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LM317 AS A BATTERY CHARGER

Summer Internship Project Report

Submitted in partial fulfillment of the requirements for the degree of

Bachelor of Technology (B.Tech)

By

July 2010

 

SHRI BALWANT INSTITUTE OF TECHNOLOGYApproved by AICTE, Min of HRD, Govt of India & DTE, Govt of Haryana

Affiliated to MD University, RohtakMeerut Road (Pallri), Near DPS, Sonepat-131001, Haryana

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CERTIFICATE 

This is to certify that the Project titled LM317 AS A BATTERY CHARGER and

submitted by Divya chawla having Roll No ECE/08/113 for the partial fulfillment of

the requirements for the degree of Bachelor of Technology/Engineering (B.Tech/

B.E.), embodies the bonafide work done by her under my supervision.

 

 

__________________________

Signature of the Supervisor

Place: New Delhi

Date: ____________________

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Acknowledgement

This report gives the details of the project work done at the end of IV

semester during the summer vacation for partial fulfillment of the

requirements for the degree of Bachelor of Technology/Engineering

(B.Tech/ B.E.), under the Supervision of.

I am very grateful to my supervisor Sanjay Nakhasi his help and able

guidance for the project. I am very thankful to my Institute, for

providing me resources and facilities to help in the project.

____________________ Signature of the Student

Name: ______________

Date: ______________

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Table of Contents

1 Introduction..................................................................................................................5

2 feasibility report...........................................................................................................6

3 Requirement Specification...........................................................................................7

4 Design Specification....................................................................................................8

5 Conclusion...................................................................................................................9

6 Checklist....................................................................................................................11

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1 Introduction

We are delighted to hereby present our project report that was undertaken during June 2010, microtek india pvt. ltd, where aims at giving training to student for advancement in power supplys.

The project undertaken was “LM317 as a Battery Charger”

In the project to follow, we should emphasis the kind the quality and standards being maintained at industries. It would include the main objectives and project details. Stress is also laid on main features of LM317.

And finally a word of thanks to microtek staff which had been painstaking helping us to complete this project.

Company profile

MICROTEK - A MASTER IN ITS CHOSEN FIELD

MICROTEK INTERNATIONAL PVT. LTD., is the country's Largest Power Products manufacturer

having products like Line Interactive UPS, ONLINE UPS, DIGITAL & SINEWAVE INVERTERS/

EXPORTED WORLDWIDE

MICROTEK products have received worldwide acceptance because of its quality & reliability and are exported to many countries. No wonder the products carry many quality approvals.

OUR PRODUCTS

Microtek has Complete Range of Digital and Sinewave Inverters, UPS EB and UPS E²from 400VA to 1550VA, which are designed and developed using world's latest technologies by Microtek's highly professional and experienced in-house R&D team, in technical association with Motorola approved design house in Taiwan and

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Microchip, USA. Constant & Continuous Regulated Charging technique / Intellicharge Pulse Technology and Dura Retain Technology are the main technologies pioneered in Microtek Inverters /UPS EB/UPS E².

Microtek Hi-End Range of Sinewave Inverters from 2KVA to 20KVA, includes models 5.5KVA, 8KVA, 10KVA and 20KVA, specially designed for providing backups to even air-onditioners. These inverters provide pure sinewave form, which is absolutely safe for the appliances connected. The applications include BACKUP for, Airconditioners, Washing Machines, Water Motor, LCD TV, Petrol Pumps, small offices, shopping malls etc.

Microtek has Line Interactive UPS models range from 600VA to 1000VA. It also has External Battery models, which have been specially designed for various backup time and multi PC requirements of customers.

Microtek has World class Range of ONLINE UPS from 1KVA to 30KVA.

Digital Inverters Sine Wave Inverters

UPS EB / UPS E²

High-End Inverters

Range of Line Interactive UPS

External Battery Line Interactive UPS

Digital Online UPS from 1KVA to 30KVA.

Inverter UPS Specialist Batteries

Sealed Maintenance Free (VRLA) Batteries

About the department in which we worked

.

R&D Department

A WORLD CLASS R&D TEAMMICROTEK has In-House R&D, managed by highly motivated, professionally qualified and experienced world class team of professionals, headed by IITians, and is strongly dedicated to provide technologically advanced and high quality products. Microtek's R&D is fully equipped with State-Of-The-Art World Class sophisticated testing equipments. The R&D is continuously working on products development as per changing products usage criteria and for users benefit by making the products more and more efficient.

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3. Requirement Specification

LM317 : LM317 is the standard part number for an integrated three-terminal

adjustable linear voltage regulator. LM317 is a positive voltage regulator supporting

input voltage of 3V to 40V and output voltage between 1.25V and 37V. A typical current

rating is 1.5A although several lower and higher current models are available. Variable

output voltage is achieved by using a potentiometer or a variable voltage from another

source to apply a control voltage to the control terminal. LM317 also has a built-

in current limiter to prevent the output current from exceeding the rated current, and

LM317 will automatically reduce its output current if an overheat condition occurs under

load. LM317 is manufactured by many companies, including National

Semiconductor, Fairchild Semiconductor, and STMicroelectronics.

Although LM317 is an adjustable regulator, it is sometimes preferred for high-precision

fixed voltage applications instead of the similar LM78xx devices because the LM317 is

designed with superior output tolerances. For a fixed voltage application, the control pin

will typically be biased with a fixed resistor network, a Zener diode network, or a fixed

control voltage from another source. Manufacturer datasheets provide standard

configurations for achieving various design applications, including constant current

sources and the use of a pass transistor to achieve regulated output currents in excess of

what the LM317 alone can provide.

LM317 is available in a wide range of package forms for different applications including heatsink mounting and surface-mount applications. Common form factors for high-current applications include TO-220 with part number LM317T and TO-3 with part number LM317K. LM317 is capable of dissipating a large amount of heat at medium to high current loads and the use of a heatsink is recommended to maximize the lifespan and power-handling capability

DIODE:  electronics, a diode is a two-terminal electronic component that

conducts electric current in only one direction. The term usually refers to

a semiconductor diode, the most common type today. This is a crystalline piece

of semiconductor material connected to two electrical terminals.[1] A vacuum tube

diode (now little used except in some high-power technologies) is a vacuum tube with

twoelectrodes; a plate and a cathode.

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The most common function of a diode is to allow an electric current to pass in one

direction (called the diode's forward direction) while blocking current in the opposite

direction (the reverse direction). Thus, the diode can be thought of as an electronic

version of a check valve. This unidirectional behavior is called rectification, and is used

to convert alternating current to direct current, and to extract modulation from radio

signals in radio receivers.

However, diodes can have more complicated behavior than this simple on-off action, due

to their complex non-linear electrical characteristics, which can be tailored by varying the

construction of theirP-N junction. These are exploited in special purpose diodes that

perform many different functions. For example, specialized diodes are used to regulate

voltage (Zener diodes), to electronically tune radio and TV receivers (varactor diodes), to

generate radio frequency oscillations (tunnel diodes), and to produce light (light emitting

diodes).

Diodes were the first semiconductor electronic devices. The discovery of

crystals' rectifying abilities was made by German physicist Ferdinand Braun in 1874. The

first semiconductor diodes, called cat's whisker diodes were made of crystals of minerals

such as galena. Today most diodes are made ofsilicon, but other semiconductors such

as germanium are sometimes used

PCB: A printed circuit board, or PCB, is used to mechanically support and electrically

connectelectronic components using conductive pathways, tracks or signal

traces etched from copper sheets laminated onto a non-conductive substrate. It is also

referred to as printed wiring board (PWB) or etched wiring board. A PCB populated with

electronic components is a printed circuit assembly (PCA), also known as a printed

circuit board assembly (PCBA).

PCBs are inexpensive, and can be highly reliable. They require much more layout effort and higher initial cost than either wire-wrapped or point-to-point constructed circuits, but are much cheaper and faster for high-volume production. Much of the electronics industry's PCB design, assembly, and quality control needs are set by standards that are published by theIPC organization

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4. Design specification

S.no Product Quantity

1. Lm317 1

2. 0 pcb(printed circuit board) 1

3. Electrolytic capacitor 1

4. Resistances(0.2k,240,2.4k) 3

5. Transformer.(18V 5A) 1

6. Soldering iron(25 w) 1

7. Variable resistance 1

8. Diode.(IN007) 4

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About LM317

LM317 is the standard part number for an integrated three-terminal

adjustable linear voltage regulator. LM317 is a positive voltage

regulator supporting input voltage of 3V to 40V and output voltage between

1.25V and 37V. A typical current rating is 1.5A although several lower and higher

current models are available. Variable output voltage is achieved by using

a potentiometer or a variable voltage from another source to apply a control

voltage to the control terminal. LM317 also has a built-in current limiter to prevent

the output current from exceeding the rated current, and LM317 will automatically

reduce its output current if an overheat condition occurs under load. LM317 is

manufactured by many companies, including National Semiconductor, Fairchild

Semiconductor, and STMicroelectronics.

Although LM317 is an adjustable regulator, it is sometimes preferred for high-

precision fixed voltage applications instead of the similar LM78xx devices

because the LM317 is designed with superior output tolerances. For a fixed

voltage application, the control pin will typically be biased with a fixed resistor

network, a Zener diode network, or a fixed control voltage from another source.

Manufacturer datasheets provide standard configurations for achieving various

design applications, including constant current sources and the use of a

pass transistor to achieve regulated output currents in excess of what the LM317

alone can provide.

LM317 is available in a wide range of package forms for different applications

including heatsink mounting and surface-mount applications. Common form

factors for high-current applications include TO-220 with part number LM317T

and TO-3 with part number LM317K. LM317 is capable of dissipating a large

amount of heat at medium to high current loads and the use of a heatsink is

recommended to maximize the lifespan and power-handling capability.

LM337 is the negative voltage complement to LM317 and the specifications and

function are essentially identical, except that the regulator must receive a control

voltage and act on an input voltage that are below the ground reference

point instead of above it.

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Specifications

Vout range 1.25V - 37V

Vin - Vout difference 3V - 40V

Operation ambient temperature 0 - 125°C

Output Imax <1.5A

Minimum Load Currentmax 10mA

LM317 as a voltage regulator

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The current limiting characterstics of lm317

CIRCUIT DESIGN

The main circuit design of the 12 v battery charger using LM317 is presented here.this circuit is used to charge a 12v battery when the Vin pin of lm317 is given a D.C.supply of 20 v.

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This circuit can be made to work on A.C. by attaching components like transformer .a bridge wave rectifier and capacitor for the filtering action to work on 230v a.c. The LM317 is a monolitic integrated circuit. It's a 3 terminal positive voltage.

The LM317 is a monolitic integrated circuit. It's a 3 terminal positive voltage regulator designed to supply more than 1.5A of load current with an output voltage adjustable over a 1.2 to 37V. It employs internal current liniting, thermal shut-down and safe area compensation. The LM317 is cheap,

able.This circuit is simply constructed by first mounting the components on a 0 pcb and then it is simply soldered weth the help of a soldering iron and a soldering wire.in this circuit the diffrence between the Vin and Vout cannnot be more than 40.Thats why this circuit is used for charging.There are two important things to keep in mind when working with an LM317T:

    First, the internal circuitry of the LM317T can only handle 1.5 A of current as an absolute maximum.

    Secondly, and this is important, the LM317T is a linear regulator. This means that it dissipates the excess voltage as heat, with more heat produced as the voltage is set lower and lower. You MUST have a heatsink mounted on the regulator that is capable of dissipating the heat produced.

The circuit takes its input from transformer connected to bridge wave rectifier and capacitor which performs the filtering action after that it is connected to Vin .Bridge rectifier converts A.C. into D.C. and the capacitor performs the filtering action.which aftrwards supply it into the circuit.its output is taken across R1 & R2 where it is connected to the terminals of battery for charging.

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4. Conclusion

Here we have used lm317 as a battery charger.a very simple circuit is used for illustrating the use of lm317 in charging circuits.

Here LM317 battery charger is used to charge the battery of 12 v.

To make it work on ac we have attached a capacitor and a rectifier using 4 diodes bridge wave rectifier for supplying the ac voltage of 230 volts directly.

Therefore LM317 can be use to charge the circuits by its voltage regulating property.it can work on A.C and D.C. both provided in case of A.C. some additional components are added .

In simple words it is a very cheap and easy circuit for charging batteries upto 12v.

Hence the project is completed and pcb is working properly

Apart from project I have gone through other circuits .and various circuit elemnts like relays,diffrences between online and offline UPS,IC55 timer,PCBs of stablizers ,UPS etc.which are not the part of project.But would be very valuable for me in the future.

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2 ChecklistThis checklist is to be attached as the last page of the report.

 

This checklist is to be duly completed by the student and verified by the Supervisor, Project Coordinator and HOD

  

1.          Is the report properly hard bound? Yes / No

2.          Is the Cover page (on hard bound cover) in proper format? Yes / No

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3.          Is the Title page (Inner cover page) in proper format? Yes / No

4.          (a) Is the Certificate from the Supervisor in proper format?

(b) Has it been signed by the Supervisor?

Yes / No

Yes / No

5.          (a) Is the Acknowledgement from the Student in proper format?

(b) Has it been signed by the Student?

Yes / No

7.          Does the Table of Contents include page numbers?

(i).           Are the Pages numbered properly?

(ii).         Are the Figures numbered properly?

(iii).        Are the Tables numbered properly?

(iv).       Are the Captions for the Figures and Tables proper?

(v).        Are the Appendices numbered properly?

Yes / No

Yes / No

Yes / No

Yes / No

Yes / No

Yes / No

8.          Is the conclusion of the Report based on discussion of the work? Yes / No

9.          Are References or Bibliography given in the Report?

Have the References been cited inside the text of the Report?

Is the citation of References in proper format?

Yes / No

Yes / No

Yes / No

10.      A Compact Disk (CD) containing the softcopy of the Final Report (preferably in PDF format) and a Final Project Presentation in MS power point only (made to the Supervisor / Examiner has been placed in a protective jacket securely fastened to the inner back cover of the Final Report. Write the name and Roll No on the CD.

Yes / No

 

Declaration by Student

I certify that I have properly verified all the items in the checklist and ensure that the report is in proper format as specified in the course handout.

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Name:

Place:

Date:

Signature of the Student:

Verification by Supervisor

I have duly verified all the items in the checklist and ensured that the report is in proper format.

 

Name:

Place:

Date:

Signature of the Supervisor: