Arbitrary waveform generator
Several TiePie engineering measuring instruments can be used as an arbitrary waveform generator (AWG). An AWG is an instrument that can generate repetitive or single shot signals. The signals can have a predefined standard shape like a sine wave or a square wave as in a conventional function generator. However, the signals can also have an arbitrary shape, defined by the user. These signals can be created using the Multi Channel software or an external program or can be signals previously measured by the oscilloscope and loaded in the generator.
TiePie engineering instruments that include an arbitrary waveform generator are the Handyscope HS5, Handyscope HS3 and the TiePieSCOPE HS805.
When to use an arbitrary waveform generator?
A waveform generator is an essential instrument in testing circuits. It can be used to apply a signal to a circuit under test, to test the functionality of that circuit.
A specific application of an arbitrary waveform generator is the ability produce signals that simulate certain external conditions without the need of having the actual condition. An example of this is generating a previously measured crankshaft sensor signal and apply that to the motor management system of a car. Various parts in the motor management system can then be tested without the engine having to run.
Also systems relying on serial communication signals can be tested this way.
Features of the Multi Channel software AWG
Generator screen. Click on the different areas to get more
information.
Display
The arbitrary waveform generator features a large display showing all properties of the generated signal, including a graph displaying the signal shape of the actual signal being generated.
Signal properties
The arbitrary waveform generator can generate several standard signal types: sine wave, square wave, triangular wave, DC and noise. Additionally, arbitrary signals can be generated. These can be previously measured signals, which can be loaded from a file or can be transferred directly from the measuring instrument. These can also be signals created in an external application.
A set of range select buttons and a slider are available to set the frequency of the arbitrary waveform generator. This can either be the signal frequency of the signal being generated or the sampling frequency at which rate the samples in the waveform buffer are being output. The minimum and maximum frequency will depend on the hardware instrument.
For the predefined periodical signals, a symmetry setting is available, to set the symmetry between 0 and 100%. A convenient speed button to set the symmetry to 50% is also available.
The amplitude of the generated signal can be set by means of a slider, controlling the full amplitude range of the amplitude.
An offset can be applied to the signal, a slider is used to control the size and the polarity of the offset. A speed button is available to set the offset to zero.
All signal properties can also be controlled by hot keys and entering the required value.
Output
The generator can be set to generate continuous signals or signals in burst mode. In burst mode, the number of cycles of the signal in the burst can be set. A burst can be started manually using the Start/Stop button or can be started by an external trigger signal (TTL).
The generator has three trigger output signals which can be used to trigger e.g. the oscilloscope:
| Trigger signal | function |
|---|---|
| Generator Start | is set when a signal or burst is started |
| Generator New Period | is set each time a new cycle of the signal is started |
| Generator Stop | is set when a signal or a burst is stopped |