![International Journal of Trend in Scientific Research and Development (IJTSRD)
Volume 4 Issue 5, August 2020 Available Online: www.ijtsrd.com e-ISSN: 2456 – 6470
@ IJTSRD | Unique Paper ID – IJTSRD31834 | Volume – 4 | Issue – 5 | July-August 2020 Page 364
Mini CNC Plotter and Laser Engraver
Aishwarya Gunjal, Ashwini Deshmukh, Priyal Narkar, Prof. Ameya Jadhav
Department of Electronics Engineering, Atharva College of Engineering, Mumbai, Maharashtra, India
ABSTRACT
CNC Machine system hasbeen already implemented in industriesbutatavery
greater cost. Now-a-days because of growing technology in various
dimensions. CNC system will make it easier for humans. Our idea of
implementing MiniCNC Plotter and Laser Engraver isintroducestoreducethe
man power. This paper discuss the design and implementation of two
dimensional CNC router. Mini CNC plotter is designed to create complex
designs as well as easy designs by just simple software. We have used CD
drives and along with that stepper motors which gives proper provision of
axes. This project has Arduino as its brain, through which inputs are given.
KEYWORDS: Arduino, CNC, CD drives
How to cite this paper: Aishwarya Gunjal
| Ashwini Deshmukh | Priyal Narkar |
Prof. Ameya Jadhav"Mini CNC Plotterand
Laser Engraver" Published in
International Journal
of Trend in Scientific
Research and
Development(ijtsrd),
ISSN: 2456-6470,
Volume-4 | Issue-5,
August 2020, pp.364-
366, URL:
www.ijtsrd.com/papers/ijtsrd31834.pdf
Copyright © 2020 by author(s) and
International Journal of TrendinScientific
Research and Development Journal. This
is an Open Access article distributed
under the terms of
the Creative
Commons Attribution
License (CC BY 4.0)
(http://creativecommons.org/licenses/by
/4.0)
I. INTRODUCTION
Computer Numerical Control is used in industries to reduce
man power and make work efficient and easy. In CNC
machine system machine tools are functioning by a
numericalcontrol. In this system, machinesareprogrammed
by CNC machine language called as G-Codes. G-Codes
controls the speed of the process, efficiency rate,
coordination of the axes. Both metaland plastic partscanbe
used to implement this structure. Our idea isinspiredbyCNC
plotter machine whichis used for the job ofcreatingcomplex
designs. Our idea of this project is to create complex images
by high watt burning laser machine module. This can be
done on any surface. Wooden surface, plastic surface or
metal surface. The two stepper motors and one servo motor
used, helps in movements of X, Y axes. Two CD Drives are
used for the movement on axes. Microcontroller is used to
controls the proper synchronization of these three motors
during the process. The motors winding voltages were
displayed on the oscilloscope during the printing process to
investigate the synchronization between the three motors.
Arduino bases software language is used to operate this
machine. Inputs are given though Arduino. The design ofthe
circuit issimple, inexpensive and can beaccomplishedusing
commercially available components. This machine will be
implemented in a miniature structure. To keep it low space
occupied and light weight we will use wooden or aluminum
parts to implement this structure of project[3]
II. RELATED WORK
From this module we describe the design and structure of
small two dimensional CNC router, monitoring system and
controlling system. Previous systemsusedthreedimensional
CNC machines to implement their structures. In old papers
CNC machine systems was suitable for designing metallic
and non-metallic materials. Using three axis. The three axes
are X, Y and Z respectively. The biggest drawback of these
systems was complexity of connections, complexity of
working of tools and small machines used, difficulty to
understand each part, costly, high weight and occupies a bit
of more space. To overcome these problems we proposedan
idea of designing two axis CNC plotter machine which is low
in weight as compared to old implemented CNC plotter
machines. It is possible because of two axis and wooden
materialwithcompactsize. It can be made more lightweight
by using aluminum parts for construction of this system. In
our system we have to convey instructions to the machines
by using software whichwill be installed in computerdevice
or laptops which contains G-Codes to operate CNC plotter
system. Inputs will be given to Arduino. Then further
operation is carried out by stepper motors and servo motor.
As per the commands laser starts to move along XandYaxes
and engrave the images on given object. And the laser
module is controlled by laser driver[5]
III. SYSTEM DESIGN
The working of CNC plotter can be explained with the
following steps.
A. Connecting and assembling.
The first step includes connecting arduinoand L293Dmotor
driver properly, connecting CD drivers, stepper motor and
servo motor driver shield. A laser or a pen is also added
which will help us in the process of engraving.
IJTSRD31834](https://image.slidesharecdn.com/66minicncplotterwithlaserengraver-1-200911054617/85/Mini-CNC-Plotter-and-Laser-Engraver-1-320.jpg)
![International Journal of Trend in Scientific Research and Development (IJTSRD) @ www.ijtsrd.com eISSN: 2456-6470
@ IJTSRD | Unique Paper ID – IJTSRD31834 | Volume – 4 | Issue – 5 | July-August 2020 Page 365
For laser engraving, the pen is replaced with the laser which
will perform engraving operations for engraving logos and
trademarks [1]
Fig.1 CNC plotter
B. Software processing and Engraving.
For the software part, we use arduino programming and
inkscape software. The arduinowill read the inputs given to
it and convert into an output that isactivatinga motor while
the inksacpe software is a graphics editor which we use to
create border and convert image or text into g code files and
hence save our g code files. We need to convert this images
and texts into codes so that our machine understands.
Whenever a code is uploaded, the arduino commands the
motors to operate. With the help of stepper drivers, the
stepper motor starts working and moving along axis. The
laser is connected with the help of a laser screw. This screw
helps in the movement of the laser along the axis X,Y or Z. In
this way, the laser will start working that is it can start
engraving by burning or evaporating the material. During
the process of laser engraving, the laser impinges on the
materialwhichcreates a greatamount of heat. This heatcan
change the colour, create a contrast depending upon the
amount of time of heat or the exposure. Hence burning or
evaporating the material [7]
IV. DESCRIPTION OF UNIT
1. Power supply:
It is a component which converts one type of electrical
energy to other like mechanical or chemical energy into
electrical energy. At least one electric load can be operated
using power supply. For example, a computer is a device
which converts AC power to several DC voltages.
2. Stepper motor:
Fig. 2 Stepper motor
A stepper motor is a synchronous, brushless motor which
divides full rotation in number of steps. An
electromechanical devicewhichconvertselectricalenergyto
mechanical energy is called stepper motor. As long as the
motor is sized to application, the position of motor can be
controlled without any feedback mechanism. Generally,
stepper motors are DC motors which have multiple coils
moving in discrete steps.
3. Servo motor:
Fig. 3 Servo motor
A servo motor is a device whichallows precise controlonthe
moments like push or rotate. It is a device which operates
through servo mechanism. By using servo motor we can
rotate an object to desired angles or distance. Servo motor,
because of these features is used in many applications like
robotics or automated manufacturing.
4. G-codes:
G-codes are used to command any computerized machine
how to perform a specific task like simple moves or
functions like drilling. EachG-code hasa group numbereach
group has commands for specific subject.
5. Ardiuno uno:
Fig. 4 Arduino Uno
It is a microcontroller based on microchip ATmega328P
microcontroller. It can be used to interface many shields
(boards) and variouscircuitsas ithas 14 digitaland6analog
input/output pins. These pins can be programmed using
Arduino IDE with USB cable. Arduino provides with the
facility of communication with computer or other arduino
board where ATmega328Pis used for serialcommunication.](https://image.slidesharecdn.com/66minicncplotterwithlaserengraver-1-200911054617/85/Mini-CNC-Plotter-and-Laser-Engraver-2-320.jpg)
![International Journal of Trend in Scientific Research and Development (IJTSRD) @ www.ijtsrd.com eISSN: 2456-6470
@ IJTSRD | Unique Paper ID – IJTSRD31834 | Volume – 4 | Issue – 5 | July-August 2020 Page 366
Features of Arduino
A. Microcontroller ATmega 328
B. Operating Voltage5V
C. Input Voltage7-9V
D. Digital I/O Pins 14(of which 6 provide PWM output)
E. Analog Input Pins 8(of which 4 are broken out onto
pins)
F. DC Current per I/OPin40mA
G. Flash Memory 32 KB (2K Bused by boot loader)
H. SRAM 2 KB
I. EEPROM 1 KB
J. Clock Speed 16 MHz
6. X-Y-Z axis stepper drivers:
These stepper drivers are used to control the movement
over X, Y and Z axis. In X direction the stepper motor will
move left and right in Y direction the stepper motor will
move front and back and in Z direction the stepper motor
will move up and down. These are easy-to-use stepper
drivers which are mounted on the arduino. By using these
drivers stepper motor current can be controlled.Thestepper
driver will rotate the lead screw which in turn will control
the movement of pen/laser.
7. Laser:
Here the laser used is Focusable Laser Module 200-250 mW
650 nm. The outer metal housingwork asa Heat sinkfor the
laser diode. It has focusable lens for the adjustment of laser
dot. The laser wire terminal is connected to the laser socket
on the driver board.
V. ADVANTAGES
For drawing blueprints on paper surface.
Creating complex designs.
Engravingcomplex designs on metalorwoodensurfaces
To replace human labor.
To increase machine work.
To increase the speed of operation
Negligible proportion of defective items.
Material efficiency – waste minimization.
Flexibility and efficiency of production.
Energy efficiency.
Ability to use shorter production cycles.
Automation and independence of the production
process.
Ease of use and manufacture of devices.
Versatility – anything in a form of picture.
Possibility of machining of a variety of materials.
Quick change in manufactured product /design.
A. Laser engraver: By replacing the pen with lasermachine
we can perform laser engraving operations for
engraving different logo, trademarks, benchmarks etc.
B. 3 Dimensional Printing: By replacing the pen with 3 D
extrusion pen, we can perform 3 D modeling which is
the fastest growing technology.
C. Laser cutter: Instead of using pen laser cutters can be
used for high precision machining operations.
D. Milling operations: Different milling operations such as
slotting, grooving etc. can be performed provided with
over arm and arbor [5].
VI. CONCLUSION
In this project, a small scale CNC Plotter with laser engraver
is designed and analyzed. The Special Application CNC
engraving machine based on Arduino is designed. The
Arduino based CNC machine has 3 axis motions which
communicates with the Arduino board which in turn drives
the stepper motor drivers which run the stepper motor. The
motor load calculationswere done on no load condition and
suitable allowance for machining is provided. This system
functioning onG-codes and Arduino asits brainispossibleto
engrave complex images and designs on any kind of surface
[1]
VII. REFERENCES
[1] Udit Pandey, Swapnil Raj Sharma, “Model and
Fabrication of CNC Plotter Machine”, International
Journal of Advanced Research in Computer and
Communication Engineering ISO 3297:2007 Certified
Vol. 6, Issue 6, June 2017.
[2] Harsh B. Panchal, Mayur S. VAJA, Priyanka D. Patel,
Uday N. Padia, “ARDUINO BASED CNC MACHINE”,
International Journal of Research In Science &
Engineering Special Issue 7-ICEMTE March 2017.
[3] Aneeta Pinhiero, Beljo Jose, Tinsemon Chacko, Nazim
TN, “Mini CNC Plotter”, INTERNATIONAL JOURNAL
OFINNOVATIVE RESEARCH IN ELECTRICAL,
ELECTRONICS, INSTRUMENTATION AND CONTROL
ENGINEERING Vol. 4, Issue 4, April 2016.
[4] Kajal J. Madekar, Kranti R. Nanaware, Pooja R.
Phadtare, Vikash S. Mane, “Automatic mini CNC
machine for PCB drawing and drilling” International
Research Journal of Engineering and Technology
(IRJET), Volume: 03; Issue: 02; Page No. 1106-1110;
2016.
[5] JamesFloyd Kelly, Patrick Hood-Daniel,Buildyourwon
CNC machine (The United States of America, Paul
Manning, 2009)
[6] Advertisement. Home Improvement Made Easy with
New Lower Prices | Improve & Repair with The Home
Depot. Web. 25 Apr. 2011. htt://www.homedepot.com.
[7] ATmega48A/48PA/88A/88PA/168A/168
PA/328/328P Datasheet, Atmel Corporation, Aug.
2010,
http://www.atmel.com/dyn/resources/prod_documen
ts/doc8271.pdf.
[8] Closed, Soldering Sj2. “Easy Driver Stepper Motor
Driver.” SchmalzHaus.com Brian SchmalzHomepage.
Web. 08 Apr. 2011.
http://www.schmalzhaus.com/EasyDri ver.
[9] CNC Machine Manufacturers. Photograph. Review
about CNC Machine. Web. 25 Apr.2011.
http://www.cncmachine-details.info/cnc-
machinemanufacturers.html.
[10] “Design Fundamentals for Phototransistor Circuits.”
Fairchild Semiconductor, 30 Apr. 2002. Web. 25Apr.
2011. https://www.fairchildsemi.com/application-
notes/AN/AN-3005.pdf.](https://image.slidesharecdn.com/66minicncplotterwithlaserengraver-1-200911054617/85/Mini-CNC-Plotter-and-Laser-Engraver-3-320.jpg)
Mini CNC Plotter and Laser Engraver
- 1. International Journal of Trend in Scientific Research and Development (IJTSRD) Volume 4 Issue 5, August 2020 Available Online: www.ijtsrd.com e-ISSN: 2456 – 6470 @ IJTSRD | Unique Paper ID – IJTSRD31834 | Volume – 4 | Issue – 5 | July-August 2020 Page 364 Mini CNC Plotter and Laser Engraver Aishwarya Gunjal, Ashwini Deshmukh, Priyal Narkar, Prof. Ameya Jadhav Department of Electronics Engineering, Atharva College of Engineering, Mumbai, Maharashtra, India ABSTRACT CNC Machine system hasbeen already implemented in industriesbutatavery greater cost. Now-a-days because of growing technology in various dimensions. CNC system will make it easier for humans. Our idea of implementing MiniCNC Plotter and Laser Engraver isintroducestoreducethe man power. This paper discuss the design and implementation of two dimensional CNC router. Mini CNC plotter is designed to create complex designs as well as easy designs by just simple software. We have used CD drives and along with that stepper motors which gives proper provision of axes. This project has Arduino as its brain, through which inputs are given. KEYWORDS: Arduino, CNC, CD drives How to cite this paper: Aishwarya Gunjal | Ashwini Deshmukh | Priyal Narkar | Prof. Ameya Jadhav"Mini CNC Plotterand Laser Engraver" Published in International Journal of Trend in Scientific Research and Development(ijtsrd), ISSN: 2456-6470, Volume-4 | Issue-5, August 2020, pp.364- 366, URL: www.ijtsrd.com/papers/ijtsrd31834.pdf Copyright © 2020 by author(s) and International Journal of TrendinScientific Research and Development Journal. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0) (http://creativecommons.org/licenses/by /4.0) I. INTRODUCTION Computer Numerical Control is used in industries to reduce man power and make work efficient and easy. In CNC machine system machine tools are functioning by a numericalcontrol. In this system, machinesareprogrammed by CNC machine language called as G-Codes. G-Codes controls the speed of the process, efficiency rate, coordination of the axes. Both metaland plastic partscanbe used to implement this structure. Our idea isinspiredbyCNC plotter machine whichis used for the job ofcreatingcomplex designs. Our idea of this project is to create complex images by high watt burning laser machine module. This can be done on any surface. Wooden surface, plastic surface or metal surface. The two stepper motors and one servo motor used, helps in movements of X, Y axes. Two CD Drives are used for the movement on axes. Microcontroller is used to controls the proper synchronization of these three motors during the process. The motors winding voltages were displayed on the oscilloscope during the printing process to investigate the synchronization between the three motors. Arduino bases software language is used to operate this machine. Inputs are given though Arduino. The design ofthe circuit issimple, inexpensive and can beaccomplishedusing commercially available components. This machine will be implemented in a miniature structure. To keep it low space occupied and light weight we will use wooden or aluminum parts to implement this structure of project[3] II. RELATED WORK From this module we describe the design and structure of small two dimensional CNC router, monitoring system and controlling system. Previous systemsusedthreedimensional CNC machines to implement their structures. In old papers CNC machine systems was suitable for designing metallic and non-metallic materials. Using three axis. The three axes are X, Y and Z respectively. The biggest drawback of these systems was complexity of connections, complexity of working of tools and small machines used, difficulty to understand each part, costly, high weight and occupies a bit of more space. To overcome these problems we proposedan idea of designing two axis CNC plotter machine which is low in weight as compared to old implemented CNC plotter machines. It is possible because of two axis and wooden materialwithcompactsize. It can be made more lightweight by using aluminum parts for construction of this system. In our system we have to convey instructions to the machines by using software whichwill be installed in computerdevice or laptops which contains G-Codes to operate CNC plotter system. Inputs will be given to Arduino. Then further operation is carried out by stepper motors and servo motor. As per the commands laser starts to move along XandYaxes and engrave the images on given object. And the laser module is controlled by laser driver[5] III. SYSTEM DESIGN The working of CNC plotter can be explained with the following steps. A. Connecting and assembling. The first step includes connecting arduinoand L293Dmotor driver properly, connecting CD drivers, stepper motor and servo motor driver shield. A laser or a pen is also added which will help us in the process of engraving. IJTSRD31834
- 2. International Journal of Trend in Scientific Research and Development (IJTSRD) @ www.ijtsrd.com eISSN: 2456-6470 @ IJTSRD | Unique Paper ID – IJTSRD31834 | Volume – 4 | Issue – 5 | July-August 2020 Page 365 For laser engraving, the pen is replaced with the laser which will perform engraving operations for engraving logos and trademarks [1] Fig.1 CNC plotter B. Software processing and Engraving. For the software part, we use arduino programming and inkscape software. The arduinowill read the inputs given to it and convert into an output that isactivatinga motor while the inksacpe software is a graphics editor which we use to create border and convert image or text into g code files and hence save our g code files. We need to convert this images and texts into codes so that our machine understands. Whenever a code is uploaded, the arduino commands the motors to operate. With the help of stepper drivers, the stepper motor starts working and moving along axis. The laser is connected with the help of a laser screw. This screw helps in the movement of the laser along the axis X,Y or Z. In this way, the laser will start working that is it can start engraving by burning or evaporating the material. During the process of laser engraving, the laser impinges on the materialwhichcreates a greatamount of heat. This heatcan change the colour, create a contrast depending upon the amount of time of heat or the exposure. Hence burning or evaporating the material [7] IV. DESCRIPTION OF UNIT 1. Power supply: It is a component which converts one type of electrical energy to other like mechanical or chemical energy into electrical energy. At least one electric load can be operated using power supply. For example, a computer is a device which converts AC power to several DC voltages. 2. Stepper motor: Fig. 2 Stepper motor A stepper motor is a synchronous, brushless motor which divides full rotation in number of steps. An electromechanical devicewhichconvertselectricalenergyto mechanical energy is called stepper motor. As long as the motor is sized to application, the position of motor can be controlled without any feedback mechanism. Generally, stepper motors are DC motors which have multiple coils moving in discrete steps. 3. Servo motor: Fig. 3 Servo motor A servo motor is a device whichallows precise controlonthe moments like push or rotate. It is a device which operates through servo mechanism. By using servo motor we can rotate an object to desired angles or distance. Servo motor, because of these features is used in many applications like robotics or automated manufacturing. 4. G-codes: G-codes are used to command any computerized machine how to perform a specific task like simple moves or functions like drilling. EachG-code hasa group numbereach group has commands for specific subject. 5. Ardiuno uno: Fig. 4 Arduino Uno It is a microcontroller based on microchip ATmega328P microcontroller. It can be used to interface many shields (boards) and variouscircuitsas ithas 14 digitaland6analog input/output pins. These pins can be programmed using Arduino IDE with USB cable. Arduino provides with the facility of communication with computer or other arduino board where ATmega328Pis used for serialcommunication.
- 3. International Journal of Trend in Scientific Research and Development (IJTSRD) @ www.ijtsrd.com eISSN: 2456-6470 @ IJTSRD | Unique Paper ID – IJTSRD31834 | Volume – 4 | Issue – 5 | July-August 2020 Page 366 Features of Arduino A. Microcontroller ATmega 328 B. Operating Voltage5V C. Input Voltage7-9V D. Digital I/O Pins 14(of which 6 provide PWM output) E. Analog Input Pins 8(of which 4 are broken out onto pins) F. DC Current per I/OPin40mA G. Flash Memory 32 KB (2K Bused by boot loader) H. SRAM 2 KB I. EEPROM 1 KB J. Clock Speed 16 MHz 6. X-Y-Z axis stepper drivers: These stepper drivers are used to control the movement over X, Y and Z axis. In X direction the stepper motor will move left and right in Y direction the stepper motor will move front and back and in Z direction the stepper motor will move up and down. These are easy-to-use stepper drivers which are mounted on the arduino. By using these drivers stepper motor current can be controlled.Thestepper driver will rotate the lead screw which in turn will control the movement of pen/laser. 7. Laser: Here the laser used is Focusable Laser Module 200-250 mW 650 nm. The outer metal housingwork asa Heat sinkfor the laser diode. It has focusable lens for the adjustment of laser dot. The laser wire terminal is connected to the laser socket on the driver board. V. ADVANTAGES For drawing blueprints on paper surface. Creating complex designs. Engravingcomplex designs on metalorwoodensurfaces To replace human labor. To increase machine work. To increase the speed of operation Negligible proportion of defective items. Material efficiency – waste minimization. Flexibility and efficiency of production. Energy efficiency. Ability to use shorter production cycles. Automation and independence of the production process. Ease of use and manufacture of devices. Versatility – anything in a form of picture. Possibility of machining of a variety of materials. Quick change in manufactured product /design. A. Laser engraver: By replacing the pen with lasermachine we can perform laser engraving operations for engraving different logo, trademarks, benchmarks etc. B. 3 Dimensional Printing: By replacing the pen with 3 D extrusion pen, we can perform 3 D modeling which is the fastest growing technology. C. Laser cutter: Instead of using pen laser cutters can be used for high precision machining operations. D. Milling operations: Different milling operations such as slotting, grooving etc. can be performed provided with over arm and arbor [5]. VI. CONCLUSION In this project, a small scale CNC Plotter with laser engraver is designed and analyzed. The Special Application CNC engraving machine based on Arduino is designed. The Arduino based CNC machine has 3 axis motions which communicates with the Arduino board which in turn drives the stepper motor drivers which run the stepper motor. The motor load calculationswere done on no load condition and suitable allowance for machining is provided. This system functioning onG-codes and Arduino asits brainispossibleto engrave complex images and designs on any kind of surface [1] VII. REFERENCES [1] Udit Pandey, Swapnil Raj Sharma, “Model and Fabrication of CNC Plotter Machine”, International Journal of Advanced Research in Computer and Communication Engineering ISO 3297:2007 Certified Vol. 6, Issue 6, June 2017. [2] Harsh B. Panchal, Mayur S. VAJA, Priyanka D. Patel, Uday N. Padia, “ARDUINO BASED CNC MACHINE”, International Journal of Research In Science & Engineering Special Issue 7-ICEMTE March 2017. [3] Aneeta Pinhiero, Beljo Jose, Tinsemon Chacko, Nazim TN, “Mini CNC Plotter”, INTERNATIONAL JOURNAL OFINNOVATIVE RESEARCH IN ELECTRICAL, ELECTRONICS, INSTRUMENTATION AND CONTROL ENGINEERING Vol. 4, Issue 4, April 2016. [4] Kajal J. Madekar, Kranti R. Nanaware, Pooja R. Phadtare, Vikash S. Mane, “Automatic mini CNC machine for PCB drawing and drilling” International Research Journal of Engineering and Technology (IRJET), Volume: 03; Issue: 02; Page No. 1106-1110; 2016. [5] JamesFloyd Kelly, Patrick Hood-Daniel,Buildyourwon CNC machine (The United States of America, Paul Manning, 2009) [6] Advertisement. Home Improvement Made Easy with New Lower Prices | Improve & Repair with The Home Depot. Web. 25 Apr. 2011. htt://www.homedepot.com. [7] ATmega48A/48PA/88A/88PA/168A/168 PA/328/328P Datasheet, Atmel Corporation, Aug. 2010, http://www.atmel.com/dyn/resources/prod_documen ts/doc8271.pdf. [8] Closed, Soldering Sj2. “Easy Driver Stepper Motor Driver.” SchmalzHaus.com Brian SchmalzHomepage. Web. 08 Apr. 2011. http://www.schmalzhaus.com/EasyDri ver. [9] CNC Machine Manufacturers. Photograph. Review about CNC Machine. Web. 25 Apr.2011. http://www.cncmachine-details.info/cnc- machinemanufacturers.html. [10] “Design Fundamentals for Phototransistor Circuits.” Fairchild Semiconductor, 30 Apr. 2002. Web. 25Apr. 2011. https://www.fairchildsemi.com/application- notes/AN/AN-3005.pdf.