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I'm struggling to understand what it means for a DAC to have a Multiplying Bandwidth of 200kHz. Does it mean that the max frequency component in the DAC's output cannot exceed 200kHz for reliable operation?

Context: My project is to build a special arbitrary waveform signal generator, and currently I am planning on feeding a Parallel interface DAC with digital data to generate signals.

Also the relevant datasheet describes multiple DACs, I plan on using AD5331 which has an unbuffered output (I guess that implies that they're not using an op amp at the DAC output) - if the definition of multiplying bandwidth only applies to DACs that contain amplifiers then would this spec be irrelevant to AD5331?

Following are relevant snippets from AD5331's (chosen DAC) datasheet: Multiplying Bandwidth spec

Datasheet definition of Multiplying Bandwidth

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I'm struggling to understand what it means for a DAC to have a Multiplying Bandwidth of 200kHz.

Normally, most people use DACs with a fixed DC voltage on the reference pin. However, some DACs allow you to superimpose an AC signal on the reference pin(s). This allows the DAC to perform the function of a digital/analogue multiplier. In effect, the digital word is multiplied by the reference voltage. So, you get a multiplier. It can also be called a digitally controlled attenuator. It can also be called a modulator.

Topologically, it's also the basis of all digital potentiometers.

Hence "Multiplying Bandwidth" refers to the signal on the reference pin. The 3 dB bandwidth is 200 kHz for this particular model.

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