Resistors Definition

JMBom is a go-to place for resistors and has a huge selection. They carry everything from Carbon Composition and Ceramic Composition Resistors to various Chassis Mount types like Planar and Wirewound. You can also find Current Sense Resistors in SMD and Through Hole versions. For Film Resistors, they offer Metal Film (Through Hole), Planar (Chassis Mount), Thick Film (both SMD and Through Hole), and Thin Film (SMD).

They also have High Frequency/RF Resistors, MELF Resistors, and Metal Foil Resistors (SMD). You’ll find Metal Oxide Resistors, Potentiometers, Precision Potentiometers, Resistor Kits, Networks & Arrays, and Slide Potentiometers.

In the SMD category, they stock Chip Resistors for Current Sensing, High Frequency/RF, Metal Foil, Thick Film, and Thin Film. For Through Hole options, they have Carbon Composition and Ceramic Composition Resistors. They also offer Trimmer Resistors in both SMD and Through Hole varieties, along with Variable Resistors and Wirewound resistors (Chassis Mount & Through Hole).

About Manufacturers

There are lots of resistor manufacturers out there like Yageo, Bourns, KOA, NIC, Samsung, Viking, Vishay, VPG, TT, Stackpole, and many more. You can easily find resistors by brand using the brand filtered search option.

Frequently Asked Question

What is resistance?

Resistance is how much something opposes the flow of electric current in a circuit. It’s measured in ohms, shown as the Greek letter omega (Ω). Everything resists current to some extent, and materials are usually classified as either conductors or insulators. Conductors, like silver, copper, gold, and aluminum, have very low resistance, allowing current to flow easily. On the other hand, insulators like rubber, paper, glass, wood, and plastic have high resistance, making it hard for current to pass through them.

What do resistors do?

Resistors serve many purposes. They can limit electric current, divide voltage, generate heat, match and load circuits, control gain, and set time constants. You can find resistors with a huge range of resistance values, spanning over nine orders of magnitude. They’re used in countless applications, from tiny surface-mount devices in electronics to large dynamic braking resistors that help dissipate energy.

What are the two types of resistors?

Resistors fall into two categories: fixed and variable. Fixed resistors have a constant resistance, set during manufacturing, and the value is either printed or color-coded on them. Variable resistors, on the other hand, can have their resistance adjusted by turning a knob. While they’re less common due to their moving parts and the resulting uncertainty, they’re still useful in certain situations.

What causes a resistor to fail?

A fixed resistor usually fails in an open state when it gets too hot or is overstressed by too much power, high temperatures, vibration, or shock. Too much humidity can also increase its resistance. As for variable resistors, they can wear out after too much use, with worn particles sometimes causing high resistance short circuits.