HFCT-5961TG Avago Technologies US Inc., HFCT-5961TG Datasheet - Page 8

• Manufacturer Part Number: HFCT-5961TG
• Manufacturer: Avago Technologies US Inc.

Specifications of HFCT-5961TG

• Optical Fiber Type: TX/RX
• Data Transfer Rate: 155Mbps
• Optical Rise Time: 2ns
• Optical Fall Time: 2ns
• Operating Temperature Classification: Commercial
• Peak Wavelength: 1360nm
• Package Type: DIP With Connector
• Operating Supply Voltage (min): 3.1V
• Operating Supply Voltage (typ): 3.3V
• Operating Supply Voltage (max): 3.5V
• Output Current: 50mA
• Operating Temp Range: 0C to 70C
• Mounting: Snap Fit To Panel
• Pin Count: 10
• Lead Free Status / RoHS Status: Compliant

Figure 6b. Recommended ac Coupled Interface Circuit
The HFCT-5961TL/TG/NL/NG/ATL/ATG have a transmit
disable function which is a single-ended +3.3 V TTL input
which is dc-coupled to pin 8.
As for the receiver section, it is internally ac-coupled be-
tween the preamplifier and the postamplifier stages. The
actual Data and Data-bar outputs of the postamplifier are
dc-coupled to their respective output pins (pins 4, 5). The
two data outputs of the receiver should be terminated
with identical load circuits.
Signal Detect is a single-ended, +3.3 V PECL compatible
output signal that is dc-coupled to pin 3 of the module.
Signal Detect should not be ac-coupled externally to the
follow-on circuits because of its infrequent state changes.
Power Supply Filtering and Ground Planes
It is important to exercise care in circuit board layout to
achieve optimum performance from these transceivers.
Figures 6a and 6b show the power supply circuit which
complies with the small form factor multisource agree-
ment. It is further recommended that a continuous ground
plane be provided in the circuit board directly under the
transceiver to provide a low inductance ground for signal
return current. This recommendation is in keeping with
good high frequency board layout practices.
8
T
Note: C1 = C2 = C3 = 10 nF or 100 nF
Note A: CIRCUIT ASSUMES OPEN EMITTER OUTPUT
Note B: WHEN INTERNAL BIAS IS PROVIDED REPLACE SPLIT RESISTORS WITH 100 Ω TERMINATION
* C4 AND C5 ARE OPTIONAL BYPASS CAPACITORS FOR ADDITIONAL LOW FREQUENCY NOISE FILTERING.
DIS
T
R
X
X
(LVTTL)
10
1
9
2
8
3
7
82 Ω
130 Ω
4
130 Ω
V
6
CC
5
(+3.3 V)
82 Ω
130 Ω
130 Ω
C2
C1
100 nF
1 µH
1 µH
100 nF
100 nF
100 nF
100 nF
C5 *
10 µF
C4 *
10 µF
Package footprint and front panel considerations
The Avago Technologies transceivers comply with the cir-
cuit board “Common Transceiver Footprint” hole pattern
defined in the current multisource agreement which de-
fined the 2 x 5 package style. This drawing is reproduced
in Figure 7 with the addition of ANSI Y14.5M compliant
dimensioning to be used as a guide in the mechanical
layout of your circuit board. Figure 8 shows the front panel
dimensions associated with such a layout.
Eye Safety Circuit
For an optical transmitter device to be eye-safe in the
event of a single fault failure, the transmitter must either
maintain eye-safe operation or be disabled.
The HFCT-5961TL/TG/NL/NG/ATL/ATG is intrinsically eye
safe and does not require shut down circuitry.
Z = 50 Ω
Z = 50 Ω
Z = 50 Ω
Z = 50 Ω
Z = 50 Ω
V
CC
C3
(+3.3 V)
100 nF
100 nF
10 µF
130 Ω
82 Ω
130 Ω
V
130 Ω
CC
82 Ω
(+3.3 V)
V
CC
82 Ω
130 Ω
(+3.3 V)
RD+
TD-
TD+
RD-
SD
130
Ω
LVPECL
V
CC
V
(+3.3 V)
CC
(+3.3 V)
NOTE A
NOTE B