Design Strategy For An Infrared Thermometer HND - Eet
Design Strategy For An Infrared Thermometer HND - Eet
Design Strategy For An Infrared Thermometer HND - Eet
FPN/SET/2022/2023/HEET/PT/896
FPN/SET/2022/2023/HEET/PT/905
FPN/SET/2022/2023/HEET/PT/929
FPN/SET/2022/2023/HEET/PT/934
DEPARTMENT OF ELECTRICAL/ELECTRONIC
ENGINEERING TECHNOLOGY
SCHOOL OF ENGINEERING TECHNOLOGY
FEDERAL POLYTECHNIC NASARAWA
P.M.B 001 NASARAWA, NASARAWA STATE
FEBRUARY, 2024
Design Strategy for an Infrared Thermometer
By
FPN/SET/2022/2023/HEET/PT/896
FPN/SET/2022/2023/HEET/PT/905
FPN/SET/2022/2023/HEET/PT/929
FPN/SET/2022/2023/HEET/PT/934
FEBRUARY, 2024
II
Declaration
We hereby declared this project is all my/our own work and has not been copied in
part or in whole from any other sources. All previous project work, publications,
books, journals, magazines, internet sources have been adequately referenced within
FPN/SET/2022/2023/HEET/PT/896
FPN/SET/2022/2023/HEET/PT/905
FPN/SET/2022/2023/HEET/PT/929
FPN/SET/2022/2023/HEET/PT/934
Head of Department
Signature:
Date:
III
Letter of Transmittal
Department of Electrical/Electronic
Engineering Technology
P.M.B 001
Nasarawa state.
Electrical/Electronic Technology
Nasarawa.
Dear Sir,
In compliance with the policy of the institution, which stipulates that every student at
the end of his//her programme in the school is expected to carry out a supervised
Yours faithfully
IV
Acknowledgements
I give thanks to Almighty God for His guidance, provision and protection over my life
My gratitude also goes to my Supervisor Mohammed Jamiu Abdul Salam for his
relentless support and guidance throughout the course of this study, and also to the
Technology both academic and non-academic staffs, for their massive support and
doctrine.
V
Table of Contents
Item Page
Title Page………………………………………………………………………….. i
Declaration ……………………………………………………………………….. iii
Letter of Transmittal………………………………………………………………. iii
Acknowledgement ……………………………………………………………….. iv
Table of Content ………………………………………………………………….. v
List of Figures ……………………………………………………………………. vi
List of Tables ……………………………………………………………………... vii
Definition of Terms ………………………………………………………………. viii
Abstract …………………………………………………………………………… ix
Chapter 1
Chapter 2
Chapter 3
VI
List of Figures
Figure Page
VII
List of Tables
Figure Page
VIII
Definitions of Terms:
IX
Abstract
X
Infrared Thermometer Introduction
Chapter 1 - Introduction
1.1 Background
Body temperature is the most basic and vital indicator of life. Measuring body
temperature plays an important role in daily care. However, in the face of people's
pursuit of a fast and safe lifestyle nowadays, the traditional mercury thermometer
needs to measure about 5 minutes under the armpits and needs to be read by human
eyes. Therefore, there are many drawbacks. With the development of infrared
technology, infrared thermometers have also been recognized by the public due to
their safety and rapidity (1). Although the price of traditional mercury thermometers is
cheap , the existing problems are as follows when it is used: Mercury thermometer
must contact with the human body , and temperature measurement process need lasted
5 to 10 minutes, because infants is active, let parents become very headache for infant
body temperature; And in the number of temperature meter reading, easy to read
wrong due to external light and other factors; Mercury thermometer is easy to rupture
when heated or stored improperly, It can lead to mercury poisoning due to human
thermometers are replaced by the safer and more convenient electronic thermometers
at the sublingual, armpits, ear canals, and in some rare occasions, the rectum and
axillary for accuracy (3). Many of these surface measurement sites, specifically the
temporal and central forehead, reflect lower readings than internal sites such as the
tympanic temperature readings, the current gold standard to represent the body core
resolution, and stability required for many potential applications. Temperature sensors
surface via conductive or convective heat transfer are problematic because they
require intimate contact with the surface, which affects the local surface energy
balance and thus temperature; the small sampling area of such sensors can also be an
that integrates the effects of spatial heterogeneity (6). However, Infrared (IR)
thermometers can fulfil this gap by measuring the surface temperature without direct
emitted by the object. Additionally, these thermometers are now commonly used in
clinical practices (5), as well as routinely during the pandemic for self-monitoring and
molding (due to mold production and tooling costs), producing significant waste
manufacture with significantly less waste. Coupling with 3D printing, the use of ‘off-
the-shelf’ microcontroller kits such as Arduino, Raspberry Pi, and Micro: bit can now
specificity between 75.4% to 99.6%, and a positive predictive value between 0.9% to
76.0%. In fact, there are recommendations for its repeated measurements at hospital
gantries (11), given that IR thermometers are highly prone to external interferences by
surrounding temperatures, relative humidity (5), the site of measurement, and the
presence of oil (sebum) and sweat on the forehead, as well as other factors in the
immediate environment (12). Apart from these innate factors, intrinsic human
physiological factors such as fever or exercise can produce sweat to affect the
and humidity that affect blood supply to the skin surface, which by generally lower
than the expected body temperature (4,12), many IR thermometers, especially self-
assembled ones can be inaccurate as they lack ambient temperature and distance
At the point of writing, many IR sensors have in-built radiation emitter and receiver
distances. Yet, the onus is still on the user to operate them correctly for accurate
measurements. This means that, compared with the traditional thermometer, the
infrared thermometer is safe to use and has convenient measurement and short
measuring time. Therefore, the research on infrared thermometer design has important
The problem being addressed is the need for a well-thought-out design strategy for an
their non-contact nature and ability to measure temperature quickly and accurately.
However, many existing infrared thermometers on the market suffer from design
flaws that affect their usability, accuracy, and overall user experience. The primary
product. The design strategy will focus on several aspects; ergonomics will play a
comfortable to hold and operate for extended periods, as it should consider factors
like weight distribution, grip contour, and button placement to ensure minimal fatigue
during usage; accuracy is another critical aspect of an infrared thermometer, and the
design strategy will address this by incorporating advanced technology and algorithms
buttons for easy operation. The design should minimize the learning curve for new
users and provide a seamless experience for both professionals and individuals with
limited technical knowledge. The design strategy will focus on minimizing production
1.3.1 Aim
accurate measurements.
1.3.2 Objectives
ment capabilities.
invasively, especially during the ongoing COVID-19 pandemic. They are widely used
places to quickly and efficiently screen individuals for potential fever symptoms.
Conducting a study on the design strategy for an infrared thermometer is crucial for
allows for improvements in accuracy, user experience, speed, adaptability, and cost-
years, particularly in the domain of infrared (IR) sensor systems. IR sensors play a
effective design strategy for IR sensor systems. Despite the notable progress achieved
in IR sensor technology, there are still gaps in the existing design strategies. This
study endeavors to identify these gaps and bridge them by proposing innovative
design approaches that can significantly improve the performance, efficiency, and
1.5.1 Scope
accurate copper core probe, it has backlight display. Accurate detection of health
status, when the measurement results are in the orange high temperature or red high
temperature, the backlight will be different, easy to watch. Intelligent calibration and
convenient to observe the cycle and control the temperature changes whenever
necessary.
1.5.2 Limitations
The study's recommendations may need to adapt to changing market dynamics and
The rest of the paper is organised as follows; Chapter two presents the literature
review of the study, chapter three describes the methods applied, chapter four
discusses the results of the work, chapter five summarizes the research outcomes and
the recommendations.
strategies for infrared thermometers, highlighting areas for further exploration and
thermometers have gained significant popularity in recent years due to their non-
literature review aims to explore the design strategies employed in the development of
challenges that designers face. By reviewing relevant research and articles, this review
aims to provide insights into the current state of design strategies for infrared
the design strategy for an infrared thermometer involves several key considerations,
2.2.1 Infrared
Infrared (IR) refers to a type of electromagnetic radiation that falls within the
beyond the visible light spectrum, which makes it invisible to the human eye (14).
its ability to carry thermal energy. This feature allows objects to emit and exchange
heat energy in the form of IR radiation. Infrared radiation is emitted by all objects
February 2024 Authur 2, Authur 1, Authur 3 8
Infrared Thermometer Literature
with a temperature above absolute zero, including humans, animals, and inanimate
objects. Infrared technology takes advantage of this property for various purposes.
Similarly, Far-infrared (FIR) is utilized in heating systems, such as space heaters and
saunas, where it efficiently warms objects without affecting the surrounding air (14).
and sensors play a significant role in surveillance systems, enabling night vision
capabilities for security purposes. Infrared spectroscopy aids in chemical analysis and
Infrared communication is also widely utilized in remote controls for TVs, DVD
data transfer between devices, such as smartphones and computers via features like
Infrared systems trace their origins to the year 1800 when John Frederik William
(17).
thermoelectric effect, and soon thereafter, in 1829, Leopoldo Nobili created the first
enabled the study of the solar irradiance far into the infrared spectrum.
possible after John Bardeen and William Shockley invented the transistor in 1947.
production in 1966, and in 1969, the charge-coupled device (CCD) was developed by
the design and fabrication of complex focal plane arrays. Three generations of
systems may be considered for the foremost military and civilian applications. The
populated linear array elements. These devices did not include multiplexing functions
in the focal plane. Monolithic and hybrid detector FPA technology with multiplexing
read-out circuitry in the focal plane belong to the second-generation systems. Third-
generation FPAs are being actively developed and contain several orders of
magnitude more pixel elements than the second-generation, as well as many other
In 1654, Ferdinand II de’ Medici, Grand Duke of Tuscany, produced sealed tubes
with a bulb and stem that were partly filled with alcohol. This was the first
unique as there was no standard scale. Christian Huygens in 1665 suggested using the
astronomer Ole Rømer in Copenhagen used these upper and lower limits for a
thermometer that he used to record the weather. There was still uncertainty about how
well these parameters would work at different geographical latitudes. In 1694, Carlo
Renaldini suggested that the ice and boiling water limits should be adopted as a
Temperature scales are essential tools for understanding and quantifying thermal
around arbitrary zero points, scale dependence, and negative values remain.
scales, striving for universal standards and improved accuracy. The scale that were
inscribed scale with greater reproducibility. It was this that led to their general
adoption. Fahrenheit first calibrated his thermometer with ice and sea salt as zero. Salt
water has a much lower freezing point than ordinary water, so he chose the freezing
point as 30 °F. The temperature inside the healthy human mouth was 96 °F, and he
established the boiling point of water at 212 °F. He later adjusted his freezing point to
number of different thermometers, all with different scales. He may have already at
that early stage in his career realized that there was a need for a common international
scale. He was appointed as professor of astronomy at Uppsala (as his father had been
before him) and was involved in meteorological surveys. Celsius was the first to
international temperature scale based on scientific data. (He was for many years
that the freezing point is independent of latitude and atmospheric pressure (21).
In Scotland in 1848, Lord Kelvin realized in his study of heat that a much greater
range of temperature could be considered, far beyond the centigrade scale. Absolute
zero, the level at which all molecular motion stops, gives the lowest conceivable
centigrade scale and −459.67 degrees on the Fahrenheit scale. Therefore, the lowest
temperature on the Kelvin scale is 0, and the units are the same as the centigrade
(Celsius) scale. While this scale is not used in clinical medicine, it may sometimes be
thermal energy between a system and its surroundings, based on the fundamental
into:
based on the principle that substances expand or contract with changing temperature.
strips. As the temperature changes, these materials expand or contract, and the
temperature.
The behaviour of gases under different temperatures and pressures can provide
valuable information about temperature. The ideal gas law (PV = nRT), relating the
pressure (P), volume (V), amount of gas (n), and temperature (T), is a fundamental
Temperature is often measured using electrical signals and sensors. Several electrical
object. The principle of Planck's radiation law, which describes the intensity and
Devices like infrared thermometers or thermal cameras use this principle to capture
equilibrium. When two objects are in thermal equilibrium, their temperatures are
equal, and heat energy transfers between them stop. This principle is used in
Thermometers come in different forms, and they rely on different thermal properties
of materials for their operations. The following are sone of the more common types of
thermometer;
temperature. It typically consists of a glass tube filled with a liquid such as mercury or
alcohol. As the temperature changes, the liquid expands or contracts, causing it to rise
or fall within the tube. The temperature is then read off a scale marked on the tube
(26).
hazards associated with mercury, many countries have phased out their use in certain
Liquid thermometers come in various designs, but they typically consist of a sealed
glass tube with a bulb at one end containing the liquid. The glass tube is thin and
uniform to ensure accurate temperature transfer, and the liquid inside has a known
The liquid used in these thermometers can vary depending on the specific application
and temperature range required. Mercury was a commonly used liquid due to its low
freezing point and high thermal conductivity, allowing for accurate measurements
even in extreme temperatures (26). However, mercury has toxic properties, and its use
has been restricted or phased out in many countries due to environmental concerns.
Liquid crystal thermometers are rarely used and only by the same patient. The
temperature. The color changes are reversible, while the re-use of this type of
thermometer may occur after about a minute from the previous reading. The
measurement time should be 1 minute in the mouth and 3 minutes in the armpit. The
are often used in modern liquid thermometers. These liquids have lower toxicity and
are less harmful to the environment compared to mercury. They have lower thermal
various industries, scientific research, and everyday applications. They are commonly
when any conductor is subjected to a thermal gradient, it will generate a voltage. This
is now known as the thermoelectric effect or Seebeck effect. Any attempt to measure
this voltage necessarily involves connecting another conductor to the "hot" end. This
additional conductor will then also experience the temperature gradient, and develop a
voltage of its own which will oppose the original. Fortunately, the magnitude of the
effect depends on the metal in use. Using a dissimilar metal to complete the circuit
creates a circuit in which the two legs generate different voltages, leaving a small
temperature, and is between 1 and 70 microvolts per degree Celsius (µV/°C) for
changes over temperature. Thermocouples are constructed from two wire leads made
from different metals. The wire leads are welded together to create a junction. As the
temperature changes from the junction to the ends of the wire leads, a voltage
develops across the junction (29). Combinations of different metals create a variety of
voltage responses. This leads to different types of thermocouples used for different
include the temperature accuracy, durability, conditions of use, and the expected
service life (30). Thermocouples are widely used in science and industry; applications
include temperature measurement for kilns, gas turbine exhaust, diesel engines, and
other industrial processes. The dissimilar metals are joined at a temperature sensing
temperature (TCJ) through the two metals. The leads of the thermocouple are required
to be at the same temperature and are often connected to the ADC through an
the ideal gas laws. A gas thermometer is a primary instrument for determination of
complicated devices inconvenient for practical use. In practice, temperature scales are
used in which a simple and convenient secondary thermometer is used and methods of
the primary instruments), i.e., representing the so-called fixed points and, of course,
the secondary thermometer itself together with simple and convenient methods for its
The most common way to measure the temperature of an object is through the heat
conduction between the object and the heat-sensitive element, and therefore requires
contact between the transducer and the object (32). This can be a problem if the object
is moving, like an incandescent piece in the industrial production line, or the contact
of the object with the heat-sensitive element is not allowed due to its fragility, as for
intensity that depends on its temperature, that is, electromagnetic energy radiates from
all matter, regardless of its temperature (32). Different materials radiate with different
including skin, are very efficient, frequently exhibiting emissivities of 0.95 and this
amount of radiation emitted by the skin is used to quantify the human body
The highest possible emissivity, unity, is accounted to the ideal emitter of electro-
magnetic radiation, called black body; black because it is not reflective at any wave-
length and it is not transparent, but opaque. The radiation intensity varies with
temperature and with the wavelength. Figure 5 shows the spectral power of a black
body at different temperatures in the wavelength range from 0.1 to 2 μm. Within this
electromagnetic radiation range lies the visible light (0.4 – 0.724 μm) and part of the
infrared spectrum (0.724 – 100 μm). When the temperature of a black body increases,
the overall radiated energy increases and the peak of the radiation curve moves to
Figure 6. Spectral power of a black body at different temperatures and wavelengths (32).
Temperature sensors are devices designed for measuring the degree of coolness and
hotness in an object. The voltage across the diode determines the working of a
diode’s resistance (35). According to Cengiz et al. (35) The cooler the temperature,
the lesser the resistance will be and vice-versa. A measurement of the resistance
across the diode is done, and the measurement is converted into units of temperature
that are readable and displayed in numeric form over readout units. In the field of
Temperature sensors are found in different types, sizes, and shapes. There are two
temperature sensors.
According to Kuzubasoglu & Bahadir (36), a few temperature meters are capable of
with the object. These types of temperature sensors fall under the class of contact-type
sensors. They can be utilized in the detection of liquids, solids, or gasses over a broad
range of temperatures.
These types of temperature meters do not measure the temperature of an object while
in direct contact; rather, they measure the degree of hotness or coldness from the
radiation that is emitted by the heat source (36). The contact and non-contact
temperature sensors are divided further into the following mentioned types of
temperature sensors.
This is known as the resistance thermometer and uses the resistance of the RTD
element with temperature to measure the temperature. Different types of materials can
be used to make the metal. The materials include nickel, platinum, and copper.
However, platinum is the most accurate and therefore the most expensive (36).
B. Thermocouple Sensor
Thermocouple sensors have two wires made of different metals connected at two
points. The voltage between the two wires reflects the change in temperature.
Although their accuracy may be slightly reduced to a degree that is lower than an
RTD, they have a temperature range between -328°F to 3182 °F (-200 °C to 1750 °C)
Thermocouples are separated into types, with each type being suitable for specific
Type N -270 to 1300 0 to 1100 -40 to 1000 -40 to 1200 -270 to 1304
Type R -50 to 1700 0 to 1600 0 to 1600 0 to 1600 N/A
Type S -50 to 1750 0 to 1600 0 to 1600 0 to 1600 N/A
Type T -250 to 400 -185 to 300 -40 to 350 -40 to 350 -250 to 404
Type B 0 to 1820 200 to 1700 N/A 600 to 1700 4 to 1820
Source (Machin et al., 2018)
C. Infrared Sensors
the amount of thermal radiation that is being emitted by a heat source or object. These
environments, where a safe distance must be maintained away from a particular body
(38).
applications due to their non-contact nature, quick response time, and accurate
temperature measurement capabilities. Over the years, several modern trends have
the devices. This allows for more compact and portable models, making them easier
purposes.
Infrared thermometers are now being equipped with additional features and functions,
incorporate built-in humidity sensors, laser pointers for improved targeting, data
infrared thermometer design. This includes incorporating backlit LCD screens with
temperature readings. These improvements make the devices more accessible and
impact-resistant materials, and protective features like dust and water resistance. With
warning systems to extend the device's operational time and minimize downtime (42).
Infrared thermometers are designed with safety considerations in mind. Some models
incorporate audible and visual alarms to alert users when measured temperatures
them with other technologies (42). These advancements aim to provide users with
readings. Understanding the appropriate distance and target site for each specific
thermometer is crucial for accurate readings. The researcher will consider the overall
cost while choosing a design, as prices can vary depending on features and
complexity. Choose a thermometer that meets your needs and budget. Another is the
versatility such as for professional or medical use, unlike Feng (42); Long (39), the
researcher will ensure the thermometer complies with relevant regulations and
standards.
Switch, Case, Vero Board, soldering lead, soldering flux, soldering iron, and LCD
Module.
The design of Infrared digital thermometer was obtained both from primary and
secondary source. Primary data were collected from various knowledge on the
electronic. Secondary data on the other hand were obtain by searching the internet and
text books
The design of this " Infrared digital thermometer" system comprises of different
modules (parts) brought together to form the overall design. Each of these modules is
purpose.
These different unit cannot function alone; they all need to function together to
The hardware comprises of the physical part of the design. It shows the physical
components and how they are connected together to-achieve the whole system design.
This is the basic voltage input source of the diagram. It supplies the power to the
design. The output from the source is rated +3V. it consist of a DC power supply
which is obtained from a 3volt battery cell, a 3volt voltage regulator was used to
obtain a constant output of 3 volt which was used to supply power to the system.
(datasheet). It has 14 digital input/output pins (of which 6 can be used as PMW
output), 8 analog inputs, an onboard resonator, a reset button; and holes for mounting
pin headers, A six pin header can be connected to an FTDI cable or spark fun
exhibitions. The board comes without pre-mounted headers, allowing the use of
various types of connectors or direct soldering of wires. The pin layout is compatible
There are two version of the pro mini, one runs at 3volts, and 8 MHz, while the other
at 5V and 16MHz.
LCD Display
Infrared
(Atmega 328)
Temperature
Sensor Microcontroller
Power
Supply
The Arduino pro mini can be powered with an FTDI cable or breakout board
connected to its six-pin header, or with a regulated 1.8 v or 5.5V supply (depending
on the model) on the VCC pin. There is a voltage regulator on board so it can accept
3.4.4 Memory
The ATmega328 has 32 kB of flash memory for storing code (of which 0.5 KB is
used for the bootloader). It has 2kB of SRAM and 1kB of EEPROM (which can be
Each of the 14 digital pins on the pro mini can be used as an input or output, using pin
Mode, digital Write, and digital Read functions. They operate at 3 or 5 volts
(depending on the model), each pin can provide or received maximum of 40mA and
3.4.6 Communication
The Arduino pro mini has number of facilities for communicating with a computer,
serial communication, which is available on digital pins 0 (RX) and 1 (TX), the
Arduino software includes a serial monitor which allows simple textual to be sent to
and from the Arduino board via USB connection. A software serial library allows for
software includes a wire library to simplify use of the I 2c bus; see the reference for
details. To use the SPI communication, please see the ATmega328 datasheet.
3.4.7 Programming
The Arduino pro mini can be programmed with the Arduino software. The
ATmega328 on the Arduino pro mini comes pre--burned with a bootloader that allows
you to upload new code to it without the use of an external hardware programmer. It
the thermal radiation sometimes called the blackbody radiation emitted by the object
being measured. They are sometimes called laser thermometers If a laser is used to
describe the device's ability to measure temperature from distance. By knowing the
amount of infrared energy emitted by the object and its emissivity, the object's
due to reflection of radiation from a hotter body even the person holding the
instrument rather than radiated by the object being measured, and to an incorrect
assumed emissivity.
The design essentially consists of a lens to focus the infrared thermal radiation on to a
detector which converts the radiant power to an electrical signal that can be displayed
permits temperature measurement from a distance without contact with the object to
LCD (Liquid Crystal Display) screen is an electronic display module and find a wide
range of applications. A 16x2 LCD display is very basic module and is very
commonly used in various device and circuits. These modules are preferred over
seven segments and other multi segment LEDs. The reason being LCDs are
A 16x2 LCD means it can display 16 characters per line and there are 2 such lines. In
this LCD each character is displayed in 5x2 pixel matrix. This LCD has two registers
The command register stores the command instructions given to the LCD.A command
is an instruction given to LCD to do a predefine task like initializing it, cleaning its
screen, setting the cursor position, controlling display etc. The data register stores the
dada to be displayed on the LCD. The data is the ASCII value of the character to be
The construction uses 3volts DC battery as source of power, with a power button at
the right side of the construction which when push down the construction will turn on
and when left untouched for 30 second it will go off and you use the same button to
turn it on.
It also has another button and the left side of it which is the reset button that is use to
switch between object and body temperature, the same button is used to switch
between degree Celsius and degree Fahrenheit unit. This construction can measure
temperature of distance 1-60 cm. The highest body, temperature it can measure is 40
C and the highest object temperature is 100℃, once any of this value is above the
The construction of this project is done by putting together all the various components
that are required for the system. The construction of this project implies putting
proposed. The phase was carried out based on the design analysis outlined. The
Layout
Soldering
The project layout design has to do with planning of the way in which the actual look
of the project appears to be. When making plan for layout design of this project, the
first thing we considered was the possibly smallest size to ensure that the project is as
portable as possible. Before beginning the layout design, we needed all the required
consideration was made which include from case to case of mounted components over
the Vero board or assess part of the present components. The entire components
needed for the project were assembled part by part before the design layout of the
project was made. It was necessary that some of the components were turn to different
angular position so that the terminals are closer to the connection of the components.
The scale was then checked by positioning the components on the squared paper or a
sample board.
The assembly and placement of components refers to the way in which the various
components are arranged on the board based on the design layout, having conducted
the layout and determined the way in which the various components are placed on the
board. Hence, the components were carefully placed on the board according to the
design,
The soldering involves the mechanical clinging of the various components unto the
board. It refers to the method by which various electrical components are being
mechanically held together on the board to form an electrical circuit. The soldering
operation is carried out using various soldering kits and the soldering operation" is
The steps and precautions observed during the process of soldering include; ensuring
the soldering iron was left to assume optimal temperature before putting it unto use;
maintaining the shortest possible contact period on the component of the soldering
iron to avoid thermal damages of the associated component, and an avoidance of too
much lead on the board as this can lead to short-circuit of various points.
Price(N)
(A Tmega328)
References