A Buyer's Guide to Resistor
The operations of countless modern electronic devices and systems hinge on the ability to properly manage current flowing throughout individual circuits, a major element that plays a role in this being the resistor. As a simple yet fundamental element of electrical design, it is crucial that one has a basic understanding of resistors and their importance. In this blog, we will provide an introduction to these building blocks of electrical circuits, covering their functionality, common types, and important features to look out for during procurement.
What are Resistors and How Do They Work?
In the realm of electronics, resistors are a form of passive electronic component that is able to impede the flow of electric current. This is achieved through the properties of the materials they are made from, where resistance determines the ability of electricity to flow through the component. With their resistance levels measured in ohms (Ω), these components are typically used to enact voltage division, current limiting, and signal conditioning within electronic circuits.
Common Types of Resistors
Wire-Wound Resistors
Constructed by winding a resistive wire around a ceramic or fiberglass core, wire-wound resistors are known for providing high power ratings and reliable precision. As a result, they are popular in power supplies, motor control circuits, and other high-power applications.
Metal Film Resistors
With a metal film resistor, a thin film of metal alloy is deposited onto a ceramic substrate to impede flow. With this construction, metal film resistors offer a good level of stability and low temperature coefficients, driving their use within precision circuits, audio equipment, and various forms of instrumentation.
Carbon Film Resistors
With these resistors, a thin film of carbon is deposited onto a ceramic rod, presenting a cost-effective yet reliable option for many general-purpose applications. For example, one will most commonly find these components within consumer electronics and hobbyist projects, as compared to advanced machinery.
Metal Oxide Resistors
By depositing a metal oxide onto a ceramic substrate, the resulting resistor is able to provide high levels of stability and low noise characteristics. As a result, metal oxide resistors are very suitable for precision circuits and other high-frequency systems.
Thermistors
Thermistors are a form of temperature-sensitive resistor, meaning that their level of resistance adjusts in accordance with temperature fluctuations. This allows them to excel in temperature sensing and control applications, a recognizable use being within thermostats and temperature compensation circuits.
Thin-Film Resistors
Following thin-film deposition techniques, thin-film resistors are able to achieve high levels of stability and precision, driving their use within amplifiers, medical devices, and other applications that require tight tolerances.
Important Attributes of Resistors to Keep in Mind
When it comes time to begin shopping for resistors, there are a number of attributes that are important to keep in mind, each having a major effect on compatibility and performance.
Temperature Coefficient
The temperature coefficient of a resistor serves to indicate how much resistance will change as temperatures vary, where a lower the coefficient, the more stable the resistor will be across a wide range of temperatures.
Resistor Ageing and Stability
Resistor aging and stability determine how resistance and durability may be affected over time, so always be sure to look out for options that provide the protections your project calls for.
Thermal and Power Rating
The thermal and power rating of a resistor specifies the maximum amount of power that it can dissipate without overheating. It is essential to select a resistor with an adequate power rating for the intended application, lest it run into performance or safety issues.
Resistor Noise
Resistor noise is the unwanted byproduct generated by the resistor as it dissipates heat, with some materials and options being very quiet for the benefit of audio amplifiers and instrumentation.
High-Frequency Behavior
This behavior describes a resistor’s performance at high frequencies, with some exhibiting parasitic inductance or capacitance that can affect their performance at higher levels.
Aerospace Store: Your Source for Quality Resistors
Here at Aerospace Store, we can connect you with quality assured resistors that have been sourced from leading manufacturers and suppliers across the globe. We offer access to a wide range of electronics and electro mechanicals to meet the diverse needs of our customers, as well as the benefit of timely fulfillment and competitive pricing. When you are ready to make a purchase on our website, fill out and submit a Request for Quote (RFQ) form on our website, knowing our staff will be in touch shortly to provide tailored fulfillment options for your comparisons.