Hi! I have problem iwth using ltc2000-16. SFDR = 47dBc(fout = 270MHZ, fdac=1200MHz) Rfsadj = 500Ω, Rload = 12,5Ω, LIN_DIS = 0, LIN_ GN = 75%, power is fine. What's the matter?
It looks like the 2nd is elevated. What are you using to do the differential to single ended translation to drive the spectrum analyzer? Can you post a picture of your setup? What clock are you using?
Hi! We are using TC1-1-13MA+ to do the differential to single ended.
Other registers by default.
For the DAC clock using LMX2582. oscillator 156,25MHz +/- 20 ppm Best regards, Gleb.
>reply from Clarence.Mayott in High-Speed DACs - View the full discussion
Only a single transformer? The TC1-1-13MA+ has an asymmetric construction so it isn't the best for 2nd. We typically use that transformer with a second transformer to restore the balance and improve the symmetry. Check out the DC2233:
DC2233A Evaluation Board | Analog Devices
We use the TC1-1-13 and an additional transformer to get better symmetry, better balance and better 2nd harmonic distortion.
Can you send a picture of your setup and schematic and layout there might be other issues as well.