“Film Resistor” is a generic term consisting of Metal Film Resistor, Carbon Film and Metal Oxide Film resistor types. These types of resistors are normally made by depositing a pure metal, like nickel onto an insulated ceramic rod. An oxide film, like tin-oxide can sometimes be substituted for a pure metal.
Film resistors can be called “thick film” resistors by increasing the thickness of the deposited film. Also decreasing the amount of film will create a “thin film” resistor. Adding or decreasing the film will in turn control the resistive value of the resistor. A laser is then used to etch a high precision spiral groove into the film. The groove effects the film by creating a conductive or resistive path around the resistor some what like a coil.
This specific way of manufacturing allows for a more precise tolerance. It can be as low as 1% or lower. This method is much more effective than carbon composition types. Much higher ohmic values can be achieved by film type resistors compared to other resistors.
Metal Film Resistor
A typical kind of axial resistor today is described as a metal film resistor. Steel electrode leadless face (MELF) resistors commonly use the very same technology, but are a cylindrically shaped resistor designed for area positioning. Take note that additional types of resistors (e.g., carbon composition) are also offered in MELF bundles.
Steel film resistors are generally covered with nickel chromium (NiCr), however could be covered with any of the cermet materials detailed above for thin metal resistors. Unlike slim film resistors, the component might be applied making use of various methods compared to sputtering (though that is one such technique). Even, unlike thin-film resistors, the resistance worth is figured out by cutting a helix through the layer as opposed to by etching. (This resembles the method carbon resistors are made.) The outcome is an affordable resistance (0.5 %, 1 %, or 2 %) as well as a temp coefficient that is usually between FIFTY as well as A HUNDRED ppm/K. A Metal film resistor has really good noise features and inexpensive non-linearity due to a reasonable current coefficient. Helpful are the parts reliable resistance, temperature coefficient and durability.
Metal Oxide Film
Metal-oxide film resistors are constructed from steel oxides such as tin oxide. This outcomes in a higher operating temp and also greater stability/reliability than Steel film. They are made use of in applications with high endurance demands.
Visit our Facebook Page - Electrical-info FB page