DAC38RF82EVM: In the following Settings, why the output signal quality is poor and the time domain waveform is not visible at all

Xiaodie,

Did you run "PLL Auto Tune" and verify the DAC PLL is locked? Is the shunt on JP10 removed? Are you providing a 562.5MHz clock @ 12dB to SMA J4, LMK CLKIN? My setup has no issues with this settings.

It also appears like you did not select the DAC38RF8x_LMF_841 ini file in HSDC Pro.

Regards,

Jim

JIm，

1, I am sure that the shunt on JP10 removed , a 562.5MHz clock @ 12dB is provided to SMA J4, LMK CLKIN , and select the DAC38RF8x_LMF_841 ini file in HSDC Pro .

2,  I run "PLL Auto Tune" and Check whether the DAC PLL is locked . Two things happen, one is PLL0 LED off (PLL1 LED on) ,another is PLL0 LED off (PLL1 LED off) , In both cases, the 150MHz sine is generated, but the loaded data waveform is not generated.

My guess is there is an issue with your test pattern that you are sending to the DAC. Send me your test file and I will try it on our setup. What type of pattern is this? The max frequency should be Fs/2 = 187.5MHz.

sin_data3_02_1A.csvsquare_data3_03_1A.csvThose are 56 data points of sin and square

You test pattern file needs to be a minimum of 4096 samples in increments of 32. With your setup, the file needs to have 4 columns of data. The first column is CHA I data, the second column CHA Q data the third column CHB I data and the fourth column CHB Q data. See attached for an example.

4096_samples_LMF_841_test_file.csv  

For the 821-mode , I used two data files with the same format. Why can one of them be normally displayed through DAC while the other one can't?

Can display.csvCan't display.csv

You keep changing your settings. In the previous post you were using dual DAC. Now you are using single DAC. Which one are you trying to get working?

1,I am trying both dual DAC and single DAC. I want to debug a larger data rate, so that I can load files at the maximum frequency. 

2,For the 821 mod,single DAC,1 IQ pairs,I should need two columns of data, one for DAC A's path I and the other for DAC A's path Q, but the one with only one column of data in one of my files(Can display.csv) can also generate signals normally, while the other one(Can't display.csv) can't. Why?

For #2, are the two columns at least 4096 samples? if larger, is the number of samples an increment of 32 from 4096? 

• Could you help me compile a data file? Requirements: 1. For double DAC, 1 IQ pairs; 2. DAC A is the alternations of a square wave signal with 4 points per period and a square wave signal with 8 points per period. 3. DAC B is the alternations of a square wave signal with 8 points per period and a square wave signal with 16 points per period.
• The example file you gave me has a lot of numbers that are not in 32 increments.
• 

No matter which DAC38RF8x_LMF mode, do I need at least 4096 data points, or 32 increments? 

A minimum of 4096 samples per column. The next large size would be 4096 + 32. The next after that would be 4096 + 64 and so on....