Optic Fibre Communication System

8/3/2019 Optic Fibre Communication System

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OPTIC FIBRE COMMUNICATION SYSTEM

DONE BY: GUIDED BY:

ANJUS ANU ANAND ASHA JOHNMs.SumoI.N.C Mr. Asini.H

ABSTRACT

The circuit for OPTIC FIBRE COMMUNICATION SYSTEM is designed to

demonstrate the transmission and reception of a digital data through an optic fibre cable. The

optic signals generated by the transmitter circuit are received by the optical receiver circuit

after transmission through an optic fibre cable.This communication is much more effective

than ordinary communication. It provides bandwidth in the GHz range.lt

provides minimum

transmission loss. It finds many applications in communication systems, measuring systems,

industrial, medical and military applications.

http://range.lt/

http://range.lt/

http://range.lt/



CONTENTS

o INTRODUCTION

o BLOCK DIAGRAM

o BLOCK DIAGRAM EXPLANATION

o CIRCUIT DIAGRAM

o CIRCUIT DIAGRAM EXPLANATION

o PCB DESIGNING AND FABRICATION

o PCB LAYOUT

o PCB SCHEMATIC

o COMPONENTS LIST

o CONCLUSION

o REFERENCES

o DATASHEETS

INTRODUCTION

This project done on communication using optic fibres

can be used for data transmission over small distances in computer

networks, closed circuit T.V s etc. The information carrying capacity

is directly proportional to the frequency or bandwidth of the carrier

wave. This system uses light as a carrier wave in the frequency range

10A13 Hz to 10 A16 Hz. Hence information transmission capacity

increases by several order of magnitude.Thus it overcome almost all



the drawbacks of communication systems involving electrical

signals.

BLOCK DIAGRAM EXPLANATION

The block diagram given in the figure shows a basic opticfibre communication system.lt mainly consists of three elements

1) Optical transmitter 2) The optic fibre cable3) The optical receiver

This general description is appropriate for analog as well asdigital communication systems.Fibre optic technology and communicationtechnology are involved in this system.

1) The optical transmitter It consists of electronic components which convert the electrical

signals into corresponding optical signals. The data in the form of electricalsignal is provided to drive the circuit. This is achieved by using an astablemultivibrator which generate a series of digital data in the form of ones andzeroes. This signal is used to turn ON and OFF an LED.This is done bymeans of a transistor switching circuit.The electrical signals are convertedinto light signals by an optical source consisting of an LED. These lightsignals are then transmitted through the optic fibre cable. The LED provideslight of constant wavelength and low transmission loss. The light injected

into the OFC is a faithful representation of the information.

2) The optic fibre cableIt consists of glass fibres which act as wave guide for optical signal. For

long distance transmission^ or more fibres are joined together. The opticfibre is made of three layers namely core, cladding and protectivecovering.Optic fibre works on the principle of total internal reflection.

3) The optical receiver It consists of a photo detector, amplifier and a signal indicator. The

photodetector converts optical signal into corresponding electrical signal.Here an LDR is used to detect the incoming light signals. The amplifier amplifies the signal. An LED is used to indicate the reception of the data.

http://system.lt/

http://system.lt/



TRANSMITTER

CIRCUIT DIAGRAM



RECEIVER

CIRCUIT DIAGRAM EXPLANATION

OPTICAL TRANSMITTER

The circuit for a basic optic fibre communication system for

transmitting a series of digital data is shown in the figure. For the purpose of

generating the digital signals, an astable multivibrator is designed.

When the circuit is connected as shown in the above figure(pin 2 and

6) connected it triggers itself and free runs as a multivibrator.The external

capacitor charges through Rl and R2 and discharges through R2 only. Thus the

duty cycle may be precisely set by the ratio of these two resistors. In the astable

mode of operational charges and discharges between 1/3 Vcc and 2/3 Vcc. As in

the triggered mode ,the charge and discharge times are therefore frequency are

independent of the supply voltage.

The charge time(output high) is given by: tl=.693(Rl+R2)Cl And the

discharge time (output low) by : t2=0.693(R2)Cl Thus the total period

t is given by : T=tl+t2= 0.693(R1+2R2)C1 The frequency of



oscillation is then : f=l/T=1.44/(Rl+2R2)Cl The duty cycle is given by

:D=R2/R1+2R2

The output signals thus produced by the astable multivibrator is fed to a

transistor switching circuit.For this a BF 194 transistor is used.

Switching circuit

An LED is connected to the collector of the transistor which will be turned ON

and OFF according to the input digital data. As the input to the base of the

transistor goes high ,the transistor switches to saturation. Current passes through

the transistor and therefore LED glows. As the input to the transistor goes low

,the transistor switches to cut off and therefore LED doesn't glow.

Superluminiscent LEDs are used here. For proper operation of astable

multivibrator ,a +10 V supply and for the switching circuit a +5V supply is

used. The LED thus produces the optical signals which are to be transmitted.

The LED is coupled to the OFC by means of suitable coupler without any loss

of data.Thus the signal is effectively transmitted through the OFC. OPTIC

FIBRE CABLE

Here multimode type OFC is used. The OFC is made from silica glass.

A plastic coating is also provided. They have larger numerical aperture to

facilitate efficient coupling to inherent light sources such as light emitting

diodes. They provide bandwidth in the GHz range.

Optic fibre works on the principle of total internal reflection of light.

When a ray of light passes from a dielectric medium of refractive



index nl (denser) to other of refractive index n2(rarer) ,and when the angle of

incidence is critical angle e, then the refracted ray in the fibre just grazes the

surfaces separating the two medium.ie the angle of refraction becomes

90°.When the angle of incidence becomes greater than critical angle, the light

ray gets totaly internally reflected into the same medium. This phenomenon is

called total internal reflection. Any light ray incident on the fibre edge at an

angle greater than 0a meets the core cladding interface at an angle less than

critical angle and will not be totally internally reflected and transmitted. Only

the light rays that enter the fibre edge within the angle Oa will be accepted by

the fibre for total internal reflection. Thus this angle of incidence 0a is called the

acceptance angle. The numerical aperture of a fibre deopends on the acceptance

angle 0a by the relation Sin Oa=NA.

Optic fibres are very light and easy to handle. Using these the hazards

due to short circuit can be avoided. It is also ideal for secret communication

because it is very difficult to tap. Optic fibres are unaffected by outdoor

atmospheric conditions like lightning. Besides there is no possibility of spark

from broken fibre. It will not corrode and is unaffected by most chemicals. They

are also immune to electromagnetic interference and avoid crosstalk.Also

transmission losses are very low.

OPTICAL RECEIVER



The light transmitted through the OFC has to be properly received.

For this optical signal has to be converted into corresponding electrical form . To

perform this optical detectors are used. Here an LDR is used for this purpose. The

OFC is effectively coupled to the LDR without lossage of incoming data. The

LDR is placed in the biasing circuit of the transistor BF547.As the incoming signal

goes high, the resistance of the LDR goes low. Current flows and proper biasing is

achieved. The transistor then switches to saturation. An LED is connected at the

collector of the transistor as an indicator of the incoming signal. As the transistor

switches to saturation, current flows and LED glows. When the incoming signal

goes low ,the resistance of the LDR becomes high. Current doesn't flow.

Transistor switches to cut off and therefore the LED turns OFF. Thus the data has

been effectively transmitted from the transmitter circuit to the receiver.

This circuit forms the basis of all optic fibre systems.

POWER SUPPLYA regulated power supply is an electronic circuit that is

designed to provide a constant dc voltage of predetermined value across load

terminals irrespective of ac mains fluctuations or load variations. It mainly

consists of an ordinary power supply and a voltage regulating device

The system requires a regulated +5 v supply for the switching

circuit and a +10V supply for the astable multivibrator. A +5V supply is also

needed for the receiver circuit. These can be delivered from the 230V domestic

supply. Before applying this to the system we must step down this high voltage to

an appropriate value. After that it should be rectified. This will provide a



unidirectional current. To achieve a +5V DC we should regulate this. All these are

done in power supply circuitry, which is explained below.

A 12-0-12 V step down transformer is connected to provide the

necessary low voltage. The transformer also works as an isolator between the hot

and cold end. The hot end refers to the 230 V supply, which is a hazardous one,

and the cold one refers to the safe, low voltage. Now the hot portion appears only

at the primary of the transformer.The secondary of the transformer deliver 12 V ac

pulses along with a ground. This ac supply goes to a center tap rectifier, which

converts the ac into a unidirectional voltage.The ripples in the resulting supply is

filtered and smoothed by a 2200 microfarad /25V capacitor. The 0.1 microfarad

capacitor bypasses any



high frequency noises.The resulting supply has the magnitude above 17 V. This

voltage is fed to the regulator IC 7805 and 7810.This IC 7805 provides a

regulated 5V positive supply at its 3rdpin.The required input for this is more than

7.5 V. The IC 7810 provides a regulated 10V positive supply at its 3 rd pin

Device Output Maximum Minimumtype voltage in input input

volts voltage in voltage in

volts volts7805 +5 35 7.37810 +10 35 12.5



PCB DESIGNING AND FABRICATION

DESIGN AND PCB FABRICATION

The PCB consists of an insulating base materialon which copper conductors are etched by photolithography or screen printing.The insulating materials provides electrical isolation and mechanical rigidity for the printed conductors as such it should possess the essential electrical andmechanical properties and good flexural strength, reasonable high temperaturewith standing capability, low moisture absorption warpage, good merchantability,good electrical resistance, high dielectric strength, low dielectric constant, lowdissipation factor etc.

PHOTOGRAPHIC METHOD OF PCB FABRICATIONPhotographic method is another commonly used PCB fabrication

method. It is more expensive and widely used for massive production.

SCREEN PRINTINGIn this method, a mesh is prepared and is placed over the copper

sheets. Screen printing material is pasted over the areas where the circuit is to beland. All other areas are kept open. The different steps used in PCB fabrication arelisted below :-

Cutting copper clad lamination

The copper clad laminates are manufactured in 4 inch*3 inch size.From this sheet pieces are cut off to the required size using a shearing machine.For the purpose of handling the PCB during fabrication, borderline of PCB. Henceatleast cutting PCB provides 10 mm of additional space from the actual requiredPCB size.

CleaningThe copper oxides may build up on the copper surface. Inorder to

remove this following procedure is required :-a) Wipe with cotton wool socked in trichloro ethylene

b) Dipping in 10% HC1 for 1 minute at room temperature.c) Scrub with pumice powder.

PCB LAYOUT

TRANSMITTER



PCB SCHEMATIC



CONCLUSION

This circuit can be considered as the basis for all systems utilizing

the optic fibre technology. The project explains the transmission of data

through an optic fibre cable. Optic fibre sensors like smoke or pollution

detector,LDV,crack sensors etc has wide usage today. Besides optic fibres

finds many applications in telecommunication, LAN networks, industrial

applications like horoscope and remote sensing, medical applications, military

applications like antitank missile system, secret communication links etc. It is

expected that Photonics ,the light based systems rather than electronics, the

electron flow devices will dominate in the coming years.



NE555 SA555 -SE555

GENERAL PURPOSE SINGLE BIPOLAR TIMERS

LOW TURN OFF TIME

MAXIMUM OPERATING FREQUENCYGREATER THAN 500kHzTIMING FROM MICROSECONDS TO HOURSOPERATES IN BOTH ASTABLE ANDMONOSTABLE MODESHIGH OUTPUT CURRENT CAN SOURCE ORSINK 200mAADJUSTABLE DUTY CYCLE TTLCOMPATIBLETEMPERATURE STABILITY OF 0.005% PER°C

DESCRIPTION

The NE555 monolithic timing circuit is a highly stablecontroller capable of producing accurate time delaysor oscillation. In the time delay mode of operation,the time is precisely controlled by one external re-sistor and capacitor. For a stable operation as an os-cillator, the free running frequency and the duty cy-cle are both accurately controlled with two externalresistors and one capacitor. The circuit may be trig-gered and reset on falling waveforms, and the outputstructure can source or sink up to 200mA. TheNE555 is available in plastic and ceramic minidippackage and in a 8-lead micropackage and in metalcan package version.

D S08(Plastic Micropackage)

PIN CONNECTIONS (top view)

c 1 J 8

J 1 - GND2 - Trigger

L~

2 7 J 3 - Output4 - Reset5 - Control voltage

L~

3 6 1 6 - Threshold7 - Discharge8 -Vcc

C 4 5 J

14/10

N DIP8(Plastic Package)

TemperaturePackageNumberRange5NE555o°c,70°C•SA555 |

^o°c105°C•| SE555 |-55°C125°C•

ORDER



NE555/SA555/SE555

BLOCK DIAGRAM

R1 4.7kR2 R3 8304.7k

R12 6.8k

Q 5^|-*-£ Q6 Q7^| • JoB Q9^019 *1 f

IQ2C

J Q2

i---1

THRESHOLD

o [,Q1

Q

J[011 Q12 J5k

R14220 >

TRIGGER o

RESET O

DISCHARGE Oroi 5

[QIC

• _ . Q16J •

r o ,7

R15

7k"1 i

014R5 10k R6 n 1 r7 n 1

100k 100k

IGND °

TRIGGER COMPARATOR

ABSOLUTE MAXIMUM RATINGS

Symbol Parameter Value UnitVcc Supply Voltage 18 V

::=- Operating Free Air Temperature Range for NE555for SA555 for SE555

0to 70 -40 to105 -55 to 125 °c

Tj Junction Temperature 150 °cStorage Temperature Range -65 to 150 °c

OPERATING CONDITIONS

Symbol Parameter SE555 NE555 - SA555 UnitVcc Supply Voltage 4.5 to 18 4.5 to 18 V

Vthi Vttjg, V C|, V rese t Maximum Input Voltage Vcc Vcc V

ELECTRICAL CHARACTERISTICS

THRESHOLD-CONTROL VOLTAGE "

SCHEMATIC DIAGRAM

CONTROLVOLTAGE

THRESHOLD

COMPARATOR

Vcc'O



NE555/SA555/SE555

Tamb = +25°C, Vcc = +5V to +15V (unless otherwise specified)Symbol Parameter SE555 NE555 - SA555 Unit

Min. Typ. Max. Min. Typ. Max.Ice Supply Current (R L °°) (- note 1) Low State

VCc = +5VVcc = +15V High State VCc = 5V

3 10 2 5 12 3 10 2 6 15 mA

Timing Error (monostable) (R A= 2k to 100kfl,C = 0.1 uF) Initial Accuracy - (note 2) Driftwith Temperature Drift with Supply Voltage

0.5 300 .05

2100 0 .2

150 0.1

30.5

%

ppm/°C%N

Timing Error (astable)(R A, R B = ika to lookn, c = o .iuF,Vcc = +15V) Initial Accuracy - (note 2) Driftwith Temperature Drift with Supply Voltage

1 .5 900 .15

2.25150 0.3

%

ppm/°C%/V

VCL Control Voltage levelVcc = +15V Vcc = +5V

9.62 .9

103.33

10 .4 3 .8 92 .6

10 3.33 11 4 V

Vth Threshold VoltageVCC = +15V Vcc = +5V

9.4 2 .7 10 3.33 10 .6 4 8.8 2 .4 10 3.33 11.2 4 .2 V

Ith Threshold Current - (note 3) 0 .1 0.25 0 .1 0 .25 uAvtrig Trigger Voltage

Vcc = +15V Vcc = +5V4 .8 1 .45 5 1 .67 5 .2 1.9 4.5 1.1 5 1 .67 5.6 2.2 V

■trig Trigger Current (Virig = 0V) 0.5 0.9 0.5 2 .0 HA

Vreset Reset Voltage - (note 4) 0.4 0.7 1 0.4 0.7 1 V

I reset Reset CurrentVreset = +0.4V Vreset = 0V

0 .1 0.4 0.4 1 0 .1 0.4 0.4 1 .5 mA

VOL Low Level Output Voltage Vcc = +15V,l0(sink)= 10mA lo(sink) = 50mA lo(sink) = 100mAlo(sink) = 200mA Vcc = +5V, lo(sink) = 8mAlO(sink) = 5mA

0.1 0.4 22 .5 0 .1

0 .05

0 .15 0.52.2

0.25 0 .2

0 .1 0.4 22 .5 0.3

0 .25

0 .250.75 2 .5

0.40.35

V

VOH High Level Output VoltageVcc = +15V, lo (source) = 200mA lo(source) =100mA Vcc = +5V, lo(source) = 100mA

13 3 12 .513 .3 3.3

12 .752 .75

12 .513 .3 3.3

V

Notes: 1. Supply current when output is high is typically 1mA less.2. Tested at Vcc = +5V and Vcc = +15V.3. This will determine the maximum value of R A + RB for +15V operation the max total is R = 20M£2 and for 5V operation

the max total R = 3.5M12.

3/10



NE555/SA555/SE555

ELECTRICAL CHARACTERISTICS (continued)

Figure 4 : Low Output Voltage versus OutputSink Current

0.01

17/10

SymbolParameterSE555NE555 - SA555Unit

Min.Typ.Max.Min.Typ.Max.Idis(off)Discharge Pin Leakage Current (output high) (Vdis

=10V)2010020100nAVdis(sat)Discharge pin Saturation Voltage (output low) - (note 5)

Vcc = +15V, Idis = 15mA Vcc = +5V, Idis = 4.5mA180 80480 20018080480 200mVtr tfOutput Rise Time Output Fall Time100 100200

200100 100300 300nstoffTurn off Time - (note 6) (VreS

et =

Vcc)0.50.5US Notes : 5. No protection against excessive Pin 7 current is necessary, providing the package dissipation rating will not be exceeded. 6. Time mesaured from a positivegoing input pulse from 0 to 0.8x Vcc into the threshold to the drop from high to

low of the output trigger is tied to treshold.

Figure 1 : Minimum Pulse Width Required for Figure 2 : Supply Current versus SupplyVoltage

Trigering O-SilS 0-5416

0 0.1 0.2 0.3 V, (V) 5 10 15VjIV)

Figure 3 : Delay Time versusTemperature c-

5026

- 50 -25 0 2550 75 l

am b('C)

Vjr5V -55 -c/ JS-c// 125'C

g-sit7

1 2 5 10 20lsiNK ,rnA '

0.1



NE555/SA555/SE555



v s= 10V

2S*C----------------ZS'C ---------------

55'C -

2 5 10 20 'SINK 1" 1*1

Figure 7 : High Output Voltage Drop versusOutput

Figure 8 : Delay Time versus Supply Voltage

18/10

-55-cn

1 2 5 10 20l

5INK lmAI

(V)

0.1



NE555/SA555/SE555

19/10

1

25-<125'C, V«V M1

G-S42Q

1 I\\\-

G-SOZS

0 5 10 15V

S(V)

5 10 20 'SOURCE 1"1*'



NE555/SA555/SE555

APPLICATION INFORMATION

MONOSTABLE OPERATION In the monostablemode, the timer functions as a one-shot. Referring tofigure 10 the external capacitor is initially helddischarged by a transistor inside the timer.

Figure11

The circuit triggers on a negative-going input signalwhen the level reaches 1/3 Vcc. Once triggered, thecircuit remains in this state until the set time haselapsed, even if it is triggered again during this in-terval. The duration of the output HIGH state is givenby t = 1.1 R1C1 and is easily determined by figure 12.Notice that since the charge rate and the thresholdlevel of the comparator are both directly proportionalto supply voltage, the timing interval is independentof supply. Applying a negative pulse simultaneouslyto the reset terminal (pin 4) and the trigger terminal

(pin 2) during the timing cycle discharges the exter-nal capacitor and causes the cycle to start over. Thetiming cycle now starts on the positive edge of thereset pulse. During the time the reset pulse in ap-plied, the output is driven to its LOW state. When anegative trigger pulse is applied to pin 2, the flip-flopis set, releasing the short circuit across the externalcapacitor and driving the output HIGH. The voltageacross the capacitor increases exponentially with thetime constant x = R1C1. When the voltage across thecapacitor equals 2/3 V cc , the comparator resets theflip-flop which then discharge the capacitor rapidlyand drivers the output to its LOW state.

Figure 11 shows the actual waveforms generated inthis mode of operation.

When Reset is not used, it should be tied high toavoid any possibly or false triggering.

10 100 1.0 10 100 10 (td) us us ms ms mss

ASTABLE OPERATIONWhen the circuit is connected as shown in figure 13(pin 2 and 6 connected) it triggers itself and free runsas a multivibrator. The external capacitor charges

through Ri and R2 and discharges through R2only.

20/10

INI1'UT =1

• 2.0'//divOUTPU1' vo-TACiE=5.0Vdiv /<r 1

t = 0.1 rns/ div

CAPACITOR VOLTAGE = 2.0V/div

Figure10

R1 = 9.1kQ, C1 = 0.01uF, R|_= 1kQ

Figure 12



NE555/SA555/SE555

Thus the duty cycle may be precisely set by the ratioof these two resistors.In the astable mode of operation, C1 charges anddischarges between 1/3 Vcc and 2/3 Vcc. As in thetriggered mode, the charge and discharge times andtherefore frequency are independent of the supplyvoltage.

21/10



Figure 13 Figure 15 : Free Running Frequency versus Ri,R 2 and Ci

PULSE WIDTH MODULATOR When the timer isconnected in the monostable mode and triggered witha continuous pulse train, the output pulse width canbe modulated by a signal applied to pin 5. Figure 16

shows the circuit.

Figure 16 : Pulse Width Modulator.

D =Ri +2R 2

-O Vcc*

Figure 14

Output O

Figure 14 shows actual waveformsgenerated in this mode of operation.The charge time (output HIGH) is given by: ti = 0.693 (Ri + R 2) Ci and the dischargetime (output LOW) by: t

2= 0.693 (R

2) Ci

Thus the total period T is given by : T = ti+ tz = 0.693 (Ri + 2R2) Ci The frequencyofoscillation is them :

f =

^=

1.44 ~ T ~(Ri + 2R

2) Ci and may be easily found by

figure 15. The duty cycle is given by: R 2

c(tiF)10

1.0

0.1

0.01

QSO-

0.000.1 1 10 100 1k 10k f 0(Hz)

Trigger O-------- 2

ouTPU"r voLTAC3E =5.0V'div/V

/V/V)V/\acii"or 1"age= 1OV/dV

t = 0.5ms / div

= 4.8kfl, C1= 0.1uF, R L=1kQ

NE555



NE555/SA555/SE555

LINEAR RAMPWhen the pullup resistor, R A, in the monostable cir-cuit is replaced by a constant current source, alinear ramp is generated. Figure 17 shows a circuitconfiguration that will perform this function.

Figure 17.

Figure 18 shows waveforms generator by the linear ramp.The time interval is given by :

(2/3 Vcc RE (R I+ R 2) C Ri Vcc - VBE (R I+ R2>

Figure 18 : Linear Ramp.50% DUTY CYCLE OSCILLATORFor a 50% duty cycle the resistors R A and R E maybe connected as in figure 19. The time preriod fortheoutput high is the same as previous,ti = 0.693 R A C.

For the output low it is t .2 =

[(RARB)/(R A + R B)] CLn 1

2R B - R A

Thus the frequency of oscillation is f ,ti + t 2

Note that this circuit will not oscillate if R B is greater

Figure 19 : 50% Duty Cycle Oscillator.

than 1/2 R A because the junction of R A and R B can-not bring pin 2 down to 1 13 Vcc and trigger thelower comparator.

ADDITIONAL INFORMATION Adequate power supply bypassing is necessary to protect associatedcircuitry. Minimum recommended is 0.1 u.F inparallel with 1uP electrolytic.

Vcc = 5V Top trace : input 3V/DIVTime = 20us/DIV Middle trace : output 5V/DIVRi = 47kfl Bottom trace : output 5V/DIVR2 = 100kfl Bottom trace : capacitor voltageRe = 2.7k£2 1V/DIVC = 0 .01N .F

Dn i i n tn

[ 8 5 I 1

u_

23/10

■O Vcc'

Output o

T = VBE = 0.6V

-i

PACKAGE MECHANICAL DATA8 PINS - PLASTIC DIP

e4



NE555/SA555/SE555

4

Dimensions Millimeters InchesMin. Typ. Max. Min. Typ. Max.

A 3.32 0.131

a1 0.51 0.020

B 1.15 1.65 0.045 0.065

b 0.356 0.55 0.014 0.022

b1 0.204 0.304 0.008 0.012

D 10.92 0.430

E 7.95 9.75 0.313 0.384

e 2.54 0.100

e3 7.62 0.300

e4 7.62 0.300

F 6.6 0260

i 5.08 0.200

L 3.18 3.81 0.125 0.150

Z 1.52 0.060

ti

u u u uDimensions Millimeters Inches

Min. Typ. Max. Min. Typ. Max.A 1.75 0.069

a1 0.1 0.25 0.004 0.010

a2 1.65 0.065

a3 0.65 0.85 0.026 0.033

b 0.35 0.48 0.014 0.019

b1 0.19 0.25 0.007 0.010

C 0.25 ______0.5 0.010 0.020

d 45° (typ.)D 4.8 5.0 0.189 0.197

E 5.8 6.2 0.228 0.244

e 1.27 0.050

e3 3.81 0.150

F 3.8 4.0 0.150 0.157

L 0.4 1.27 0.016 0.050

M 0.6 0.024

24/10

e3

PACKAGE MECHANICAL DATA8 PINS - PLASTIC MICROPACKAGE (SO)



NE555/SA555/SE555

S 8° (max.)

Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for theconsequences of use of such information nor for any infringement of patents or other rights of third parties which may result fromits use. No license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specificationsmentioned in this publication are subject to change without notice. This publication supersedes and replaces all informationpreviously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics.

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Documents

Optic Fibre Communication System