ELECTRONIC &COMMUNICATION SEM-3 YEAR-2014/15 ELECTRONIC DEVICES AND CIRCUITS ( ) ACTIVE LEARING ASSIGNMENT

Pooja Patel ( ) Varsha Shukla ( ) Akshay Parekh ( ) Rohit sutariya ( ) Brinda Gandhi ( ) GUIDED BY :- PROF. KRUPA PATEL VENUS INTERNATIONAL COLLAGE OF TECHNOLOGY PREPARED BY :-

Presentation Outlines 1. Introduction 2. types 3. working 4. Application 5. Advantages 6. Disadvantages 7. bibliography

 INTRODUCTION OF TRANSISTOR It is a three terminal semiconductor device having two junctions. It is bipolar junction transistor having two type N-P-N & P-N-P. Three terminal are (1) emitter (2) base (3) collector. To operate transistor as an amplifier connected in active region, The emitter-base junction is forward bias & collector-base junction is reverse bias.

 INTRODUCTION

A transistor is a semiconductor device commonly used to amplify or switch electronic signals. A transistor is made of a solid piece of a semiconductor material, with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current flowing through another pair of terminals.

 Types of TRANSISTOR Heterojunction bipolar transistor Alloy junction transistor Unijunction transistors Pentode transistor Darlington transistors Photo transistor Inverted-t field effect transistor Avalanche transistor Thin film transistor

 HOW A TRANSISTOR WORKS A transistor can control its output in proportion to the input signal; this is called an "amplifier". Or, the transistor can be used to turn current on or off in a circuit like an electrically controlled "switch", where the amount of current is determined by other circuit elements.

 TRANSISTOR HAS A SWITCH The basic component used in implementing any digital logic circuit is a switch.modern digital ic’s use a high speed transistor switches used in implementing digital ics bjt and mosfet. The primary function of a transister switch in a digital logic circuit is to alternately connect and disconnect a load to and from circuit power supply.in doing this the transistor switch produces two distinct voltage levels across the load which represents the binary o and binary 1

 TRANSISTOR HAS A SWITCH In 1 state the transistor is non-conducting or cut-off and acts as essentially an open circuit.in the other state i.e.on 0 state the transistor is conducting heavily and acts as a very low resistance approaching to a short circuit. The two state logic input signal is applied to the transistor to produce this on-off operation. Now there are two types of ics; -saturated ic -non-saturated ic

 TRANSISTOR HAS A SWITCH The cut-off and linear regions are found in the non- saturated bipolar circuits whereas cut-off satyration modes are found in saturated bipolar circuits. In non-saturating digital circuits the transistor switches between cut-off and linear region.they are also used in many application where high speed opration is desirable. In case of the saturated bipolar transistor too,cut-off and saturation states are found.most digital circuitry in use today use saturated bipolar switching transistor for data representation.

 APPLICATION The transistor as an amplifier. The transistor as switch. Integrated Circuits.

 ADVANTEGES 1. Transistors are small. 2. require very little power. 3. run cool. 4. much more reliable. 5. Because of the transistors the 2nd generation computers were small, faster and reliable.

 DISADVANTEGES Costly. had less memory than ICs. Require much space than ICs.

 Bibliography 1. www. whereisdoc. com 2. www. slideshare. net 3. www. eforu. com 4. Microsoft power point