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1. Can you give the THD Graph for AD9788?
2. Baseband Rate for 6MHz BW is 6.912MHz, DAC Clk = 6.912Mhz. With 8x interpolation, the frequency(Fout) will be 55.296MHz. What will be exact SFDR value at 55.296MHz?
3. Baseband Rate for 8MHz BW is 9.216MHz, DAC Clk = 9.216MHz. With 8x interpolation, the frequency(Fout) will be 73.728MHz. What will be exact SFDR value at 73.728MHz?
4. Do you have SFDR and THD measured for ATSC3.0 OFDM signal?
5. ACLR value is given for single carrier in AD9788 datasheet, can the ACLR values be given for multi-carrier modulation system like OFDM signal?
• HI,

Moved this thread to the High-Speed DACs community, where someone would be able to assist you better.

Best regards,

~ian

• Hi,

Can you give the THD Graph for AD9788?

We haven't concluded the evaluation for the THD for AD9788. The closest graph available is the In-band and Out-band SFDR graph. You may refer to Figure 39 and Figure 40 in Page 18 of the datasheet. The only difference is the THD considers the 2nd-to-5th harmonics, while the SFDR only concerns the highest non-fundamental spur.

• Baseband Rate for 6MHz BW is 6.912MHz, DAC Clk = 6.912Mhz. With 8x interpolation, the frequency(Fout) will be 55.296MHz. What will be exact SFDR value at 55.296MHz?
• Baseband Rate for 8MHz BW is 9.216MHz, DAC Clk = 9.216MHz. With 8x interpolation, the frequency(Fout) will be 73.728MHz. What will be exact SFDR value at 73.728MHz?

Can you confirm the frequency values you provided? The Interpolation factor should only concern your DAC Clk rate and your Data Rate, not the desired output frequency (Fout). You may refer to page 35 of the datasheet. If you mean that the Fout values are the DAC Clk rates, you can interpolate the SFDR values from Figure 39 and 40.

• Do you have SFDR and THD measured for ATSC3.0 OFDM signal?
• ACLR value is given for single carrier in AD9788 datasheet, can the ACLR values be given for multi-carrier modulation system like OFDM signal?

The output measurements and graphs are only measured with respect to a single wideband channel frequency (i.e. a single carrier frequency generated by the NCO). Also, THD, SFDR, and ACLR are measurements with single-tone inputs. You may procure an AD9788 evaluation kit (includes the eval-board and the controller board) if you wish to characterize the DAC based on your application.

Regards,

Marco