SECTION A: ARDUINO BOARD

Fig 1.
Arduino Uno board

1. ATMEGA328P
MICROCONTROLLER

FUNCTION: ATMEGA328P
is a microcontroller from the AVR family; it is an 8-bit device, which means
that its data-bus architecture and internal registers are designed to handle 8
parallel data signals.

It has 3 types of memory:

·        
FLASH
MEMORY: It is used for storing application, which explains
why you don’t need to upload your application every time you unplug Arduino
from its power source.

·        
SRAM
MEMORY: Storing variables used by the application while it’s
running.

·        
EEPROM
MEMORY: It is used to store data that must be available even
after the board is powered down and then powered up again.

VOLTAGE/CURRENT RANGE:

·        
ATMEGA 328P microcontroller accepts supply voltages
from 1.8V to 5.5V.

·        
Current range: +40mA

·        
Operating frequency:16MHz

OUTPUT VALUE(S): Current: -40mA

APPLICATIONS:

This product helps the automotive OEM’s develop vehicles that are safer,
cleaner, more fuel efficient and more reliable.

·        
APS control system,

·        
Camera vision system,

·        
Controller area network (CAN),

·        
Capacitive discharge ignition,

·        
LED Lighting,

·        
Remote keyless entry,

·        
Smart actuators,

·        
Wiper controller systems.

2. IN-CIRCUIT
SERIAL PROGRAMMER (ATMEGA328P MICROCONTROLLER)

FUNCTION: In-System
Programming (ISP) is a technique where a programmable device is programmed
after the device is placed in a circuit board. ICSP is an enhanced ISP
technique implemented in microchips one-time programmable (OTP) and FLASH RISC
microcontroller unit. Use of only two I/O pins to serially input and output
data makes ICSP easy to use and less intrusive on the normal operation of the
microcontroller unit.

VOLTAGE/CURRENT RANGE:

·        
Voltage range: 5V

·        
Current: +40mA.

APPLICATIONS:

·        
Serial communication without PC or laptop.

·        
It is also used to update Arduino software.

·        
It is a protocol used to programme Arduino.

3. 5V
VOLTAGE-REGULATOR

FUNCTION: A
voltage regulator generates a fixed output voltage of a pre-set magnitude that
remains constant irrespective of changes in its input voltage or load
conditions.

VOLTAGE/CURRENT RANGE:

Max
input voltage ranges from 7V-35V and
standby current 5 mA.

OUTPUT VALUES:

This is the basic L7805 voltage regulator, a 3-terminal positive
regulator with a 5Vfixed output voltage. This fixed regulator provides a local
regulation, internal current limiting, thermal shut-down control, and safe area
protection. Each one of these voltage regulators can output a max current of
1.5A.

APPLICATIONS:

·        
Internal combustion engine,

·        
Current regulator,

·        
Regulated dual supply,

·        
Building circuits for phone charger,

·        
Ups power supply circuits,

·        
Portable CD player etc.

4. 16MHz
RESONATOR

FUNCTION: It
is use to generate clock signals.

It is an electronic component consisting of a piece of piezoelectric
ceramic material with two or more metal electrodes attached. When connected in
an electronic oscillator circuit, resonant mechanical vibrations in the device
generates an oscillating signal of a specific frequency.

VOLTAGE/CURRENT RANGE:

·        
Voltage: 5V

·        
Current: 40mA

 

APPLICATIONS:

·        
It can used as a source of the clock signals for
digital circuits.

·        
It is used in circuitry in TV’S, automotive electronic
devices, telephones etc.

·        
It can be used as a signal generator in an electronic
circuitry.

5. P-CHANNEL
MOSFET

FUNCTION: How
to drive P-channel MOSFET with ATMEGA328P MICROCONTROLLER?

P-channel MOSFETs are useful for switching positive supply of a target
circuit ON and OFF. Particular attention must be placed to the target circuit
ensuring that the supply voltage is greater than the microcontroller’s logic
voltages.

VOLTAGE/CURRENT RANGE:

Voltage:
-5V

Current:
-4amps.

APPLICATIONS:

·        
MOSFET can be used as a switch to operate a DC motor.

·        
Controlling the intensity of an array of LEDS

·        
Switching lamp.

·        
Switch mode power supplies, variables frequency
drives.

·        
Radio systems use MOSFETs as oscillators or mixers to
convert frequencies.

 

SECTION
B: WIRING DIAGRAM

Informal wiring diagram of a
Servo-Actuator-Potentiometer setup with Arduino Uno board:

 

Fig2. Wiring
diagram

The potentiometer
terminals are wired so that its middle pin( green)  is connected to analog input 0 on the Arduino
Uno board, and its two outer pins( orange and blue)  are connected to power +5V and ground.

The
servo motors have 3-wires: yellow (SIGNAL), blue (POWER) and red (GROUND).

The signal pin wire (yellow) is connected to a digital pin 9 on the digital
output, the power wire (blue) is connected to the 5V pin on Arduino board and
the ground wire (red) is connected a ground pin on the Arduino Uno board.

WHY
HAVE YOU CONNECTED IT TO A DIGITAL/ANALOGUE PIN?

1. The 10 k? potentiometer’s middle pin is connected
to the analog input pin.

When the shaft of the potentiometer is turned, the amount of resistance
can be change on either side of the wiper which is connected to the centre pin
of the potentiometer. This changes gives the different analog input, relative
“closeness” of the pin to 5volts and ground. When the shaft of the
potentiometer is turned all the way in one direction, there are 0volts going to
the pin, and we read 0. When the shaft is turned all the way in the other
direction, there are 5volts going to the pin and we read1023. In between,
analogRead() returns a number between 0 and 1023 that is proportional to the
amount of voltage being applied to the pin.

2.  The signal
pin wire (yellow) is connected to a digital pin 9 on the digital output.

The
amount of time the servo will be ON and OFF depends on the value obtained by
analogRead().

Digital
pins configured as OUTPUT with Pinmode() are said to be in a low-impedance
state. Output digital pins can provide a substantial amount of current to
servo. ATMEGA pins can source +40mA or sink -40mA of current to servo. This
current is enough to run servo motor.

IS IT
NECESSARY FOR A RESISTOR TO BE INCLUDED AND WHY?

RESISTOR: “A
resistor is a passive electrical component with the primary function to limit
the flow of electric current”.

The potentiometer is an electric instrument that is used for measuring
voltage by comparison of an unknown voltage with a known reference voltage. A
fraction of a known voltage from a resistive slide wire is compared with an
unknown voltage by means of a galvanometer.