Digital object counter (group 12)

The Digital Object Counter using LDR (Light Dependent Resistor) is a simple system that can be made into use for counting objects in the product manufacturing area of an industry, etc. Two IC555 are used in Monostable and Astable mode for respective pulse generation.

1. Digital Object Counter Team Members ( Group 12 ): 1. Aviral Srivastava (20BCE11027) 2. Anant Kumar (20BCE11035) 3. Athuldev Kp (20BCE11050) 4. Raghuveer Singh Chouhan (20BCE11055) 5. Krutarth Dubey (20BCE11056) 6. Vivek Singh Chuphal (20BCE11069)

2. Objective of the Project The objective of our project is to build a working model of a digital object counter . To  Count  the  objects  passing through the predefine path

3. What is a Digital Object Counter? A counter machine is an abstract machine used in formal logic and theoretical computer science to model computation.  In more understandable way, it is a device which calculates the number of objects fed to its sensor and displays accordingly.  With the knowledge of IC’s (series 74), Light Dependent Resistor (LDR) and other electrical components we have created and build a digital object counter machine. The main idea on which the circuit works is the detection of absence of light by the Light Dependent Resistor and displaying the output .

4. Circuit Diagram:

5. Components used with specifications 1) IC 7490 Decade counter.  2) IC 7447.  3) IC 555 Timer. - X 2  4) Common Anode 7 segment display.  5) Light Dependent Resistor (LDR). - X 1  6) Rheostat (Variable resistor) – 100k ohm  7) Resistors 8) Capacitors: 10 µF - X 2, 0.01 µF - X 1  9) Light Emitting Diodes (LED) - X 2  10) 6V Battery for power supply  11) Connecting Wires  12) Bread boards - X 2

6. Working Principle of the Project Digital Object Counter machine mainly has four units: 1. Primary sensing unit - L.D.R 2. Counting unit - Decade counter IC 7490 3. Binary to 7-segment display conversion unit - IC 7447 4. Display unit - common anode seven segment display.

7. Advantages of the Digital Object Counter Circuit Very Low Power Consumption Wide Supply Voltage Range  Good Noise Immunity

8. Drawbacks of the Digital Object Counter Circuit Loose connections while fabricating on the bread boards  Problem with supplying the required voltage to seven segment display

9. Measures to overcome the drawbacks It’s better to use a PCB rather than a bread board  It’s better to use a voltage regulator as supply rather than a dc supply battery

10. Applications of the Project Digital Clocks Digital Cameras Money Counting Machines Walk through metal detectors X ray baggage scanners

11. 1. IC 7490 It is used as divide by 6 counter by supplying pulse at input 1 and grounding reset pins R3 and R4 and connecting QA with input 2.  7490 IC  can work like bi –quinary counter, which is used to store decimal digits in the form of 4 bit binary numbers.

12. 2.  IC 7477 That is the purpose of 7447 driver IC. It takes BCD inputs and generates the 7 output lines for the 7 segment LED. The 74xx47 chip is used to drive 7 segment display. You must use the 74xx47 with a  common anode 7-segment display  (e.g. Kingbright part number SA03). The input to the 74xx47 is a binary number  DCBA  where D is 8s, C is 4s, B is 2s and A is 1s. The inputs DCBA often come from a binary counter.

13. 3. IC 555 Timer The standard  555 timer  IC is  used  in a variety of  timer , pulse generation and oscillator applications. It can be  used  to provide time delays, as oscillators and as flip-flop elements. The  555 timer  IC is an integral part of electronics projects.

14. Seven Segement Display A  seven - segment display  is a form of electronic  display  device for  displaying  decimal numerals that is an alternative to the more complex dot matrix  displays .  Seven - segment displays  are widely used in digital clocks, electronic meters, basic calculators, and other electronic devices that  display  numerical information

15. 5. 100k Variable Resistor This  100k  ohm Trimpot is a type of  variable resistor  in a metal packaging, It can be easily mounted on PCB and adjusted using screw driver. Specifications:- Model Type : Metal Preset.  Resistance  Value :  100k  ohm.  Resistance  Tolerance : 5%

16. 6. LDR Photo resistors, also known as light dependent resistors ( LDR ), are light sensitive devices most often used to indicate the presence or absence of light, or to measure the light intensity. LDRs have a sensitivity that varies with the wavelength of the light applied and are nonlinear devices.

17. References for the Project http://www.buildcircuit.com/digital-object-counter/ http://en.wikipedia.org/wiki/Counter_machine http://www.buildcircuit.com/ldr-engineer/ http://www.articlesnatch.com/Article/A-Short-History-Of-The-Currency-Counting- Machine/8179440

18. Screenshot of the Circuit: