Vishay SMM02040D3123BB300

The resistance-change factor per degree Celsius of temperature change is called the temperature coefficient of resistance. This factor is represented by the Greek lower-case letter “alpha” (α). A positive coefficient for a material means that its resistance increases with an increase in temperature.

Resistance is a fundamental property of electronic components that measures their opposition to the flow of electric current. It is denoted by the symbol "R" and is measured in ohms (Ω). Resistance is caused by the collisions of electrons with atoms in a material, which generates heat and reduces the flow of current. Components with higher resistance will impede the flow of current more than those with lower resistance. Resistance plays a crucial role in determining the behavior and functionality of electronic circuits, such as limiting current flow, voltage division, and controlling power dissipation.

Lead Free is a term used to describe electronic components that do not contain lead as part of their composition. Lead is a toxic material that can have harmful effects on human health and the environment, so the electronics industry has been moving towards lead-free components to reduce these risks. Lead-free components are typically made using alternative materials such as silver, copper, and tin. Manufacturers must comply with regulations such as the Restriction of Hazardous Substances (RoHS) directive to ensure that their products are lead-free and environmentally friendly.