DAC38RF89: How to output Iout and Qout at the same time?

Jim,

     I think that wideband DUC mode can output Iout or Qout only, not output Iout adn Qout at the same time.

User,

My answer was slightly incorrect. In the wideband DUC mode, the data that would normally go to DAC B is sent to the output summer of CHA, and both outputs are summed to provide a complex output at CHA. See attached. The device can bypass the channel mixers and send the data directly to the DAC's. In this case you could send I and Q data at the same time to both DAC's. This is how the device works in real data mode with no interpolation or NCO. 

Regards,

Jim

DAC38RF8x Wideband Mode.pptx   

Jim,

I mean that In real data mode, I want to output Iin*cos(2π*fnco)-Qin*sin(2π*fnco) and Iin*sin(2π*fnco)+Qin*cos(2π*fnco) at the same time.

How to do it?

Regards,

John

John,

I am still confused by your request.

1. Are you using real or complex input data?

2. Do you want real or complex output data?

3. Do you plan on using the NCO?

4. Do you plan on using both DAC outputs? If you only plan on using one DAC output, are you trying to get both I and Q data summed together on this one output? 

Regards,

Jim

Jim,

1. Are you using real or complex input data?-------Complex input data. But I config DAC38RF89 work in real mode,because input data rate is 2.5GSPS.PathAB of DACA for I-channel,and pathAB of DACB for Q-channel.

2. Do you want real or complex output data?-------I want compelx output data.

3. Do you plan on using the NCO?-------Yes, I use NCO.

4. Do you plan on using both DAC outputs? If you only plan on using one DAC output, are you trying to get both I and Q data summed together on this one output? -------I want to use both DAC outputs. DACA output Iin*cos(2π*fnco)-Qin*sin(2π*fnco), and DACB output Iin*sin(2π*fnco)+Qin*cos(2π*fnco). Can this be achieved？

Regards,

John

Jim,

How to config the DAC38RF89?

The input data rate is 2.5GSPS,and use 2x interpolation.

If use pathCD, I think Jesd format is only available in the red box of Table 9. But in these cases, the max input data rate is only 625M.

When jesd format uses 82121 mode, the max input data rate up to 2.5G, but the pathCD can not  be used.

In the DAC38RF89 EVM tool, when congfig to real input mode, the Mixer and NCO of pathCD can not be enabled.

Jim,

Is there a solution to this problem?

Regards,

John