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I'm working on a project requiring production of sinusoidal waves. Normally, from my understanding, a DAC can produce a waveform that alternates between a negative voltage and a positive voltage, but for my needs I need the DAC to produce a waveform that alternates between a zero voltage and a positive voltage.

Is this possible using a DAC, and if not how would I produce such a waveform?

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  • \$\begingroup\$ It depends on DAC. There are many kinds of DACs. Select one with only positive output. \$\endgroup\$
    – Justme
    Jul 10, 2020 at 15:30
  • \$\begingroup\$ Choose your DAC - most do what you want. \$\endgroup\$
    – Andy aka
    Jul 10, 2020 at 16:37
  • \$\begingroup\$ Many, if not most, are positive only but bi-polar ones exist, especially for audio. \$\endgroup\$
    – winny
    Jul 10, 2020 at 22:04
  • \$\begingroup\$ Digikey lists about 13000 DACs. \$\endgroup\$
    – Russell McMahon
    Jul 11, 2020 at 5:20
  • \$\begingroup\$ Of these VERY ROUGHLY about 1600 have bipolar supplies, and the balance have unipolar outputs. \$\endgroup\$
    – Russell McMahon
    Jul 11, 2020 at 5:20

1 Answer 1

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DACs are conventionally single polarity and made bipolar with an Op Amp and bipolar supply.

Digikey has about 10% of its unique p/n's for DAC in bipolar (771 of 7441 , others are duplicates but currently stock only 335 of 2,472) That should be enough to choose from ;)

To appease others who might want to make a bipolar DAC. Falstad Sim Proof

Offset -5V from Vref =+5V of DAC . (Or any Vref used by DAC for lower supplies.

Gain =2 to generate +/-5V using a 0~5V sawtooth sweep and CMOS RRIO Op AMP using +/-5V supplies.

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  • \$\begingroup\$ Comments are not for extended discussion; this conversation has been moved to chat. \$\endgroup\$
    – Russell McMahon
    Jul 12, 2020 at 12:24

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