How to select an RF Attenuator
An RF Attenuator is an electronic device that reduces the amplitude or power of a high frequency signal with minimal distortion. Attenuators are used for a number of applications, the most common being to reduce the amplitude of an incoming signal, which may be too high to process a system.
Type’s of RF Attenuators:
Fixed Attenuators: These have a fixed attenuation value for a set frequency range.
Variable Attenuators: The attenuation can be changed by varying the voltage or current to the device. These are used in applications where the signal level is fluctuates.
Step Attenuators: The attenuation can be modified in fixed steps. These have many applications especially in test labs where different attenuation levels are required for testing different circuits.
Programmable Attenuators: These are programmed to provide a certain level of attenuation.
Key Parapemters
Frequency (MHz): This is the frequency range over which the device can operate with while providing a constant level of attenuation with minimal reflections.
Attenuation (dB): This is the ratio of the output and input power levels.
Power (W): The power that the attenuator can handle while maintaining the integrity of the signal i.e the Attenuation level with minimal reflections.
Impedance (Ohms): The impedance must match the circuit/system it is connected to; this will minimize any reflection within the circuit/system. Usually the impedance is 50 Ohms or 75 Ohms.
Package Type: Various Package options are available – Connectorized, Modules, Surface Mount, Waveguide, Die etc.
Other Parameters: There are a number of other parameters that are relevant when searching for attenuators, these are: oltage, Bits, Directionality etc.