Rita, Your schematic looks fine. Make sure sleep is low and TXENABLE is high to get an output. I do not see what is driving SYSREF and DACCLK but make sure the DACCLK is AC coupled and at the proper voltage swing. If SYSREF is DC coupled, make sure this is at the proper common mode and swing per the data sheet. To verify that SYSREF is being captured properly, you can run a test only using the NCO. Setup the DAC per the attached file so that the NCO is enabled with the DAC in constant input mode. Have the NCO sync source be set to SYSREF. If the NCO frequency is not integer multiple of the SYSREF frequency, the DAC output will appear as many tones if SYSREF is being captured properly. If it is not being captured properly, the output will be a single tone at the NCO frequency. Regards, Jim (Please visit the site to view this file)
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