Arbitrary Waveform Generators vs. Function Generators

When it comes to electronic test instruments, waveform generators are essential tools for engineers and researchers alike. They allow for the generation of electrical waveforms that are crucial for testing, troubleshooting, and development across a wide range of applications.

Two common types of waveform generators are Arbitrary Waveform Generators (AWGs) and Function Generators. While they share some similarities, they serve different purposes and have distinct capabilities. So, what is the difference between an arbitrary waveform generator and a function generator?

Closeup of screen and buttons on a 50 MHz Arbitrary Waveform Generator
AWG, courtesy of Wikimedia Commons

Waveform Generation Capabilities

A function generator, such as the Keysight 3310A, is a versatile tool known for its simplicity and ease of use. Its primary function is to generate basic waveforms such as sine waves, square waves, triangle waves, and sawtooth waves. Engineers and hobbyists often use function generators to produce predefined waveforms at various frequencies, amplitudes, and duty cycles. These instruments are valuable for basic signal testing, audio testing, and educational purposes.

On the other hand, an Arbitrary Waveform Generator (AWG) like the Keysight M9330A offers a higher level of waveform generation flexibility. While it can also generate basic waveforms, its true power lies in its ability to produce custom, user-defined waveforms. AWGs enable users to create waveforms by specifying discrete data points, allowing for the generation of virtually any waveform within the instrument’s bandwidth and memory limitations. This versatility makes AWGs suitable for a broader range of applications, including RF signal generation, advanced waveform synthesis, and precise control in research and development.

Waveform Flexibility

Function generators are limited to producing basic waveforms with adjustable parameters like frequency and amplitude. They are excellent for scenarios where standard waveforms suffice but lack the flexibility to create complex custom waveforms.

In contrast, AWGs offer more flexibility. Users can program these instruments with specific voltage levels at precise time intervals, allowing for the creation of custom waveforms tailored to the application’s requirements. This flexibility is especially valuable in applications that demand precise control over waveform shape and timing.

Closeup of Engineer Testing Sound System

Applications

Function generators find their niche in simpler applications, such as audio testing, analog circuit testing, and basic signal generation for educational purposes. They are well-suited for scenarios where basic waveforms suffice.

AWGs, with their advanced waveform generation capabilities, are suitable for a broader range of applications. These include RF signal generation, digital signal processing (DSP) testing, radar and communications testing, and any scenario that requires precise control over waveform shape and timing.

Complexity and Cost

Function generators are typically less complex and less expensive than AWGs due to their limited waveform generation capabilities. They are a cost-effective solution for basic waveform generation needs.

AWGs are more complex and usually more expensive. This is primarily because of their ability to generate custom, user-defined waveforms, making them indispensable for advanced applications.

While both Arbitrary Waveform Generators and Function Generators are valuable tools in the world of electronic testing and development, they cater to different needs. Function generators are simpler and excel at generating basic waveforms, while AWGs offer greater flexibility, making them ideal for applications requiring precise control and complex waveform generation. The decision between the two will be based on your project’s particular needs and the degree of waveform customization required.