HP HFBR-1537, HFBR-1527, HFBR-2536, HFBR-2526, HFBR-0507 Datasheet

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 Inexpensive, Easily Terminated Plastic Optical Fiber, and with Large Core Silica Fiber

•High Voltage Isolation

•Transmitter and Receiver Application Circuit Schematics 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, HFBR25X6. 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 components 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

HFBR-0507 Series

HFBR-15X7 Transmitters

HFBR-25X6 Receivers

and 200 μm Hard Clad Silica (HCS®) fiber. With the recommended drive circuit, the LED operates at speeds from 1-125 MBd. The HFBR-25X6 is a high bandwidth analog receiver containing a PIN photodiode and internal transimpedance amplifier. With the recommended application 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.

HCS® is a registered trademark of Spectran Corporation.

5965-6114E (1/97)

17

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 Hewlett-Packard 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

TA

0

70

°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

VIH

VCC -1.06

VCC -0.70

V

Data Output Load

RL

45

55

Ω

Note 1

Signaling Rate

fS

1

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.

18

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%)	tr	2.1	ns	5 MHz
Optical Fall Time (90% to 10%)	tf	2.8	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

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%)	tr	3.1	ns	5 MHz
Optical Fall Time (90% to 10%)	tf	3.4	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.

19

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 Ω	Note 5
Data Output Voltage - High	VOH	VCC -0.9	V	RL = 50 Ω	Note 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.

L1
CB70-1812	VCC

				C1				C2							14		C3	C4		C5	+			C6	C7
				0.001		R5		0.1									0.1	0.001		10				0.1	0.001
														9
						22											8									8
														10	U1C										1
														7 74ACTQ00											2	U2
																						R8*			3
						Q1		Q2						12											4
																	11									5 HFBR-15X7
						BFQ52		BFQ52		1				13	U1D			Q3
																						R9*
											U1A	3			74ACTQ00			2N3904
										2
						R6	R7				74ACTQ00
														4			6
						91	91
														5	U1B
	TX VEE																					R10
9															74ACTQ00			C8*
	Q2 BASE																					15			R11*
8
7	Q1 BASE
	TX VCC
6	RX VCC		+
5		C20		C19																			ALL CAPACITOR VALUES
4	NC	10		0.1														R12
	PIN 19 10H116																						ARE IN MICRO FARADS,
3	PIN 18 10H116					VBB								VCC			C10	4.7	C9				WITH 10% TOLERANCE
2	RX VEE																0.1		.47				(UNLESS OTHERWISE NOTED).
J1 1													3V
										C17													ALL RESISTANCES ARE IN
					R22									VBB
											0.1												OHMS WITH 5% TOLERANCE
				R24	1K													R13					(UNLESS OTHERWISE NOTED).
				1K				R18				R16						4.7
								51				51					R14				8
			MC10H116FN				C16	MC10H116FN				MC10H116FN					1K
																		C12
							0.1		10					14
			18		15			4			7		9			13		0.1	1
			19	U4C	17			3	U4A		5		8	U4B		12			2		U3
																			3
						C15	R19		20	2		R17					R15	C11	4
						0.1	51					51					1K	0.1			5	HFBR-25X6
				R25		R23							3 V
				1K				R20			VCC
						1K																THE VALUES OF R8, R9, R11, AND
						VBB		12									VBB					C8 ARE DIFFERENT FOR POF AND
																						HCS DRIVE CIRCUITS.
				C18				R21					+ C14				C13					R8		POF	HCS	TOLERANCE
													10											300	82	1%
				0.1				62	U5								0.1					R9		300	82	1%
																						R11		1K	470	1%
											TL431											C8		43 pF	120 pF	1%

Figure 1. Transmitter and Receiver Application Circuit with +5 V ECL Inputs and Outputs.

20