What is the advantage of a metal film resistor compared to carbon-composition resistors?

A metal film resistor has several advantages over carbon-composition resistors, one of which includes being less affected by aging. This is significant because metal film resistors tend to have a more stable resistance value over time. Carbon-composition resistors can degrade due to environmental factors such as humidity, temperature, and physical stress, leading to an increase in resistance or variance from their original specifications.

In contrast, the construction of metal film resistors incorporates a thin film of metal on an insulating surface, which provides greater consistency and reliability. This stability means that metal film resistors maintain their performance characteristics longer, making them a better choice for precision applications where long-term reliability is crucial. Additionally, their lower noise and temperature coefficient properties further enhance their performance over time, solidifying their reputation for durability in electronic circuits.

By using metal film resistors, designers can achieve more reliable circuit performance and reduce the likelihood of component failures due to aging effects.