questions about the output of DAC3152EVM?

Hi Ouyang,

I'm not quite sure what you're asking... The output of the DAC3152 will be an analog signal. The shape of the signal will depend on the digital pattern that you load into the TSW1400. You should be able to look at this signal on an oscilloscope. It may look a little weird if you do not low pass the filter because the DAC output is a zero-order hold function. Such that a sine wave may look like it has steps in it.

Those resistors would be used to bypass the output transformer. This could be used instead of the transformer to get a differential output signal.

Regards,
Matt Guibord 

Hi,Matt Guibord 

    Thanks  you very much.

      First ,in the DAC31X2EVM the resistors R211, R207, R191, and R195 don't install so the singal can not  send to TRF3703 ,So I think we can not realize Signal modulation function if we don't install these resistors,but in the DAC31X2 EVM user's Guide ,it talk about the "DAC31x2EVM Configuration for Modulator Output" it doesn't talk about install these resistors,I don't know why?

     The second question is in the DAC31X2 EVM user's Guide ,it talk about "DAC31x2EVM Configuration for DAC Output" that we shoud remove  the resistors R109, R110, R111, and R112,and install he resistors R211, R207, R191, and R195 ,then we can use the Spectrum Analyzer at the two DAC outputs of theDAC31x2EVM (J3 and J2),but in the file "TSW140x High Speed Data Capture/Pattern Generator Card" user's guide said that  the example of "Testing with DAC3152 EVM"don't tell us to install someresistors or remove some resistors we can aslo  use the Spectrum Analyzer at the two DAC outputs of theDAC31x2EVM (J3 and J2).I don't know why is it.

Regards,
ouyangzhao,ouyang

Hi Ouyang,

I apologize, there is a typo in the user's guide. The step below should be applied to section 2.4 and worded as:

Step 1. Four 0-Ω resistors must be moved in order to configure the output of the DAC31x2 as the TRF3705 I/Q modulator
• Remove the resistors R109, R110, R111, and R112
• Install the resistors R211, R207, R191, and R195

And step 1 of section 2.5 should be disregarded. The board is initially setup for the IF outputs through the transformers. Take a look at the schematic on the DAC3152EVM product folder to see the default configuration.

Regards,
Matt Guibord 

Hi Matt Guibord ,

  Thanks for you reply.so the questions have get answers ,thank you agian ,best wish to you.

Regards,
ouyangzhao,ouyang

Hi,Matt Guibord
           Thanks for you reply.

     I have a question that If the the TSW file storage is a single-channel data, then what would A, B channel output data will be?Will it make data of one channel divided into two channels to output,if it works in this way we can not see the original signal by the output channel A or B?

Regards,
OuyangZhao,ouyang

Ouyang,

The csv file should be organized into columns, such that column A is sent to DAC A and column B is sent to DAC B. If a single column is loaded, there should be no output on DAC B.

Regards,
Matt Guibord

Hi, Matt Guibord

    Thanks for you help,and best wish to you.

 Regards,

OuyangZhao,Ouyang