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DIGITAL STOP WATCH
Group members
Syed Talha Mairaj : ID 9457
Adi Samama : ID 9359
Shahzaib Umer : ID 9346
Class Id :100616
Department of Electrical Engineering
PAF-KIET, Karachi
ABSTRACT:
We use Stopwatches for many purpose.Particularly it uses in different competition and sports activities .
Stopwatches may be analog or may digital . We use Stopwatches to find out how much time we take to
do any activity. Mostly we use digital version of stopwatches because it is more accurate as compared
to analog version of stopwatches and it is very easy to use .
We made this stopwatch to observe the
accuracy and reliability of it.
This Stopwatch can count approximately up to 9 minutes and 59.9 seconds . It is accurate upto 0.1
seconds . This circuit is very easy and simple to understand . The most important part of this circuit is
(multi-vibrator) which followed by 7-segment decoder stages and counter . we use voltage regulator to
convert 9 volts to 5 volts .
INTRODUCTION:
DIGITAL STOPWATCHES:
We choosed thir project because it covers all the aspects of our course Digital Logic Fundamentals
(DLF) . Particularly we choose it to observe and realize the working of Multivibrator and 7-segment
Decoder . Oyur aim is to implement our knowledge practically and observe that what we have learned
from this course . This stopwatch is use in small time intervals competitions . This stopwatch has several
different functions including pause which represents both start & stop , reset . I think this project will
improve our teamwork , our skills and help us to gain more experience in working together . The class
lectures was very helpful with thus project because it covered important topics such as multiplexers ,
decoders , counters and 7- segment display .
555 timer IC is used to provide the time delays, as an oscillator , and as a flipflop element .
(2) In this circuit we used 7 segment displays for displaying the decimal numbers or numerals.
(3) 4033 IC is used in digital display . It has a 5 stage decade counter with decodr which convert
the code to a 7 segment decoded output which can be seen by the help of 7 segment display.
THEORETICAL TREATMENT:
CONSTRUCTION:
COMPONENTS & ECONOMICS:
In this project we are used simple components:
PART UNIT PRICE (PKR) NOS. TOTAL PRICE
7- segment common cathode 40 4 160
555-timer IC 10 1 10
4033 IC 50 4 200
