MELF resistors, or Metal Electrode Leadless Face resistors, are specialised electrical passive components designed to provide a better performance, long-term stability, reliability and moisture resistance in the modern-day soldering processes. They are comparatively more expensive and are widely used in specific applications where a higher level of performance is a necessity.
Basics of MELF resistors
The basic characteristics of MELF are:
These components have a cylindrical shape and have metals at each end.
They are made of a high-grade ceramic body of 85% alumina and have a coating of a homogeneous film of metal alloy.
The metal ends of the cylindrical rod of the MELF have nickel-plated steel caps.
The outside coating of the component acts as a protective covering and offers protection from different environmental conditions.
The MELF comes in a variety of sizes which include: MELF (MMB) 0207 L: 5.8 mm, Ø: 2.2 mm 1.0 W, 500 V; MiniMELF (MMA) 0204 L: 3.6 mm, Ø: 1.4 mm 0.25 W, 200 Vb and MicroMELF (MMU) 0102 L: 2.2 mm, Ø: 1.1 mm 0.2 W, 100 V.
MELF resistors have a very specific range of applications, particularly due to their extensive advantages. These include:
A high level of reliability.
A better capability to enable predictable pulse handling.
A higher tolerance of 0.1% while manufacturing.
A lower temperature coefficient while manufacturing.