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Parallel DAC with High Voltage Output (+18V)

Hi can anyone recommend a parallel input DAC with high voltage output upto +18V useful for tuning of tunable filters from Hittite? If a parallel input-current out DAC is available for the purpose, how to convert it to voltage out without any offsets? I have with me AD5501 but it is a serial in DAC. I need parallel bits input.

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  • Thank you Mark and KenK for your suggestions. AD5546 may be the suitable part that I need but I have some doubts being a beginner in using DACs.

    1. What is meant by quadrant of a DAC?

    2. In my application most probably I need to use AD5546 in "Two-Quadrant Multiplying Mode Vout = 0 to +VREF" (Page 12 of datasheet). In Figure 20 for this mode, a +10 to -10V sinusoidal reference is given in R1A with an additional OPA2177 (U2A) connected between RCOMA and VREFA. Whereas in the equivalent circuit (Figure 19) to generate negative Vout "Two-Quadrant Multiplying Mode Vout = 0 to -VREF" just a positive 2.5V voltage reference ADR03 is used for all those pins. My doubt is why that extra opamp is required. Can we not use any -2.5V reference in this mode?

    3. What may be the best replacement for OPA2177 opamp that can safely operate upto +18V? The DAC output goes to varactor based tunable devices which tend to be very noise-sensitive. So a very low noise, high voltage opamp is required.

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  • Thank you Mark and KenK for your suggestions. AD5546 may be the suitable part that I need but I have some doubts being a beginner in using DACs.

    1. What is meant by quadrant of a DAC?

    2. In my application most probably I need to use AD5546 in "Two-Quadrant Multiplying Mode Vout = 0 to +VREF" (Page 12 of datasheet). In Figure 20 for this mode, a +10 to -10V sinusoidal reference is given in R1A with an additional OPA2177 (U2A) connected between RCOMA and VREFA. Whereas in the equivalent circuit (Figure 19) to generate negative Vout "Two-Quadrant Multiplying Mode Vout = 0 to -VREF" just a positive 2.5V voltage reference ADR03 is used for all those pins. My doubt is why that extra opamp is required. Can we not use any -2.5V reference in this mode?

    3. What may be the best replacement for OPA2177 opamp that can safely operate upto +18V? The DAC output goes to varactor based tunable devices which tend to be very noise-sensitive. So a very low noise, high voltage opamp is required.

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