Two wire serial ID interface

3

3

5

MOD-DEF1

Module Definition 1 - Two wire serial ID interface

3

3

6

MOD-DEF0

Module Definition 0 - Grounded in module

3

3

7

Rate Selection

Not Connected

3

8

LOS

Loss of Signal

3

4

9

VeeR

Receiver Ground

1

10

VeeR

Receiver Ground

1

11

VeeR

Receiver Ground

1

12

RD-

Inverse Received Data Out

3

5

13

RD+

Received Data Out

3

5

14

VeeR

Reciver Ground

1

15

VccR

Receiver Power -3.3 V ±5%

2

6

16

VccT

Transmitter Power -3.3 V ±5%

2

6

17

VeeT

Transmitter Ground

1

18

TD+

Transmitter Data In

3

7

19

TD-

Inverse Transmitter Data In

3

7

20

VeeT

Transmitter Ground

1

Notes:

1. TX Fault is an open collector/drain output which should be pulled up externally with a 4.7K

 – 10 K resistor on the host board to a supply

<VccT+0.3 V or VccR+0.3 V. When high, this output indicates a laser fault of some kind. Low indicates normal operation. In the low state, the

output will be pulled to < 0.8 V.

2. TX disable input is used to shut down the laser output per the state table below. It is pulled up within the module with a 4.7-10 K

 resistor.

Low (0 – 0.8 V): Transmitter on

Between (0.8 V and 2.0 V): Undefined

High (2.0 – 3.465 V): Transmitter Disabled

Open: Transmitter Disabled

3. Mod-Def 0,1,2. These are the module definition pins. They should be pulled up with a 4.7-10 K

 resistor on the host board to a supply less

than VccT +0.3 V or VccR+0.3 V.

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

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

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

4. LOS (Loss of Signal) is an open collector/drain output which should be pulled up externally with a 4.7 K

 – 10 K resistor on the host board to

a supply < VccT,R+0.3 V. When high, this output indicates the received optical power is below the worst case receiver sensitivity (as defined by

the standard in use). Low indicates normal operation. In the low state, the output will be pulled to < 0.8 V.

5. RD-/+: These are the differential receiver outputs. They are AC coupled 100

 differential lines which should be terminated with 100  differ-

ential at the user SERDES. The AC coupling is done inside the module and is thus not required on the host board. The voltage swing on these

lines must be between 370 and 2000 mV differential (185 – 1000 mV single ended) according to the MSA. Typically it will be 1500mv differen-

tial.

6. VccR and VccT are the receiver and transmitter power supplies. They are defined as 3.135 – 3.465 V at the SFP connector pin. The in-rush

current will typically be no more than 30 mA above steady state supply current after 500 nanoseconds.

7. TD-/+: These are the differential transmitter inputs. They are AC coupled differential lines with 100

 differential termination inside the

module. The AC coupling is done inside the module and is thus not required on the host board. The inputs will accept differential swings of

500 – 2400 mV (250 – 1200 mV single ended). However, the applicable recommended differential voltage swing is found in Table 5.