125 Megabaud Versatile Link
The Versatile Fiber Optic
Connection
Technical Data
Features
• Data Transmission at Signal
Rates of 1 to 125 MBd over
Distances of 100 Meters
• Compatible with Inexpen-
sive, Easily Terminated
Plastic Optical Fiber, and
with Large Core Silica Fiber
• High Voltage Isolation
• Transmitter and Receiver
Application Circuit Sche-
matics and Recommended
Board Layouts Available
• Interlocking Feature for
Single Channel or Duplex
Links, in a Vertical or
Horizontal Mount
Configuration
Applications
• Intra-System Links: Board-
to-Board, Rack-to-Rack
• Telecommunications
Switching Systems
• Computer-to-Peripheral
Data Links, PC Bus
Extension
• Industrial Control
• Proprietary LANs
• Digitized Video
• Medical Instruments
• Reduction of Lightning and
Voltage Transient
Susceptibility
Description
The 125 MBd Versatile Link
(HFBR-0507 Series) is the most
cost-effective fiber-optic solution
for transmission of 125 MBd data
over 100 meters. The data link
consists of a 650 nm LED
transmitter, HFBR-15X7, and a
PIN/preamp receiver, HFBR-
25X6. These can be used with
low-cost plastic or silica fiber.
One mm diameter plastic fiber
provides the lowest cost solution
for distances under 25 meters.
The lower attenuation of silica
fiber allows data transmission
over longer distance, for a small
difference in cost. These compo-
nents can be used for high speed
data links without the problems
common with copper wire
solutions, at a competitive cost.
The HFBR-15X7 transmitter is a
high power 650 nm LED in a low
cost plastic housing designed to
efficiently couple power into 1
mm diameter plastic optical fiber
and 200 µm Hard Clad Silica
(HCS®) fiber. With the recom-
mended drive circuit, the LED
operates at speeds from 1-125
MBd. The HFBR-25X6 is a high
bandwidth analog receiver con-
taining a PIN photodiode and
internal transimpedance amplifier.
With the recommended applica-
tion circuit for 125 MBd
operation, the performance of the
complete data link is specified for
of 0-25 meters with plastic fiber
and 0-100 meters with 200 µm
HCS® fiber. A wide variety of
other digitizing circuits can be
combined with the HFBR-0507
Series to optimize performance
and cost at higher and lower data
rates.
HFBR-0507 Series
HFBR-15X7 Transmitters
HFBR-25X6 Receivers
HCS® is a registered trademark of Spectran Corporation.
2
HFBR-0507 Series
125 MBd Data Link
Data link operating conditions
and performance are specified for
the HFBR-15X7 transmitter and
HFBR-25X6 receiver in the
recommended applications
circuits shown in Figure 1. This
circuit has been optimized for 125
MBd operation. The Applications
Engineering Department in the
Agilent Optical Communication
Division is available to assist in
optimizing link performance for
higher or lower speed operation.
Recommended Operating Conditions for the Circuits in Figures 1 and 2.
Parameter Symbol Min. Max. Unit Reference
Ambient Temperature T
A070°C
Supply Voltage VCC +4.75 +5.25 V
Data Input Voltage – Low VIL VCC -1.89 VCC -1.62 V
Data Input Voltage – High V
IH VCC -1.06 VCC -0.70 V
Data Output Load RL45 55 ΩNote 1
Signaling Rate fS1 125 MBd
Duty Cycle D.C. 40 60 % Note 2
Link Performance: 1-125 MBd, BER ≤ 10-9, under recommended operating conditions with
recommended transmit and receive application circuits.
Parameter Symbol Min.[3] Typ.[4] Max. Unit Condition Reference
Optical Power Budget, 1 m POF OPBPOF 11 16 dB Note 5,6,7
Optical Power Margin, OPMPOF,20 3 6 dB Note 5,6,7
20 m Standard POF
Link Distance with l 20 27 m
Standard 1 mm POF
Optical Power Margin, OPMPOF,25 3 6 dB Note 5,6,7
25 m Low Loss POF
Link Distance with Extra l 25 32 m
Low Loss 1 mm POF
Optical Power Budget, 1 m HCS OPBHCS 7 12 dB Note 5,6,7
Optical Power Margin, OPMHCS,100 3 6 dB Note 5,6,7
100 m HCS
Link Distance with HCS Cable l 100 125 m
Notes:
1. If the output of U4C in Figure 1, page 4 is transmitted via coaxial cable, terminate with a 50 Ω resistor to VCC - 2 V.
2. Run length limited code with maximum run length of 10 µs.
3. Minimum link performance is projected based on the worst case specifications of the HFBR-15X7 transmitter, HFBR-25X6 receiver,
and POF cable, and the typical performance of other components (e.g. logic gates, transistors, resistors, capacitors, quantizer,
HCS cable).
4. Typical performance is at 25°C, 125 MBd, and is measured with typical values of all circuit components.
5. Standard cable is HFBR-RXXYYY plastic optical fiber , with a maximum attenuation of 0.24 dB/m at 650 nm and NA = 0.5.
Extra low loss cable is HFBR-EXXYYY plastic optical fiber, with a maximum attenuation of 0.19 dB/m at 650 nm and NA = 0.5.
HCS cable is HFBR-H/VXXYYY glass optical fiber, with a maximum attenuation of 10 dB/km at 650 nm and NA = 0.37.
6. Optical Power Budget is the difference between the transmitter output power and the receiver sensitivity, measured after
1 meter of fiber. The minimum OPB is based on the limits of optical component performance over temperature, process, and
recommended power supply variation.
7. The Optical Power Margin is the available OPB after including the effects of attenuation and modal dispersion for the minimum
link distance: OPM = OPB - (attenuation power loss + modal dispersion power penalty). The minimum OPM is the margin
available for longterm LED LOP degradation and additional fixed passive losses (such as in-line connectors) in addition to the
minimum specified distance.
3
Hard Clad Silica Fiber (200 µm HCS) Transmitter Application Circuit: Performance of
the HFBR-15X7 transmitter in the recommended application circuit (Figure 1) for HCS; 1-125 MBd, 25°C.
Parameter Symbol Typical Unit Condition Note
Average Optical Power 200 µm HCS Pavg -14.6 dBm 50% Duty Note 1, Fig 3
Cycle
Average Modulated Power 200 µm HCS Pmod -16.2 dBm Note 2, Fig 3
Optical Rise Time (10% to 90%) tr3.1 ns 5 MHz
Optical Fall Time (90% to 10%) tf3.4 ns 5 MHz
High Level LED Current (On) IF,H 60 mA Note 3
Low Level LED Current (Off) IF,L 6 mA Note 3
Optical Overshoot - 200 µm HCS 30 %
Transmitter Application Circuit ICC 130 mA Figure 1
Current Consumption - 200 µm HCS
Notes:
1. Average optical power is measured with an average power meter at 50% duty cycle, after 1 meter of fiber.
2. To allow the LED to switch at high speeds, the recommended drive circuit modulates LED light output between two non-zero power
levels. The modulated (useful) power is the difference between the high and low level of light output power (transmitted) or input
power (received), which can be measured with an average power meter as a function of duty cycle (see Figure 3). Average Modulated
Power is defined as one half the slope of the average power versus duty cycle:
[Pavg @ 80% duty cycle - Pavg @ 20% duty cycle]
Average Modulated Power = ––——————————————————————
(2) [0.80 - 0.20]
3. High and low level LED currents refer to the current through the HFBR-15X7 LED. The low level LED “off” current, sometimes
referred to as “hold-on” current, is prebias supplied to the LED during the off state to facilitate fast switching speeds.
Plastic Optical Fiber (1 mm POF) Transmitter Application Circuit:
Performance of the HFBR-15X7 transmitter in the recommended application circuit (Figure 1) for POF; 1-
125 MBd, 25°C.
Parameter Symbol Typical Unit Condition Note
Average Optical Power 1 mm POF Pavg -9.7 dBm 50% Duty Note 1, Fig 3
Cycle
Average Modulated Power 1 mm POF Pmod -11.3 dBm Note 2, Fig 3
Optical Rise Time (10% to 90%) tr2.1 ns 5 MHz
Optical Fall Time (90% to 10%) tf2.8 ns 5 MHz
High Level LED Current (On) IF,H 19 mA Note 3
Low Level LED Current (Off) IF,L 3 mA Note 3
Optical Overshoot - 1 mm POF 45 %
Transmitter Application Circuit ICC 110 mA Figure 1
Current Consumption - 1 mm POF
4
Plastic and Hard Clad Silica Optical Fiber Receiver Application Circuit:
Performance[4] of the HFBR-25X6 receiver in the recommended application circuit (Figure 1); 1-125 MBd,
25°C unless otherwise stated.
Parameter Symbol Typical Unit Condition Note
Data Output Voltage - Low VOL VCC -1.7 V RL = 50 ΩNote 5
Data Output Voltage - High VOH VCC -0.9 V RL = 50 ΩNote 5
Receiver Sensitivity to Average Pmin -27.5 dBm 50% eye opening Note 2
Modulated Optical Power 1 mm POF
Receiver Sensitivity to Average Pmin -28.5 dBm 50% eye opening Note 2
Modulated Optical Power 200 µm HCS
Receiver Overdrive Level of Average Pmax -7.5 dBm 50% eye opening Note 2
Modulated Optical Power 1 mm POF
Receiver Overdrive Level of Average Pmax -10.5 dBm 50% eye opening Note 2
Modulated Optical Power 200 µm HCS
Receiver Application Circuit Current ICC 85 mA RL = ∞Figure 1
Consumption
Notes:
4. Performance in response to a signal from the HFBR-15X7 transmitter driven with the recommended circuit at 1-125 MBd over 1 meter
of HFBR-R/EXXYYY plastic optical fiber or 1 meter of HFBR-H/VXXYYY hard clad silica optical fiber.
5. Terminated through a 50 Ω resistor to VCC - 2 V.
6. If there is no input optical power to the receiver, electrical noise can result in false triggering of the receiver. In typical applications,
data encoding and error detection prevent random triggering from being interpreted as valid data. Refer to Applications Note 1066 for
design guidelines.
5
C1
0.001 C2
0.1
R5
22
Q1
BFQ52
R6
91 R7
91
Q2
BFQ52
C20
10 C19
0.1
T
X
V
EE
9
8
7
6
5
4
3
2
1
J1
Q2 BASE
Q1 BASE
T
X
V
CC
R
X
V
CC
PIN 19 10H116
PIN 18 10H116
R
X
V
EE
NC
L1
CB70-1812
1
23
4
5
13
12
10
914
7
8
11
6
1
2
3
4
8
5
8
5
1
2
3
4
12
13
5
78
9
3
4
17
15
19
18
R24
1K
R22
1K R18
51 R16
51
C17
0.1
V
BB
V
CC
C10
0.1
R19
51 R17
51 R15
1K
R23
1K
V
BB
C18
0.1
R25
1K R20
12
R21
62
V
CC
V
BB
3 V
C14
10
TL431
U5
MC10H116FN
C15
0.1 C11
0.1
C16
0.1 C12
0.1
R14
1K
V
BB
3V
C9
.47
R12
4.7
C13
0.1
HFBR-25X6
R13
4.7
U4C U4A U4B U3
R11*
R10
15
C8*
74ACTQ00
U1B
74ACTQ00
U1D
74ACTQ00
U1C
R9*
R8*
HFBR-15X7
C7
0.001
C6
0.1
C5
10
C4
0.001
C3
0.1
Q3
2N3904
V
CC
74ACTQ00
U1A
POF
300
300
1K
43 pF
R8
R9
R11
C8
HCS
82
82
470
120 pF
TOLERANCE
1%
1%
1%
1%
THE VALUES OF R8, R9, R11, AND
C8 ARE DIFFERENT FOR POF AND
HCS DRIVE CIRCUITS.
ALL CAPACITOR VALUES
ARE IN MICRO FARADS,
WITH 10% TOLERANCE
(UNLESS OTHERWISE NOTED).
ALL RESISTANCES ARE IN
OHMS WITH 5% TOLERANCE
(UNLESS OTHERWISE NOTED).
U2
MC10H116FN MC10H116FN
2
20
+
+
+
10 14
Figure 1. Transmitter and Receiver Application Circuit with +5 V ECL Inputs and Outputs.
5
Figure 2. Recommended Power Supply Filter and +5 V ECL Signal Terminations for
the Transmitter and Receiver Application Circuit of Figure 1.
Figure 4. Typical Optical Power
Budget vs. Data Rate.
Figure 3. Average Modulated Power.
OPTICAL POWER BUDGET –dB
10
21
15
9
DATA RATE – MBd
9070 130 150
19
11
110
17
13
30 50
POF
HCS
8 TD
9 T
X
V
EE
7 TD
6 T
X
V
CC
5 R
X
V
CC
4
3 RD
2 RD
82 Ω
10 µF 0.1 µF
4.7 µH
0.1 µF
1 R
X
V
EE
+5 V ECL
SERIAL DATA
SOURCE
0.1 µF
0.1 µF
82 Ω
120 Ω120 Ω
+5 V ECL
SERIAL DATA
RECEIVER
4.7 µH
10 µF
+
+
+
–
5 V
82 Ω
82 Ω
120 Ω120 Ω
FIBER-OPTIC
TRANSCEIVER
SHOWN IN
FIGURE 1
4.7 µH
AVERAGE POWER – µW
0
200
100
0
DUTY CYCLE – %
20 40 80 100
150
50
60
AVERAGE POWER,
50% DUTY CYCLE
AVERAGE
MODULATED
POWER
6
Absolute Maximum Ratings
Parameter Symbol Min. Max. Unit Reference
Storage Temperature TS-40 85 °C
Operating Temperature TO-40 70 °C
Lead Soldering Temperature 260 °C Note 1
10 s
Transmitter High Level Forward IF,H 120 mA 50% Duty Cycle
Input Current ≥ 1 MHz
Transmitter Average Forward Input Current IF,AV 60 mA
Reverse Input Voltage VR3V
125 Megabaud Versatile Link
Transmitter
WARNING: WHEN VIEWED UNDER SOME CONDITIONS, THE OPTICAL PORT MAY
EXPOSE THE EYE BEYOND THE MAXIMUM PERMISSIBLE EXPOSURE RECOMMENDED
IN ANSI Z136.2, 1993. UNDER MOST VIEWING CONDITIONS THERE IS NO EYE HAZARD.
CAUTION: The small junction sizes inherent to the design of this component increase the component's suscepti-
bility to damage from electrostatic discharge (ESD). It is advised that normal static precautions be taken in
handling and assembly of this component to prevent damage and/or degradation which may be induced by
ESD.
HFBR-15X7 Series
Description
The HFBR-15X7 transmitters
incorporate a 650 nanometer LED
in a horizontal (HFBR-1527) or
vertical (HFBR-1537) gray
housing. The HFBR-15X7
transmitters are suitable for use
with current peaking to decrease
response time and can be used
with HFBR-25X6 receivers in data
links operating at signal rates
from 1 to 125 megabaud over 1
mm diameter plastic optical fiber
or 200 µm diameter hard clad
silica glass optical fiber. Refer to
Application Note 1066 for details
for recommended interface
circuits.
ANODE 1
CATHODE 2
GROUND 3
GROUND 4
GROUND
GROUND
SEE NOTE 6
Cycle Time
7
Electrical/Optical Characteristics 0 to 70°C, unless otherwise stated.
Parameter Symbol Min. Typ.[2] Max. Unit Condition Note
Transmitter Output PT-9.5 -7.0 -4.8 dBm IF,dc = 20 mA, 25°C Note 3
Optical Power, 1 mm POF -10.4 -4.3 0-70°C
Transmitter Output PT-6.0 -3.0 -0.5 dBm IF,d c = 60 mA, 25°C Note 3
Optical Power, 1 mm POF -6.9 -0.0 0-70°C
Transmitter Output PT-14.6 -13.0 -10.5 dBm IF,dc = 60 mA, 25°C Note 3
Optical Power, -15.5 -10.0 0-70°C
200 µm HCS®
Output Optical Power ∆PT-0.02 dB/°C
Temperature Coefficient ∆T
Peak Emission Wavelength λPK 640 650 660 nm
Peak Wavelength ∆λ 0.12 nm/°C
Temperature Coefficient ∆T
Spectral Width FWHM 21 nm Full Width,
Half Maximum
Forward Voltage VF1.8 2.1 2.4 V IF = 60 mA
Forward Voltage ∆VF-1.8 mV/°C
Temperature Coefficient ∆T
Transmitter Numerical NA 0.5
Aperture
Thermal Resistance, θjc 140 °C/W Note 4
Junction to Case
Reverse Input Breakdown VBR 3.0 13 V IF,dc = -10 µA
Voltage
Diode Capacitance CO60 pF VF = 0 V,
f = 1 MHz
Unpeaked Optical Rise tr12 ns IF = 60 mA Figure 1
Time, 10% - 90% f = 100 kHz Note 5
Unpeaked Optical Fall tf9nsI
F
= 60 mA Figure 1
Time, 90% - 10% f = 100 kHz Note 5
Notes:
1. 1.6 mm below seating plane.
2. Typical data is at 25°C.
3. Optical Power measured at the end of 0.5 meter of 1 mm diameter plastic or 200 µm diameter hard clad silica optical fiber with a large
area detector.
4. Typical value measured from junction to PC board solder joint for horizontal mount package, HFBR-1527. θjc is approximately 30°C/W
higher for vertical mount package, HFBR-1537.
5. Optical rise and fall times can be reduced with the appropriate driver circuit; refer to Application Note 1066.
6. Pins 5 and 8 are primarily for mounting and retaining purposes, but are electrically connected; pins 3 and 4 are electrically
unconnected. It is recommended that pins 3, 4, 5, and 8 all be connected to ground to reduce coupling of electrical noise.
7. Refer to the Versatile Link Family Fiber Optic Cable and Connectors Technical Data Sheet for cable connector options for 1 mm
plastic optical fiber and 200 µm HCS fiber.
8. The LED current peaking necessary for high frequency circuit design contributes to electromagnetic interference (EMI). Care must be
taken in circuit board layout to minimize emissions for compliance with governmental EMI emissions regulations. Refer to Application
Note 1066 for design guidelines.
8
HP8082A
PULSE
GENERATOR
50 OHM
LOAD
RESISTOR
HP54002A
50 OHM BNC
INPUT POD
HP54100A
OSCILLOSCOPE
BCP MODEL 300
500 MHz
BANDWIDTH
SILICON
AVALANCHE
PHOTODIODE
NORMALIZED SPECTRAL OUTPUT POWER
620
1.2
0.6
0
WAVELENGTH (nm)
630 650 670 680
1.0
0.2
660
70° C
0.8
0.4
640
25° C
0° C
Figure 2. Typical Spectra Normalized
to the 25°C Peak.
Figure 1. Test Circuit for Measuring
Unpeaked Rise and Fall Times.
Figure 3. Typical Forward Voltage vs.
Drive Current. Figure 4. Typical Normalized Output
Optical Power vs. Drive Current.
V
F
– FORWARD VOLTAGE – V
1
2.4
2.0
1.6
I
F,DC
– TRANSMITTER DRIVE CURRENT (mA)
10 100
1.8
70° C
2.2 25° C
0° C
P
T
– NORMALIZED OUTPUT POWER – dB
1
0
-15
-25
I
F,DC
– TRANSMITTER DRIVE CURRENT (mA)
10 100
-20 70° C
-5
0° C
-10
25° C
9
Absolute Maximum Ratings
Parameter Symbol Min. Max. Unit Reference
Storage Temperature TS-40 +75 °C
Operating Temperature T
A0 +70 °C
Lead Soldering Temperature 260 °C Note 1
10 s
Signal Pin Voltage VO-0.5 VCC V
Supply Voltage VCC -0.5 6.0 V
Output Current IO25 mA
125 Megabaud Versatile Link
Receiver
CAUTION: The small junction sizes inherent to the design of this component increase the component's suscepti-
bility to damage from electrostatic discharge (ESD). It is advised that normal static precautions be taken in
handling and assembly of this component to prevent damage and/or degradation which may be induced by
ESD.
HFBR-25X6 Series
Description
The HFBR-25X6 receivers contain
a PIN photodiode and
transimpedance pre-amplifier
circuit in a horizontal (HFBR-
2526) or vertical (HFBR-2536)
blue housing, and are designed to
interface to 1mm diameter plastic
optical fiber or 200 µm hard clad
silica glass optical fiber. The
receivers convert a received
optical signal to an analog output
voltage. Follow-on circuitry can
optimize link performance for a
variety of distance and data rate
requirements. Electrical
bandwidth greater than 65 MHz
allows design of high speed data
links with plastic or hard clad
silica optical fiber. Refer to
Application Note 1066 for details
for recommended interface
circuits.
1
2
GROUND
3
4
GROUND
GROUND SEE NOTES 2, 4, 9
GROUND
SIGNAL
V
CC
Cycle Time
10
Electrical/Optical Characteristics 0 to 70°C; 5.25 V ≥ VCC ≥ 4.75 V; power supply must be filtered
(see Figure 1, Note 2).
Parameter Symbol Min. Typ. Max. Unit Test Condition Note
AC Responsivity 1 mm POF RP,APF 1.7 3.9 6.5 mV/µW 650 nm Note 4
AC Responsivity 200 µm HCS RP,HCS 4.5 7.9 11.5 mV/µW
RMS Output Noise VNO 0.46 0.69 mVRMS Note 5
Equivalent Optical Noise Input PN,RMS - 39 -36 dBm Note 5
Power, RMS - 1 mm POF
Equivalent Optical Noise Input PN,RMS -42 -40 dBm Note 5
Power, RMS - 200 µm HCS
Peak Input Optical Power - PR-5.8 dBm 5 ns PWD Note 6
1 mm POF
-6.4 dBm 2 ns PWD
Peak Input Optical Power - PR-8.8 dBm 5 ns PWD Note 6
200 µm HCS
-9.4 dBm 2 ns PWD
Output Impedance ZO30 Ω50 MHz Note 4
DC Output Voltage VO0.8 1.8 2.6 V PR = 0 µW
Supply Current ICC 915mA
Electrical Bandwidth BWE65 125 MHz -3 dB electrical
Bandwidth * Rise Time 0.41 Hz * s
Electrical Rise Time, 10-90% tr3.3 6.3 ns PR = -10 dBm
peak
Electrical Fall Time, 90-10% tf3.3 6.3 ns PR = -10 dBm
peak
Pulse Width Distortion PWD 0.4 1.0 ns PR = -10 dBm Note 7
peak
Overshoot 4 % PR = -10 dBm Note 8
peak
Notes:
1. 1.6 mm below seating plane.
2. The signal output is an emitter follower, which does not reject noise in the power supply. The power supply must be filtered as in
Figure 1.
3. Typical data are at 25°C and VCC = +5 Vdc.
4. Pin 1 should be ac coupled to a load ≥ 510 Ω with load capacitance less than 5 pF.
5. Measured with a 3 pole Bessel filter with a 75 MHz, -3dB bandwidth.
6. The maximum Peak Input Optical Power is the level at which the Pulse Width Distortion is guaranteed to be less than the PWD listed
under Test Condition. PR,Max is given for PWD = 5 ns for designing links at ≤ 50 MBd operation, and also for PWD = 2 ns for
designing links up to 125 MBd (for both POF and HCS input conditions).
7. 10 ns pulse width, 50% duty cycle, at the 50% amplitude point of the waveform.
8. Percent overshoot is defined at: (V
PK - V100%)
–––––––––––– × 100%
V100%
9. Pins 5 and 8 are primarily for mounting and retaining purposes, but are electrically connected. It is recommended that these pins be
connected to ground to reduce coupling of electrical noise.
10. If there is no input optical power to the receiver (no transmitted signal) electrical noise can result in false triggering of the receiver.
In typical applications, data encoding and error detection prevent random triggering from being interpreted as valid data. Refer to
Application Note 1066 for design guidelines.
11
Figure 1. Recommended Power Supply Filter Circuit.
Figure 2. Simplified Receiver Schematic.
Figure 3. Typical Pulse Width
Distortion vs. Peak Input Power. Figure 4. Typical Output Spectral
Noise Density vs. Frequency. Figure 5. Typical Rise and Fall Time
vs. Temperature..
Versatile Link Mechanical Dimensions
Versatile Link Printed Circuit Board Layout Dimensions
HORIZONTAL MODULES
HFBR-1527
HFBR-2526
HORIZONTAL MODULES
HFBR-1537
HFBR-2526
HFBR-15X7
www.semiconductor.agilent.com
Data subject to change.
Copyright © 1999 Agilent Technologies, Inc.
Obsoletes 5962-9376E (4/94)
5965-6114E (11/99)
