Electronic circuits use a common type of electrical component which refer as Resistors. Resistors are incredibly significant and well-liked electrical components, just like capacitors. In essence, resistors are used to control the electron flow. The amount of current flowing through the circuit can change. This guide is beneficial to you if you don’t know much about resistors. You will discover more concerning these resistors in this post.
What Is a Resistor?
The majority of electric circuits commonly contain a resistor. An electrical resistor is indeed a passive part that prevents or hinders the passage of charges. Resistance is the ability of a resistor to restrict the flow of electricity through a circuit or a component. Each electrical circuit or component possesses a particular resistance, although some might have insignificant levels that have no impact on the circuit’s current flow. Despite what might seem contradictory, resistors are crucial parts of electrical systems and circuits because of their capacity to restrict the passage of current. This property has several uses.
The equivalent of a resistor would be a little rock or another impediment within a water pipe. So when a pipe or hose attaches to a valve, and a little obstruction comes, less water flows through the pipe. A stream’s tiny plants, boulders, and logs may all be comparable as resistors. These items prevent the stream’s water from flowing continuously.
Functions Of Resistor
An electrical resistor frequently use for things like
- regulating the voltage at a particular junction of a circuit,
- limiting or adjusting the frequency range through a voice circuit,
- pulling up or down the voltage at a digital logical chip’s input pin,
- protecting LEDs and other semiconductors from power surges, and
- Limiting the rate at which a capacitor charges.
- In the last example, make a voltage regulator by connecting two resistors in series.
- If you need variable resistance, a potentiometer can be used in place of an electrical resistor.
Working Principle of Resistor
A resistor collects electrical energy while restricting current flow and lowering voltage, which it then must release as heat. The heat transfer in the majority of contemporary electronic circuits is generally less than 1µW.
Ohm’s law says the following if R represents a resistance measured in ohms, I represents the current flow in the resistor measured in amperes, & V represents a voltage drop due to the resistor:
V=I/R
Another way of expressing that a 1-ohm resistor will admit a 1 amp current flow when there is a 1-volt voltage differential between its ends.
In a Direct Current circuit, if W represents the resistance’s power output in watts:
W=V*I
We may represent watts in measures of resistance and current by substituting them with the law of Ohm:
W=I2/R
Watts is also equivalent to resistance and voltage:
W=V2*R
In circumstances where you are unsure about the current or voltage drop, these alternatives may be helpful.
When employing alternating current, there are roughly the same relationships. However, the voltage becomes a more complicated function of the resistance.
How to Make Resistors?
Resistors are useful to reduce the voltage passing across a circuit. It is a rather straightforward gadget. The middle of a resistor constructs with a substance, such as carbon, that only partially conducts electricity. The resistor’s primary function is to lower the current’s voltage. The current voltage decreases when it reaches the resistor’s portion, which possesses poor conductance.
· Carbon Resistor
The most typical kind of resistor is a carbon one. This creates when encircling a ceramic material core with carbon tracks. A machine winds the carbon tracks around the core of ceramic, or a laser engraves the track inside the core. After that, two copper leads are in the resistor’s ends so that the track’s ends touch the leads. Then, the resistor core seals with paint.
· Metal Film Resistor
The construction of a metal sheet/film resistor is fairly similar. This resistor’s ceramic core was useful in its construction. Like all resistor components, this component produces using machines. The track of metal film/sheet resistors comprises metallic oxide substances. Similarly to carbon, this exhibits semiconductive characteristics. Once more, a pressing machine is useful to put copper leads into the resistor’s ends. As a final step, these resistors go through painting.
· Processes
Resistors are almost always produced by machines. Machines are useful to press and form ceramic cores. Separate cores are designed to suit various resistor sizes. The resistor substance is then “wire coiled” all around the cores using a different machine. The ends of lead are then placed over the core, which includes the metal coil end and a cap at the end that resembles a cap of a bottle. The cores have a baked finish or standard paint.
· Resistance Values
Adding the total resistance to the component is the last step in creating a resistor. To achieve this, draw lines along the resistor’s painted core. Each line is a unique numerical value that is related to Ohms. Black, for instance, is equal to 0, brown to 1, red to 2, and orange to 3. Simple numbers appear on the initial two lines, and the multiplier appears on the third. As a result, a resistor having three bands—brown, red, and orange—would have a resistance of 12,000Ω. As a result, the resistor has a 12,000Ω resistance value.
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· Accuracy and Tolerance
Applying the resistor’s accuracy rating is the following step. This is the resistor’s accuracy or tolerance level. Carbon resistors are less precise than metal-oxidized resistors. They are identified with a greater tolerance color due to a greater tolerance rating. A gold band, for instance, is accurate to within 5%. 5 to 10 % accuracy is indicated by silver bands.
Major Types Of Resistors
Resistors come in a variety of shapes, sizes, and materials. Following, we will go through each potential type of resistor in-depth, along with its advantages and disadvantages.
Resistors come in two different categories.
- Linear Resistors
- Non-Linear Resistors
Linear Resistors
Linear resistors are those whose values fluctuate in response to temperature and voltage. In other terms, a resistor is a linear resistor if the value of the current is precisely proportional to a given voltage.
There are usually two kinds of resistors with linear characteristics.
- Fixed Resistors
- Variable Resistors
Fixed Resistors
A fixed or solid resistor is indeed a resistor that possesses a fixed value and whose value cannot be changed.
The types of fixed resistors are
- Carbon Composition Resistor
- Wire Wound Resistor
- Thin-Film or sheet Resistor
- Thick-film or Sheet Resistor
Carbon Composition Resistors
A common solid resistor is composed of a blend of insulating filler, resin binder, and powdered or granulated graphite or carbon. The real resistor’s resistance is determined by the insulating material ratio. The insulator powder or binder is shaped like a rod, and each rod’s end has two metal covers.
The resistor has two conductive wires on each end for quick soldering connections in the PCB. The rods have a plastic layer over them that is printed with various color codes that indicate the resistance level. They come in resistances ranging from 1Ω-25MΩ and with power ratings ranging from 1/4W to 5W.
Characteristics Of Fixed Resistors
They often take up less room because they are compact and extremely affordable. They come in a variety of power and ohmic levels and are trustworthy. Moreover, a solid resistor can handle the additional voltage.
Moreover, due to being less stable, they possess an extremely high TC. In comparison to other kinds of resistors, they also create a little noise.
Wire Wound Resistors
By wrapping a resistive cable around an insulating rod or core, wire-wrapped resistors are created. The insulation core is often constructed of porcelain, press adhesive paper, Bakelite, and ceramic clay. At the same time, the resistance cable is typically made of tungsten, nickel, nickel-chromium base, and manganin.
The expensive manganin wire-wrapped resistors are with delicate test apparatus like the Wheatstone bridge. They come in power ratings ranging from 2W to at least 100W. These resistors have ohmic values ranging from 1Ω to 200kΩ or even more and may be useful securely at approximately 350 °C.
Moreover, the wire-wound resistors have a rating of power of 500W. And the current value of resistance is between 0.1Ω to 100kΩ.
Advantages & Disadvantages Of Wire Wound Resistors
When compared to carbon substance resistors, wire-wrapped resistors are quieter. They function admirably in circumstances of overburden. They are dependable and adaptable, and their frequency range includes both DC and audio. The expense and incompatibility of wire-wrapped resistors prevent their usage in a high-frequency device.
Application Of Wire Wound Resistors
When high sensitivity, precise measurement, and proportional current regulation are required, such as when using a shunt including an ampere meter, wire-wrapped resistors are utilized. Moreover, wire-wrapped resistors are frequently employed in high-rated power equipment and devices, as well as in testing and measurement tools, industrial equipment, and control tools.
Thin Film Resistors
In essence, most thin film or layer resistors are constructed using a resistive substance and a high grid rod of ceramic. A durable ceramic substance or insulating glass plate, rod, or tube with a thin coating of conducting material layered over it. There are also two further varieties of thin film coating resistors.
Carbon Film Resistors
The substrate, which is an insulating core or rod constructed of high-quality ceramic, comprises a carbon-film resistor. All around the rod, just a really thin resisting carbon film or layer was applied. These resistors have a wide working range, less noise, and are more stable than pure carbon resistors, which makes them popular in electrical circuits.
Metal Film Resistors
The construction of a metallic film resistor is similar to that of a carbon-film resistor. The key distinction is the use of metal, or a combination of nickel-chromium, metal oxides, or a combination of glass and metals known as metal glaze, in place of carbon. Metal-film resistors are incredibly small, inexpensive, and functionally dependable. They are utilized in applications where consistency and low distortion level are crucial because of their very low TC (2 ppm/°C).
Thick Film Resistors
A Thick-films resistor is made using the same process as a thin film resistor, with the exception that they have a very thick film surrounding the resistive substance rather than a thin one. It is known as thicker film resistors for this reason. Two other varieties of thick-films resistors exist.
- Metal-Oxide Resistor
- Cermet Film Resistor
- Fusible Resistor
(i) Metal Oxide Resistors
A Metal-Oxides Resistor is easily made by oxidizing Tin Chloride’s thick layer over a heated substrate or glass rod. These resistors come in a large variety of resistance and exhibit excellent temperature stability. Moreover, large voltages may be employed, and there is very little operational noise.
(ii) Cermet Oxide Resistors
The interior portion of the oxidized ceramic resistors comprises ceramic insulating materials. The resistor is then covered with a layer or film made of metal alloy or carbon. It is then finally fixed in a Cermet or ceramic metal. For simple placement on PCB, they are designed in rectangular or square shapes with pins and leads located beneath the resistors. Since their value does not fluctuate with temperature, they offer reliable functioning in high temperatures.
(iii) Fusible Resistors
These resistors are equivalent to wire-wind resistors. This is a fused resistor, which means it opens or breaks the circuit when the power rating of the circuit exceeds the stated amount. It is termed a “fusible resistor” for this reason. Fusible restores serve two purposes, i.e., they restrict current while also serving as fuses.
They are commonly utilized in pricey electronic circuits such as amplifiers, TV sets, and others. Fusible resistors typically have an ohmic value that is below 10Ω.
Variable Resistors
As per the name, those resistors whose values may be adjusted manually using the right technique or using a knob, dial, or screw. These resistors possess a movable arm linked to the shaft, and by moving the arm, the resistance value may be adjusted. They are employed in the receiver of the radio for controlling tone and volume resistance.
Variable resistors’ types are described below.
- Potentiometer
- Rheostat
- Trimmer
· Potentiometer
A device with three terminals called a potentiometer is useful for regulating the circuit’s voltage level. The resistance between the first two external terminals is fixed, whereas the 3rd terminal is coupled with a Wiper that is changeable. The rotation of the wiper, which is attached to the controlling shaft, will alter the resistance value.
Such resistors are known as variable resistors and allow potentiometers to serve as voltage dividers. They come in sizes of at least 10MΩ.
· Rheostat
Rheostat is a device with at least 2 or 3 terminals. It usually operates manually to restrict current. Tapped resistors and variable wire-wrapped resistors are other names for rheostats.
The Nichrome resistance is wire wound all around the ceramic core, which is then put inside a protective cover to create rheostats. The resistor component is encircled by a band of metal. It is useful as a rheostat or potentiometer.
There are variable wire-wrapped resistors in the 1-150 Ω range. These resistors have power ratings ranging from 3-200W. Rheostats between 5 -50W in voltage level are the most popular.
Difference Between a Potentiometer & a Rheostat
The differences between a rheostat and a potentiometer are minimal. Both resistors are movable. The primary distinction is how the circuit is useful, or more specifically, for what reason do we employ the variable resistor?
For instance, Rheostats are useful when a circuit is connected between the terminals of a resistor element, where one end represents the resistor’s main end while the other represents wiper or sliding contact.
On the contrary, if we follow the same procedure as described above to regulate the voltage level, the same variable resistor turns out as a potentiometer.
· Trimmers
Trimmers are extra screws that are useful with variable resistors or potentiometers for greater performance. A little screwdriver may be useful to adjust the screw’s rotational position in order to vary the resistance value.
They range from 50 Ω through 5MΩ and comprise carbon film, carbon composition, wire materials, and cermet. Trimmer potentiometers have a rated power of 1/3-3/4 W.
Non-Linear Resistor
Non-linear resistors refer to those kinds of resistors which fluctuate the electric current in response to variations in a given temperature or voltage. Besides, non-linear resistors come in a variety of forms, but the ones that are most frequently used are listed below.
· Thermistor
A variable resistor type that can detect temperature changes is the thermostat. Simply put, it’s a two-terminal gadget that’s extremely temperature-sensitive. A thermistor’s resistance is inversely correlated with its temperature.
· Varistor Resistor
A varistor, a semiconductor-based non-linear resistor, means that the current flowing through it does not depend linearly on the given voltage through it. The most popular varistor resistors are called metal-oxide varistors or MOVs.
· Photo Resistor Or LDR
A light-dependant variable resistor is known as a photoresistor, LDR, Light-Dependent Resistor, or photoconductive unit. When the intensity of the incoming light increases, the resistance of the photoresistor lowers.
· Surface Mount Resistors
SMD resistors, often known as surface-mounted resistors, have a rectangular form. Electronic parts designed for Surface Mount Technologies or SMT are known as SMDs.
Electrical Resistors | Materials
Manufacturing a circuit part with only one characteristic, like pure resistance, inductance, or capacitance, is almost difficult. For instance, a resistor lacks resistance just but rather an affiliated capacitance and inductance. An inductor, moreover, its inductance does have, in turn, capacitance and resistance, as well as a capacitor does have resistance adding to capacitance.
You will be aware of the components useful for resistors.
A circuit element’s impurities lead to the production of residues, which are surplus amounts. Yet, a certain number is designed to dominate. This includes resistor resistance, inductor inductance, or capacitor capacitance to reduce the influence of residues and enable the design of clean circuit components within a given range of precision. This piece helped many people who questioned what materials are useful to make conventional resistors. The following provides the response to the question, “Why and What substance are typical resistance coils constructed of?”
In measurement and instrumentation activities, resistive networks and resistors are frequently utilized for resistors intended for accurate work, stability, or constancy over time, a low TCR, a low electromotive force with copper, and high resistivity. Also, resistance to corrosion, oxidation, and moisture, production simplicity, and affordability are the most important characteristics of the substance’s usefulness.
Yet no material contains all of the aforementioned characteristics; thus, only the substance that is most appropriate for the task at hand is chosen.
The components listed below are useful for creating a standard resistor:
· Manganin
It is a copper, nickel, and manganese alloy that is utilized as a resistance substance in precise resistors and equipment for measuring resistance. The nominal structure of this material is copper 84%, manganese 12%, and nickel 4%. It possesses a thermal Electromotive force of 2-3 V/°C and a resistance of 0.45-0.50*10 (exponential -6) ohm, which is roughly 25 times greater than copper. When heat is properly treated, it provides a consistent resistance value throughout time and exhibits no signs of aging.
The primary characteristic of manganin is its ability to practically have a 0 coefficient of thermal resistance at temperatures close to ambient. As an example, let’s use 0.004 %/°C at 20 °C.
· Constantan
This is a group of copper and nickel alloys having a nickel content of 40-60% and a little bit of manganese for enhancing their mechanical qualities. These alloys all have comparable electrical characteristics. To serve as thermocouple substances, they are offered for sale as constantan and under numerous trade names. They have 40 V per degree Celsius thermoelectric Electromotive forces against copper. Yet, aside from their significant thermoelectric Electromotive forces, these alloys’ electrical characteristics are strikingly comparable with that of manganin.
At normal temperatures, constantan has around 25 times the resistivity of copper, which is highly corrosion-resistant, cheap, and simple to deal with. Soft soldering this to copper is simple. When its high emfs versus copper does not constitute a drawback, it finds considerable employment. For instance, resistors made for a.c. Operations employ this material. It may also be useful in voltmeter multipliers and 1000 ohms resistors and higher if the thermal em-force produced at the copper constantan interface is negligibly little in comparison to the electromagnetic force being monitored.
· Nickel Chromium Alloys
Compared to constantan and manganin, these alloys possess a slightly greater coefficient of thermal resistance. One illustration of this group of alloys is nichrome. Precision resistances cannot be made with these alloys. Nichrome resists corrosion also at extremely high temperatures as well as possessing high resistivity almost 50 times greater than copper. It is frequently employed in the more challenging resistors type, where a tiny size is crucial or high working temperatures apply. Certain alloys are challenging to solder, though.
· Gold Chromium
It is a recently developed alloy that seems quite promising for various uses. It contains slightly more than 2% chromium. At room temp, this alloy contains a resistivity that is around 20 times greater than coppers. By baking alloy at relatively low temperatures, its temperature coefficient may be reduced to an exceedingly minimal value. With copper, it possesses a thermoelectric Electromotive force of 8 or 7 V per °C. Gold chromium alloy is useful for various applications due to its exceptionally low-temperature coefficient, particularly for thermal-resistant criteria.
· Spools For Resistor Coils
In contrast to older wooden spools, metal spools or formers are now often utilized for high durable d.c. Resistors. The benefits of using metal spools include the following;
- Unlike hardwood formers, they don’t really collect air moisture. As a result, they don’t even fluctuate in size according to humidity or temperature. As a result, the resistance wire does not experience any fluctuating stresses that may otherwise modify the value of its resistance.
- The resistance wire’s current flow generates heat, which is easily dissipated by the metallic spools. This happens when the resistance wire comes in contact with the metal spool. The heat transfers to the metal spool, where it is then released to the environment by radiation and convection. As the spool’s outer surface is already subjected to the atmosphere, its whole surface, including its inside and outside. This effectively dissipates heat, preventing hot spots from developing inside the resistance wire.
- Most metallic spools are constructed of brass. This happens because there isn’t much of a difference in expansion between the spool and coil. Since brass does have a thermal expansion coefficient that is almost equivalent to the substances used in resistance coils. As a result, temperature fluctuations do not cause any noticeable alterations in resistance coils.
- Due to the loss of eddy current, they induce, using metallic spools in a.c. Applications are not only undesirable but also completely out of the question. The most common material for manufacturing a.c. The resistors’ spools are ceramic. Ceramic spools’ weak heat conductivity and substantially lower thermal resistance of linear thermal expansion than resistance wire are drawbacks of using them in high-precision resistors. As a result of differential expansion brought on by temperature fluctuations, strains are created in the coil windings.
· Resistance Wires
The resistance wire is often wrapped with cotton and silk or double silk. Before applying these coats, the wire is enameled.
Even though this necessitates using smaller cables than multilayered coils, high-standard resistors are coiled with just one coat of wire. Benefits of single-layered coil include:
- Single-layer wires provide more effective heat dissipation. On the contrary, the center layers of multi-layer wires are hotter.
- Coils with a single layer are more resilient. Multi-layer materials are less likely to adapt to changes in ambient humidity.
- Multi-layer coils typically exhibit a decrease in resistance stability over time.
Applications Of Resistors
Resistors are commonly useful in everyday electrical devices to control the amount of current that flows through them. It ensures that the devices work correctly. Nearly all electrical components encountered a resistor in them. Let’s take a look at some real-life instances of resistors.
1. Street Lighting
Streetlights turn on by themselves at night and turn off during the day because they have photoresistors. Photoresistors are sensors that can detect the level of light around them. When it’s dark, the resistance of the photoresistors changes, and this tells the circuit in the street lights to turn on. When it’s light outside, the resistance varies again, and the course turns off the lights. You can place photoresistors so they don’t confuse by shadows or car headlights. You can also use these sensors in cameras and burglar alarms.
2. Laptop and Mobile Chargers
Resistors are useful in laptops & mobile chargers to manage the flow of electricity and prevent overheating. The charger has different current readings, such as 2A, 1A, 500mA, or 700mA, which show how much electricity can pass through and how fast it will charge the device.
3. Temperature Control
By changing the resistance in a circuit, we can change its temperature. Joule’s Heating law explains this. It says the amount of heat a board produces depends on the current, resistance, and time. If we increase any of these factors, the heat will also increase. So, we can control the temperature in a circuit by adjusting the current, time & resistance values.
4. Fan Speed Controller
We can adjust the ceiling fan’s speed by turning a knob on the PCB. The knob has a connection to a particular resistor known as a potentiometer. So when we turn the knob, it changes the resistance and the amount of electricity flowing through it. It lets us control the fan speed utilizing the potentiometer.
5. Measuring Electrical Current
To measure current in a circuit, we can connect resistors of known resistance in a series. We use a particular resistor called a shunt resistor for this. Shunt resistors have high power/energy ratings & minimal resistance values. By measuring the voltage drop across the shunt resistor, we can calculate the current in a printed circuit board. One can do it by using Ohm’s law with voltage and current values.
6. Temperature Sensor
These sensors determine/calculate the hotness or coldness of non-living and living things. So thermistors are often useful in these sensors. You can use thermistors because they are sensitive to small changes in temperature. When the temperature changes, the impedance of the thermistor changes too. If the temperature is low, the resistance is low, and if the temperature is high, the resistance is also high. Temperature sensors measure this resistance and convert it into signals that provide readable temperature units like Fahrenheit and Celsius.
7. In-Circuit Functioning
In devices where we need to control the flow of electric current, like changing the pitch of a musical tone, adjusting the amplifier’s volume, or holding the speed of electric motors, we use variable resistors. These resistors let us change the current amount flowing through the device by rotating or sliding a knob that adjusts the resistance.
8. Heating Appliances and Lighting
Heating appliances such as heaters, kettles, electric ovens, and toasters have resistors. The resistors change the current into temperature/heat, which warms up the devices. The light bulb filaments utilized in these appliances also act like a resistor. It decreases the current and warms the filament wire until it produces light and heat.
9. LEDs & Transistors Protection
LEDs and Transistors are easily affectable by electric current. Too much current can damage their sensitive parts, while too little wind can affect their performance. To prevent this, you can link a fixed-value resistor in a series with the LED. These resistors only allow a specific current range to go through the device. These resistors are ballast resistors, and they protect LEDs from damage by limiting the current flow.
10. Timing Circuits
The resistors are useful in equipment that requires timing circuits, such as electronic sirens and light flashers. These timing circuit boards use resistors and capacitors or inductors, which store the energy from the voltage source. Capacitors slow down voltage change, while inductors slow down the electric current change. The time taken by the inductor and capacitor to charge depends on the resistance utilized in that board. If the resistance is high, it takes a long time to charge up, and if the resistance is low, it charges up quickly.
11. Lighting Circuits in Houses
In-home lighting systems and parallel resistive circuits are better than series circuits. If we link resistors/capacitors in the line, switching off a light bulb would switch off every bulb in the house. Also, in a series circuit, the current across all the loads is not the same. With more loads, the current per load decreases, and the load farthest from a source gets a nominal voltage. Thus, we use parallel resistive circuits where the voltage(current) across every load becomes similar, and turning off one bulb won’t switch off all bulbs because each bulb has its current/voltage source.
12. Blower Motor Resistor
It is a device that runs a fan to keep the air moving in a car’s ventilation system. To control the speed of the fan, use a blower resistor. The resistor is in series with the blower fan to regulate the electric current going through a motor. It usually has several resistors, and you can use it to adjust the fan’s speed by changing the resistance. You can use different designs to construct blower resistors, such as wound resistors placed in series or integrated circuits mounted on PCBs.
Frequently Asked Questions
What is the use of a resistor?
A resistor controls the flow of electrical current in an electronic circuit. It can also provide a specific voltage for energized equipment, like a transistor.
What are the four main types of resistors?
Types of Resistors
- Fixed Resistors.
- Linear Resistors.
- Non-Linear Resistors.
- Variable Resistor.
What are a resistor and unit?
Resistors are components that slow down the electricity flow in a circuit. Commonly you can find it in electronic circuits and electrical systems. You can calculate resistance in units called ohms.
Why are resistors essential?
Resistors create a voltage drop in electrical circuits, which helps ensure that components receive the correct amount of voltage. It can also protect members from sudden voltage spikes. Different elements in a board, such as lights or switches, require specific voltages to function correctly.
What is the resistor’s principle?
The resistor slows down the flow of electricity and reduces voltage by absorbing electrical energy. So in modern electronic circuits, this heat release is usually a tiny amount, less than one watt.
Are resistors AC or DC?
Resistors work in DC and AC circuits, while inductors only function in Direct Current circuits.
What are the two types of linear resistors?
There are two types of linear resistors: variable resistors and fixed resistors.
What are the main types of fixed resistors?
The primary kinds of fixed resistors include thin-film SMD resistors, wound resistors & carbon resistors.
What are the main types of variable resistors?
The primary forms of variable resistors are thermostats, potentiometers & trimmer resistors.
What is the use of resistors in the case circuits with LEDs?
When it comes to LEDs, the consequences of excess voltage can be dire since they are susceptible to changes in current. To prevent this, you can implement resistors to regulate the current that flows through the circuit.
By doing so, not only do they help avoid LEDs and other semiconductors from damage, but they also allow them to function within their optimal current ranges. LEDs are an essential component in various electronic devices, from simple household appliances to complex scientific instruments. Without proper current regulation, these devices would be susceptible to damage or failure. They are underscoring the vital importance of implementing resistors as a means of current control.
Conclusion
While we have discussed several vital parameters one may encounter while designing a board containing resistors, we cannot disregard others.
In most cases, a regular 1 percent metal film resistor with a power rating of 0.125 watts is sufficient for applications. However, certain products require a deeper understanding of a resistor’s specifications to ensure optimal performance. It is especially true for applications like power supply layouts, high-frequency layouts, audio work & products that operate in high ambient temperatures.
To achieve a highly reliable design and potentially prevent a time-consuming redesign, it is essential to meticulously examine the specifications and exercise great caution when selecting the appropriate resistor. By doing so, one can ensure that the resistor suits the application’s demands, thereby maximizing the effectiveness of the overall design.
