Digital IC Tester Using AT89S52 Microcontroller (For 74TTL Series Digital ICs)

ABSTRACT

This digital Integrated Circuit tester (IC tester) is used to test Integrated Circuits (ICs). We can easily test any digital IC using this kind of an IC tester. For testing an IC, we need to use different hardware circuits for different ICs; like we need a particular kind of tester for testing a logic gate and another for testing flip flops or shift registers which involves more complication and time involved will also be more. So here’s an IC tester to overcome this problem. Unlike other IC testers, this is more reliable and easier since we don’t need to rig up different kind of circuits for different kind of ICs, each time we need to test them.

This IC tester is constructed using 89c55 microcontroller along with a keyboard and a display unit. It can test digital ICs having a maximum of 24 pins. Since it is programmable, any number of ICs can be tested within the constraint of the memory available. This is a project based on arm7 microcontroller, which test the 74xx series IC. The coding includes testing of 7400, 7402, 7404, 7408, 7432, 7486 IC. It can be extended further Based on the need.

CHAPTER ONE

1.1                                                        INTRODUCTION

The digital IC tester is implemented by using the 8051 (AT89S52) microcontroller. The processing of the inputs and outputs is done by the microcontroller. The display part on the microcontroller board is modelled using LCD. After the successful testing of the IC, the result is displayed on the LCD.

The basic function of the digital IC tester is to test a digital IC for correct logical functioning as described in the truth table and/or function table. It can test digital ICs having a maximum of 14 or 16 pins. Since it is programmable, any number of ICs can be tested within the constraint of the memory available. This model applies the necessary signals to the inputs of the IC, monitoring the outputs at each stage and comparing them with the outputs in the truth table. Any discrepancy in the functioning of the IC results in a fail indication, displays the faulty and good gates on the LCD. The testing procedure is accomplished with the help of keys present on the main board.

This is a project based on arm7 microcontroller, which test the 74xx series IC. The coding includes testing of 7400, 7402, 7404, 7408, 7432, 7486 IC. It can be extended further Based on the need.

This includes an extra board which have IC holder and which holds the IC’s which are to be tested. And this board also includes some push button which tells the system which IC is being tested. U just have to put in the ic and press the relative button to test the ic.

1.2                                             OBJECTIVE OF THE PROJECT

The objective of this work is to design a digital ic tester used in testing  digital IC’s, mainly belonging to the 74TTL series. FLIP-FLOP IC‟s (7400, 7402, 7404, 7408, 7432, 7474, 7486).

1.3                                         SIGNIFICANCE OF THE PROJECT

Unlike the IC testers available in the market today which are usually expensive, this IC tester is affordable and user-friendly. This IC tester is constructed using 8951 microcontroller along with a display unit. It can test digital ICs having a maximum of 24 pins. Since it is programmable, any number of ICs can be tested within the constraint of the memory available. This IC tester can be used to test a wide variety of ICs which includes simple logic gates and also sequential and combinational ICs like flip-flops, counters, shift registers etc. It is portable and easy to use.

1.4                                                 SCOPE OF THE PROJECT

An Integrated Circuit tester (IC tester) is used to test Integrated Circuits (ICs). We can easily test any digital IC using this kind of an IC tester. For testing an IC, we need to use different hardware circuits for different ICs; like we need a particular kind of tester for testing flip flops which involves more complication and time involved will also be more. So here’s an IC tester to overcome this problem. Unlike other IC testers, this is more reliable and easier since we don’t need to rig up different kind of circuits for different kind of ICs, each time we need to test them.

1.5                                           LIMITATION OF THE PROJECT

This is a project based on arm7 microcontroller, which is limited in testing the 74xx series IC such as 7400, 7402, 7404, 7408, 7432, 7486 IC. It can be extended further Based on the need.

1.6                                              PURPOSE OF THE PROJECT

This device is used testing of the IC, the result is displayed on the LCD. The basic function of the digital IC tester is to test a digital IC for correct logical. This device is used in testing  digital IC’s, mainly belonging to the 74TTL series. FLIP-FLOP IC‟s (7400, 7402, 7404, 7408, 7432, 7474, 7486).

1.7                                                PROBLEM OF THE WORK

1. Circuiting on breadboard was not firm enough.
2. With the help of internal clock, it was hard to synchronize the ICs which require clock so we created manual clock.

1.8                                   FUTURE EXTENSIONS OF THE PROJECT

The project can be extended as following:

1) It Can be extended for more than 16 pin ic’s by changing some hardware and coding.

2) It Can be extended to analog IC’s

1.9                                        PROJECT WORK ORGANIZATION

The various stages involved in the development of this project have been properly put into five chapters to enhance comprehensive and concise reading. In this project thesis, the project is organized sequentially as follows:

Chapter one of this work is on the introduction to a digital tester. In this chapter, the background, significance, objective limitation and problem of a digital tester were discussed.

Chapter two is on literature review of a digital tester. In this chapter, all the literature pertaining to this work was reviewed.

Chapter three is on design methodology. In this chapter all the method involved during the design and construction were discussed.

Chapter four is on testing analysis. All testing that result accurate functionality was analyzed.

Chapter five is on conclusion, recommendation and references.