dtr-2488-sm-lc-w-g-cwdm OPLINK Communications Inc., dtr-2488-sm-lc-w-g-cwdm Datasheet - Page 4

• Manufacturer Part Number: dtr-2488-sm-lc-w-g-cwdm
• Description: Oc-48/stm-16 2x5 Sff Single Mode Cwdm Transceivers
• Manufacturer: OPLINK Communications Inc.

Application Notes
DATA interface (DC-coupled modules): The interface
circuit for standard DC-coupled modules with direct-coupled
LV-PECL interface is shown in Fig. 1. The transmitter input
has internal 50Ω termination.
DATA interface (AC-coupled modules): For modules with
AC coupling option, both transmitter and receiver interfaces
have internal bias, 50Ω termination and AC coupling capacitors.
The transmitter can be connected directly to the driving
SERDES as shown in Fig. 2. The receiver can be connected
directly to the external 50Ω loads (termination resistor of the
SERDES). For best performance, both DATA+ & DATA-
should be used.
+
+
SIGNAL DETECT
10
SIGNAL DETECT
ferrite inductor
10
ferrite inductor
+3.3V
+3.3V
Vcc
Vcc
1 H coil or
1 H coil or
µ
µ
ferrite inductor
TX DISABLE
ferrite inductor
TX DISABLE
0.1
1 H coil or
0.1
1 H coil or
µ
µ
DTR-2488-SM-LC/LS-W-G-CWDM
0.1
0.1
+
+
10
10
3
8
6
3
8
6
DTR-2488-SM
Capacitor values in F, Resistor values in
Capacitor values in F, Resistor values in
DTR-2488-SM
1
0.1
1
0.1
Fig.1 DC-coupled modules
Fig.2 AC-coupled modules
POSTS
POSTS
GND
2
2
GND
100
7
100
7
depending on SERDES
10
9
5
10
4
5
4
9
4
TD+
RD+
TD-
RD-
µ
TXD+
TXD+
TXD -
TXD-
RXD+
RXD+
RXD -
RXD-
µ
SIGNAL DETECT: The SIGNAL DETECT circuit monitors
the incoming optical signal level and generates a logic LOW
signal when an insufficient photocurrent is produced. The output
is LV-TTL with no termination required.
TX DISABLE: The transmitter is normally enabled (i.e. when
the TX DISABLE control input is not connected). When the
TX DISABLE control input voltage is higher than V
the laser is turned off independent of the input data.
Power supply and grounding: The power supply line should
be well-filtered. All 0.1µF power supply bypass capacitors
should be as close to the DTR transceiver module as possible.
The module case ground is internally AC-coupled to the circuit
ground.
160
50
50
50
50
50
Ω
50
Ω
Ω
depending on SERDES
Ω
160
Ω
Ω
line
line
line
50
50
line
line
line
Ω
Ω
line
line
160
160
Ω
100
Ω
100
160
160
SERDES
LV-PECL
LV-PECL
21737-0291, Rev. B
07-21-2005
CC
- 1.3V,