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.
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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
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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.
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TRANSMITTER
CIRCUIT DIAGRAM
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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
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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
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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
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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
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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
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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
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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
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PCB SCHEMATIC
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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.
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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
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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
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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
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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
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NE555/SA555/SE555
Figure 5 : Low Output Voltage versus OutputSink Current
Figure 6 : Low Output Voltage versus OutputSink Current
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
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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*'
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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
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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
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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
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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
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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)
8/3/2019 Optic Fibre Communication System
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NE555/SA555/SE555
S 8° (max.)
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