A function generator is an electrical testing device that produces electronic signal patterns, both repeating and nonrepeating. The signal pattern is formed with varying frequencies and amplitudes, and its graphical representation is called a waveform. A waveform represents the increase and decrease of voltage over a span of time. Function generators commonly produce sine waves, square waves, triangular waves, and sawtooth waves.
Function generators are commonly used in the development and testing of electronic equipment. The waveform signals are used to trigger responses in a circuit or electronic device in order to test the system or diagnose problems. Controls adjust the parameters of the signal that create the waveform, such as frequency and amplitude. Each function generator works within a specified frequency range, such as 0.2 Hz to 200 KHz or up to 15 MHz, and may output voltage in one or more amplitude ranges. A screen on the front of the unit displays the waveform and its parameters.
Specialized function generators can produce diverse waveforms and are used for testing electronic devices and providing stimulus signals to circuits or systems. One type known as an arbitrary/function generator (AFG) can produce familiar waveform shapes such as sine, square, triangle, sweep, pulse, ramp, modulation, and haversine. It can also generate variations on the waveforms and switch between frequencies quickly. For applications that require greater versatility of waveform signals, an arbitrary waveform generator (AWG) can produce waveforms of any shape.
A function generator integrated circuit, sometimes called a function generator IC, is a microchip that can produce signals such as sine, square, triangle, ramp, and pulse waveforms. It can be integrated into other devices to manage processes or control device operations.
Considerations when choosing a function generator include frequency range, voltage output range, and the required waveform signals. Manufacturers include Rigol and Tektronix.