RF attenuators act as resistors and are used to reduce the level of a signal within radio frequency applications and RF circuits. They have many benefits, including protecting a circuit stage from receiving a current that's too high. RF attenuators can also improve impedance match, ensuring power transfer from source to load is optimised.

Types of RF attenuators

RF attenuators come in three types:

Fixed RF attenuators provide an unchanging value where specific attenuation levels are needed.
Switched RF attenuators are made up of switches that allow varying levels of attenuation.
Variable RF attenuators are used when it's necessary to continuously change the level of a signal.

Choosing the right RF attenuators

To select the right RF attenuator a number of specifications need to be considered, such as attenuation, frequency and impedance. Attenuation is measured in decibels (dB) and depending on the type of attenuation you need this will either be fixed or within a range. RF attenuators are designed for devices with a certain impedance and it's important to match the impedance of the attenuator to the circuit where it will be used.