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I previously had a question on using AC reference voltage with a MDAC, But it has been addressed nicely in the answer below.

How does the "Multiplying Bandwidth" specification relate to a DAC output's maximum bandwidth

But how would the fluctuating reference voltage not impact the output value, considering that a precise DC Vref is not required?

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The MDAC reference does impact the output voltage.

The nominal output is the reference voltage vref(t) multiplied by the digital input Code/2^N in the case of a voltage output MDAC (or some scale factor different).

All DACs with a reference voltage input are multiplying DACs in a sense, but MDACs are designed to allow the reference voltage to vary over a wide range and typically are characterized for the reference voltage changing relatively quickly with respect to time.

In the case of a 4-quadrant MDAC the reference can be negative or positive with respect to ground and the code can also be positive or negative.

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  • \$\begingroup\$ Thank you! Any application references where we can use AC reference voltages for MDAC's? \$\endgroup\$
    – Chetan Karkera
    Commented May 11 at 9:38
  • \$\begingroup\$ See DAC datasheets such as AD78x7 where they list guaranteed characteristics with AC references, in that case 100mVp-p (small signal BW), 20Vp-p (full power BW), 6V RMS (THD). \$\endgroup\$
    – Spehro 'speff' Pefhany
    Commented May 11 at 13:13

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