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Here's a simplified basic example of a programmable Arbitrary Waveform Generator. (Simetimes called an ARB). Hopefully, it will help anyone better understand how they work. I've pre-loaded a sine wave amplitude data as the default example. (Blue waveform).
Here are some other waveforms you can try yourself. Just enter the data on the logic buttons.
Square Sawtooth AM
000 000 100
000 001 011
000 010 101
000 011 010
111 100 110
111 101 010
111 110 101
111 111 011
An AWG is a device that can produce any type of periodic signal. It can make sine, square, triangle, sawtooth, AM, FM, or any other predefined shape. It does this by storing the entire waveform as a series of binary numbers in memory. Then, it goes through the stored information and sends it one at a time to a digital to analog converter (DAC). This will convert the digital point stored in memory to an analog voltage output.
The number of points or samples of signal data that an AWG can store is called memory depth. Mine has only 8 samples (for a total of 3 bytes of waveform memory), but real ones have Giga samples of storage space.
The rate at which these samples can be sent to the DAC is called the sample rate. Mine is directly controlled by the clocks, which is 1 Ks/s.
The resolution of an AWG is how much detail the DAC has in bits. Mine is 3 bits for an analog range of 8 voltage levels. In practice, this can be limited by factors such as noise, leading to less effective resolution (or effective number of bits, ENOB).
This example does NOT use DDS (Direct Digital Synthesis). DDS is a clever way to adjust the frequency of the output without changing the sample rate or clock frequency. (Notice how the frequency of mine is unadjustable and stuck at the clocks frequency...) DDS calculates the next phase angle based on the desired frequency and uses that to determine which point in memory to access next.
Upgrade circuit here: https://everycircuit.com/circuit/6141640988950528
Frequency Variable https://everycircuit.com/circuit/5404744524496896
DDS https://everycircuit.com/circuit/6214446053326848
NCO: https://everycircuit.com/circuit/5760185112723456
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