Introduction to the SIG852 arbitrary waveform generator based on computer software (similar to a virtual oscilloscope)

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Introduction to the SIG852 arbitrary waveform generator based on computer software (similar to a virtual oscilloscope) [Copy link]

For hardware engineers engaged in circuit board development, signal sources are frequently used and very familiar. We use them as inputs to circuit boards to test whether the circuit boards can process these signals normally as expected. The simplest example is an amplifier circuit. We will input a sine wave into it, and then use an oscilloscope to observe the input and output waveforms to see whether the sine wave is amplified, whether there is distortion, etc., so that we can know whether the amplifier circuit board we made is successful.

The most widely used signal sources are regular periodic waveforms, such as sine waves, triangle waves, and square waves. It is relatively easy for us to obtain these signals. There are many products and related materials, so we will not go into details here. Engineers with much engineering experience will definitely feel that sometimes in projects or when testing circuits, some strange signal waveforms are needed, which are not periodic or even irregular special waveforms. At this time, ordinary signal sources cannot do it. At this time, an arbitrary waveform generator ( AWG) is needed.

Arbitrary waveform generator ( AWG) can be edited to generate any special waveform signal to achieve signal input in various scenarios.

For example, simulate various automotive sensor signals such as pressure, temperature, speed, rotation and angular position to perform functional testing and optimization of engine control units (ECUs) in automotive applications. Simulate crankshaft, camshaft, wheel, collision and other automotive engine sensor signals. For example, use pulse signals to simulate power MOSFET circuits to test startup and shutdown delays and rise and fall times. Analyze the switching waveforms of IGBT circuits. For example, simulate normal and irregular biomedical signals (such as cardiac fibrillation) to perform functional testing of medical devices. For example, simulate two servo valves to determine the startup time (step response), frequency response (Bode curve) and other indicators in the product technical data.

For low-frequency applications below a few kHz, the LOTO virtual oscilloscope team has launched an AWG arbitrary waveform generator product based on PC host software, model SIG852, which is a very cost-effective arbitrary waveform generator. As long as there is a computer and a mouse is used to edit and draw, arbitrary waveforms can be quickly generated.

From the above figure, we can see that LOTO's SIG852 arbitrary waveform generator can generate some conventional waveforms, such as sine wave, triangle wave, square wave. Let's mainly look at its built-in unconventional special waveforms:

White Noise:

Sinx/x:

Exponential Rise (Charging):

Gaussian pulse:

The advantage of computer software operation is that you can use the mouse to draw a waveform directly, as shown in the following figure:

This is very convenient. Sometimes engineers know the general appearance of a waveform, but it may be difficult to describe it in words. In the past, they could draw it on paper to explain it, but it was very difficult to actually output such a waveform. Now with such computer host software, they can draw it directly with the mouse, and what they see is what they get.

The drawn waveform can be further edited, and the local voltage can be set to any voltage, and noise can also be superimposed:

You can also perform mathematical operations on the four waveforms you selected, such as Y = A*X1+B*X2+C*X3+D*X4+E,

You can also edit and map the waveform in segments, as shown below:

For the price of two or three hundred yuan, SIG852 is still very cost-effective. Due to cost control, the hardware performance is limited. There are two channel outputs, a total of 4000 points of data can be edited, and it can be output in a loop or single time. The sampling rate of the signal output is up to 70K, so it is recommended that the frequency of the waveform is up to a few K, which is ideal. The important thing is that there is still a lot of room for development in the software, and it will continue to be added for free.