The following content consists of the brief details about the topic
INTRODUCTION
CONCEPT OF ASTABLE MULTI VIBRATOR
CONCEPT OF DECADE COUNTER IC4017
CIRCUIT EXPLANATION
CIRCUIT DIAGRAM
VIDEO OF CIRCUIT WORKING
WORKING OF CIRCUIT
INFERENCE
REFERENCE
SIMULATION OF AN ELECTRONIC DICE CIRCUIT USING LEDs IN PROTEUS SOFTWARE
1. SIMULATION OF AN ELECTRONIC DICE CIRCUIT
USING LEDs IN PROTEUS SOFTWARE
PRESENTED BY
VAISHALI.K
M.Tech(ECE)-Ist yr
Reg.No.21304023
DEPARTMENT OF ELECTRONICS ENGINEERING
PONDICHERRY UNIVERSITY
SUBMITTED TO
Dr .K.ANUSUDHA,
Assistant Professor,
Dept.Of Electronics Engineering
2. AGENDA
INTRODUCTION
CONCEPT OF ASTABLE MULTI VIBRATOR
CONCEPT OF DECADE COUNTER IC4017
CIRCUIT EXPLANATION
CIRCUIT DIAGRAM
VIDEO OF CIRCUIT WORKING
WORKING OF CIRCUIT
INFERENCE
REFERENCE
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3. INTRODUCTION
• The basic idea of the project about introducing some new
technique of rolling dice into a game .The traditional method
sometimes go unfair and ultimately the game gets spoiled.
Keeping the issue in mind, an unbiased electronic dice is
designed.
• Simply pushing a button in electronic dice brings fast blink of
six LEDs representing six number of dice and ultimately
leaving behind anyone number of dice as result through the
corresponding LED glown.
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4. INTRODUCTION
• The extent of fairness of the game is highly secured as the
blinking rate can be regulated by changing the value of
variable resistor used. The practicality of the circuit design is
assured by its simple design and compact size, also way of
usage.
• IC 555 used here in the form of astable multi-vibrator so that
patterned is never observable and a fair game can be
executed. IC CD4017 works as a decade counter.
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5. CONCEPT OF ASTABLE MULTI
VIBRATOR
• A multi-vibrator is a device that switches between two states.
• It is a type of oscillator and can be used as a trigger, converter,
moderator, or divider.
• It usually produces changes in a system at timed intervals,
depending on the number and placement of resistors and
other elements within the system as well as the input signal’s
intensity.
• An astable multi-vibrator is a multi-vibrator that does not rest
in an unstable state like other multi-vibrators, but
continuously switches between two states.
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6. WORKING PRINCIPLE OF ASTABLE
MULTI-VIBRATOR
• Astable multi-vibrator is also called
as Free Running Multi-vibrator.
• It has no stable states and
continuously switches between the
two states without application of
any external trigger.
• The IC 555 can be made to work as
an astable multi-vibrator with the
addition of three external
components: two resistors (R1 and
R2) and a capacitor (C).
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7. WORKING PRINCIPLE OF ASTABLE
MULTI-VIBRATOR
• The pins 2 and 6 are connected and hence there is no need
for an external trigger pulse.
• It will self trigger and act as a free running multivibrator. The
rest of the connections are as follows: pin 8 is connected to
supply voltage (VCC).
• Pin 3 is the output terminal and hence the output is available
at this pin. Pin 4 is the external reset pin.
• A momentary low on this pin will reset the timer. Hence when
not in use, pin 4 is usually tied to VCC.
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8. WORKING PRINCIPLE OF ASTABLE
MULTI-VIBRATOR
• The control voltage applied at pin 5 will change the threshold
voltage level.
• But for normal use, pin 5 is connected to ground via a
capacitor (usually 0.01µF), so the external noise from the
terminal is filtered out. Pin 1 is ground terminal.
• The timing circuit that determines the width of the output
pulse is made up of R1, R2 and C.
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9. OPERATION
• The following schematic depicts the internal circuit of the IC
555 operating in astable mode. The RC timing circuit
incorporates R1, R2 and C.
• Initially, on power-up, the flip-flop is RESET (and hence the
output of the timer is low). As a result, the discharge
transistor is driven to saturation (as it is connected to Q’). The
capacitor C of the timing circuit is connected at Pin 7 of the IC
555 and will discharge through the transistor. The output of
the timer at this point is low. The voltage across the capacitor
is nothing but the trigger voltage.
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10. OPERATION
• So while discharging, if the capacitor voltage becomes less
than 1/3 VCC, which is the reference voltage to trigger
comparator (comparator 2), the output of the comparator 2
will become high. This will SET the flip-flop and hence the
output of the timer at pin 3 goes to HIGH.
• This high output will turn OFF the transistor. As a result, the
capacitor C starts charging through the resistors R1 and R2.
Now, the capacitor voltage is same as the threshold voltage
(as pin 6 is connected to the capacitor resistor junction).
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11. OPERATION
• While charging, the capacitor voltage increases exponentially
towards VCC and the moment it crosses 2/3 VCC, which is the
reference voltage to threshold comparator (comparator 1), its
output becomes high.
• As a result, the flip-flop is RESET. The output of the timer falls
to LOW. This low output will once again turn on the transistor
which provides a discharge path to the capacitor. Hence the
capacitor C will discharge through the resistor R2. And hence
the cycle continues.
• Thus, when the capacitor is charging, the voltage across the
capacitor rises exponentially and the output voltage at pin 3 is
high. 11
12. OPERATION
• Similarly, when the capacitor is discharging, the voltage across
the capacitor falls exponentially and the output voltage at pin
3 is low.
• The shape of the output waveform is a train of rectangular
pulses. The waveforms of capacitor voltage and the output in
the astable mode are shown below.
• While charging, the capacitor charges through the resistors R1
and R2. Therefore the charging time constant is (R1 + R2) C as
the total resistance in the charging path is (R1 + R2). While
discharging, the capacitor discharges through the resistor R2
only. Hence the discharge time constant is R2C.
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13. APPLICATIONS
• Astable multi-vibrators are used in amateur radio equipment
to receive and transmit radio signals.
• Astable multi-vibrators are also used in morse code
generators, timers, and systems that require a square wave,
including television broadcasts and analog circuits.
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ADVANTAGES
• Astable multi-vibrators continuously switch between one
state and another. This allows astable multi-vibrators to power
themselves and perform work at a consistent rate without
influence from any outside forces or events.
• Additionally, astable multi-vibrators are inexpensive to
produce, are relatively simple in design, and can remain
functional for extraordinary amounts of time.
14. DISADVANTAGES
• Astable multi-vibrators do not transfer the entire output
signal to the input.
• This is due to resistance within the circuit, lack of a completely
closed loop at the output terminals, and the tendency for one
capacitor or transistor to absorb energy at a slightly different
rate than the other.
• Although the amplifier restores the lost energy when it
amplifies the signal, the signal will eventually be too small to
be of any use.
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15. DECADE COUNTER IC CD4017
• 4017 IC is a CMOS decade counter chip. It can produce output
at the 10 pins (Q0 – Q9) sequentially, means it produce output
one by one at the 10 output pins.
• This output is controlled through the clock pulse at PIN 14. At
first, output at Q0 (PIN 3) is HIGH, then with each clock pulse,
output advance to the next PIN.
• Like one clock pulse makes the Q0 LOW and Q1 HIGH, and
then the next clock pulse makes the Q1 LOW and Q2 HIGH,
and so on.
• After the Q9, it will start from the Q0 again. So it creates
sequential ON and OFF of all the 10 OUTPUT PINs 15
19. WORKING OF CIRCUIT
• In this digital dice circuit we have used 6 LEDs, each LED
represent a number (1-6) of Dice.
• LEDs start flashing as we press the Push button and stops
when we release it.
• After release, illuminated LED tells the numbers, you got on
Dice.
• Like if fifth number LED remains ON after releasing the
button, means you got 5 on Dice.
• We have connected 6 LEDs to the output Q0 to Q5, and the
seventh output Q6 is connected back to the RESET PIN 15.
• So that after LED 6 it starts from the First LED at Q0. 19
20. WORKING OF CIRCUIT
• To apply the clock pulse at PIN 14 of 4017 IC, we have used
555 timer IC in Astable mode.
• The oscillated output generated at PIN 3 of 555 has been
applied to the PIN 14 of 4017, so that output can be advanced
with each clock pulse.
• We can control the speed of flashing LEDs by using the
potentiometer (RV1), rotating the potentiometer knob will
change oscillation frequency of 555 timer, hence the rate of
clock pulse.
• The frequency of the 555 can be calculated using this
formula:
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21. WORKING OF CIRCUIT
• In this digital dice circuit we have kept the oscillation
frequency so high that no one can cheat.
• LED flashing speed is directly proportional to oscillation
frequency of 555, as High the frequency, as high the speed of
flashing.
• You can increase frequency according to you, by rotating the
potentiometer.
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