0
\$\begingroup\$

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?

\$\endgroup\$
5
  • \$\begingroup\$ It depends on DAC. There are many kinds of DACs. Select one with only positive output. \$\endgroup\$ – Justme Jul 10 '20 at 15:30
  • \$\begingroup\$ Choose your DAC - most do what you want. \$\endgroup\$ – Andy aka Jul 10 '20 at 16:37
  • \$\begingroup\$ Many, if not most, are positive only but bi-polar ones exist, especially for audio. \$\endgroup\$ – winny Jul 10 '20 at 22:04
  • \$\begingroup\$ Digikey lists about 13000 DACs. \$\endgroup\$ – Russell McMahon Jul 11 '20 at 5:20
  • \$\begingroup\$ Of these VERY ROUGHLY about 1600 have bipolar supplies, and the balance have unipolar outputs. \$\endgroup\$ – Russell McMahon Jul 11 '20 at 5:20
4
\$\begingroup\$

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.

\$\endgroup\$
1
  • \$\begingroup\$ Comments are not for extended discussion; this conversation has been moved to chat. \$\endgroup\$ – Russell McMahon Jul 12 '20 at 12:24

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.