This document describes a circuit that uses IC 7490 and IC 7447 to convert binary coded decimal (BCD) to a 7-segment display. IC 7490 is a decade counter that generates a 4-bit BCD code when a clock pulse is applied. This BCD code is input to IC 7447, which drives the pins of a 7-segment LED display to display the corresponding number. The circuit diagram shows how the ICs are connected along with a push button and 7-segment display. When the button is pressed it provides the clock input, causing the decade counter to increment and display the numbers 0-9 in sequence on the 7-segment display.

1. BCD to 7-segment display using IC 7490 and IC 7447
Gujarat Technological University
Prepared By:
Sanchela Maulik M. :- 14EC038
Bhatt Abhay N. :- 14EC022
B. E. (E. & C.)3rd Sem.
BHGCET, Rajkot
Internal Guide:
Prof. Manish P. Patel
Assistant Professor
E & C Dept.
BHGCET, Rajkot
Presentation of Active Learning Assignment
1

2. Outline:
 Introduction
 Component List
 Pin Diagrams and Descriptions
 Circuit Diagram and Description
 Practical circuit
 References
2

3. Introduction:
 In our project, using IC7447 and IC7490
we can convert the BCD to 7 segment.
 This project is used in displays, entry
counters, etc.
 When we apply 1 clock pulse at that time
IC7490 generates 4bit BCD code, and it’s
given to IC7447, and finally its displays in
& 7-segment display.

4. Component list:
 7 segment driver IC 7447
 Decade counter IC 7490
 7 segment led display common anode
 Resistor 330 Ω

5. 0 to 9 Binary Input Sequence
Code:

6. Pin Diagrams & Description:

7. Pin Diagram of IC 7490:

8. Pin Description of IC7490:
Pin No Function Name
1 Clock input 2 Input2
2 Reset1 R(0)1
3 Reset2 R(0)2
4 Not connected NC
5 Supply voltage; 5V (4.75V – 5.25V) Vcc
6 Reset3 R(9)3
7 Reset4 R(9)4
8 Output 3, BCD Output bit 2
QC
9
Output 2, BCD Output bit 1
QB
10 Ground (0V) Ground
11 Output 4, BCD Output bit 3
QD
12 Output 1, BCD Output bit 0
QA
13 Not connected NC
14 Clock input 1 Input1

9. Pin Diagram of IC 7447:

10. Pin Description of Ic7447:
Pin No Function Name
1 BCD Input 2 B
2 BCD Input 3 C
3 Display test; Active low LT
4 Ripple blanking output; Active low RBO
5 Ripple blanking input; Active low RBI
6 BCD Input 4 D
7 BCD Input 1 A
8 Ground (0V) Ground
9
Segment outputs; Active low
e
10 d
11 c
12 b
13 a
14 g
15 f
16 Supply voltage; 5V (4.75V – 5.25V) Vcc

11. Pin Diagram of 7- segment
common anode display:

12. Types of 7-segment Display:

13. Connection of 7447 with 7-
segment:

14. Pin Description of 7- segment
Display:

15. Function of 7 segment:

16. Circuit Diagram:

17. Circuit Diagram Description:
 Pins R0(1), R0(2), R9(1), R9(2) connected to
ground.
 Pins Q0, Q1, Q2, Q3 connected to the output
logic indicator pins of input IC7447 at A, B, C,
D.
 Clk B pin connected to Q0.
 Clk A pin connected to push button for the
input signal ground.
 Output pins of IC7447 Qa, Qb, Qc, Qd, Qe,
Qf, Qg connected to the 7- Segment Display.
 Apply 5 v Vcc Supply to the 7- Segment

18. Practical Circuit:

19. References:
 www.davidswinscoe.com/electronics/c
omponents
 www.engineersgarage.com
 www.electroschmetics.com
 www.mouser.in/embedded-solutions/
 www.electronics-tutorials.ws/

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