How to load your own ramp pattern data file to TSW3100

Hi Kang,

I found this zip file "TSW3100_Loader_v2p7.zip" on internet.

Could you tell me where to install this "TSW3100_Loader_v2p7.zip". Under TSW3100 folder , there are many sub-folder?

thank you so much,

cheers,thu

Hi Kang,

 I have installed the TSW3100 Loader succesfully. Unfortunately, the guy who supposes to create mat lab file for me is not available.

Could you help me to generate Mat Lab file for a Ramp . Something like :freq.=5Mhz, 0 to 1V Ramp.

I’m using TSW3100 with DAC 5681EVM

Thank you for your help.

Regards,thu

Thu

Use the following MATLAB code and feed the output .mat file to TSW3100 loader.

The data generated is real, fin = 5 MHz, sampled at 1 GSPS.

            fs = 1000e6;
            fin = 5e6;
            N = 32768;
            B = 16;
            t = linspace(0, (N-1)/fs, N);
            w = 2*pi*fin;
            sr = 0.99 * sawtooth(w*t);
            sr = round(sr * 2^(B-1));
            save('ramp.mat','sr');

Hi Hamza,

I used your code but some how I does not come out as expected. Please see attached files.

Does the ramp.mat file suppose to repeat by itself. If it does not ,could you modify it to make it repeat itself?

Secondly, the signal I see under oscilloscope show ~ 1MHz signal not 5MHz

thks,thu

1586.ramp1.doc

Thu,

The TSW3100 will repeat the pattern continuously.

Since you are evaluating the DAC5681 EVM, you will need to select LVDS output from the TSW3100 instead of the 16bQDAC 1file. Also, the transformer output is a high pass filter response. It may filter out the low frequency contents.

If you want the unfiltered ramp response, I would recommend you remove the transformer and use resistor termination instead. Replace R7 and R13 with 25ohms and install R109, R134, R6, R15, and R9. Remove the T1 transformer. The differential output will be at J1 and J2. You can use a differential scope to see the ramp. 

In addition, I would also check the feedback clock from the CDCM7005 to see if it is set up correctly. You can refer to the DAC5681/2/2z EVM user's guide and TSW3100 user's guide for more detail. 

-KH

Hi Kang,

I selected "LVDS" output from the TSW3100, the frequency output doubles from ~ 1.25mhz to 2.5mhz.

1) When I modify R7,R13 to 25ohm, and add R109,134,6,15,9, and remove T1. Should I turn off DACB (sleep)?

2) Could you let me know what to be checked with the CDCM7005?

thks,thu

Hi Kang,

You mentioned that T1 has HPF response. I was using TSW3100 Control to generate 5.1Mhz signal and it shows fairly decent response.

Is T1 really limiting factor?

thks,thu

Thu

Find attached sample configuration files for DAC5681 and CDC7005, for 1 GSPS DAC5681 operation.

DAC5681 is single channel DAC so any settings that are applicable to DAC B (2nd DAC channel on DAC5682z), should be left to their default values.

Regards

Hi Hama,

1) The values which I read from my board are little different from yours. Please advice:

   Hama's file                 Thu's data

   5F                                       5F                           
  00                                       10
  C0                                       80
  73                                      70
  00                                      00
  00                                      00
  0C                                     2C
  FF                                      FF
  00                                      00
  00
  C0
  00
  00
  00
  00
  00

2) Can I replace T2 (ADT4-1T  -  BW :9-600MHZ)  with ADT1-1  (50 ohm  BW: 0.1 to 400mhz).  ADT1-1 has no center tap

     With R22=R26 = 25 ohm?  . With this I can cover lower frequency responses?

thks,thu

Hello Hamza,

I was told that it's possible that transformer T2 (DAC5681) has HPF response and cut off low frequency signals.

I should remove T@ to see low frequency signal.

Could you help to create another ramp file (repeat itself) with Fin=10mhz to make sure that T2 is limiting its BW  before I remove it.

thks,thu

Hi Hamza,

I think that it's generating ramp response. It's,however, the frequency is 2.5mhz instead of 5mhz?

Could you suggest where to look for error?

thanks,thu

Thu

Check the clock going into DAC EVM and the CDC settings and/or use the settings file I sent you.

Regards

hi Hamza,

Did graphs I send to you earlier look OK  (Ramp response) ?

1) 1000 mhz clock going into DAC5681 @ J6 (EXT_VCXO_P)  - green LED is on

2) I load the 2 config files you sent to me yesterday using TSW3100 Config control

3) Using TSW3100 loader (ver 2p7) to9 load your "ramp.mat" file

The output frequency is 2.5mhz?

4) Could you create for me another Ramp file with fin=1mhz, sampling clock=100mhz?

thks,thu

hi Hamza,

Using your " ramp.mat  "  file :

1) Input clock and sampling CLK  =1000mhz  => Ramp output frequency =2.5mhz

2) Input clock and sampling  CLK =100mhz  => Ramp output frequency =0.25mhz

I reduce clock by factor of 10 , the ramp output frequency also reduces by factor of 10 . Does this result implies something?

thu

Hi Hamza,

I think that we have little problem with 2Ghz clock.

 Could you create  another mat lab file with Fin=5mhz, Fsampling =500mhz  , ramp file like the one you created earlier.

thks,thu

Thu

Kindly use the MATLAB code I shared with you earlier to generate any desired frequency of RAMP.

Maximum DAC CLK can be 1 GHz, not 2 GHz.

Regards,

Hamza,

If I understand you correctly based on your mat lab file:

Fin (signal) =5mhz. ;  Clock to DAC =1000mhz ; Sample rate =  ?   (TSW3100 GUI)

thks,thu

Thu

For DAC5681, the DAC CLK and the TSW3100 GUI Sample rate should be the same.

Regards

Hamza,

For the TSW3100 Loader ver2p7 GUI. Are settings for DAC CLK and TSW3100 to be same also?

Second, I have not been able to resolve frequency issue with mat lab file. it shows only 1/2 of what it should be?

thu

Thu

yes, for DAC5681:

DAC CLOCK = Sampling clock = TSW3100 GUI sampling clock

I have double checked my settings by running a DAC5681 here. A snapshot of my DAC GUI is attached and it runs fine.

You should check your clock sources.

Regards,

Hi,

Your DAC5682Z Control GUI is newer than mine. Could you let me know where to download or send me copy?

thks,thu

Software for DAC568x EVM can be downloaded from the following web url

http://www.ti.com/litv/zip/slac497

Software for TSW3100 EVM can be downloaded from

http://www.ti.com/litv/zip/sllc420

Regards,

hello Hamza,

I load your Mat Lab program and using your config files but the output signal is 2.5mhz instead of 5mhz.

Could you help to pin point the issues?

thks,thu

Hardware: TSw3100EVM / DAC5681EVM - input CLOCK=1000mhz

                     Transformer has been removed. Monitor with differential probes

3771.ramp.zip

Thu

I have found a bug in TSW3100 Loader program because of which it works fine for loading complex data (dual channel) into the TSW3100 but not for real data (single channel).

For a work around, please use the following MATLAB code to generate the loading file:

fs = 1000e6;
fin = 5e6;
N = 32768;
B = 16;
t = linspace(0, (N-1)/fs, N);
w = 2*pi*fin;
sr = 0.99 * sawtooth(w*t);
sr = round(sr * 2^(B-1));

sr2(:,1) = sr(1:2:end);
sr2(:,2) = sr(2:2:end);
save('ramp.mat','sr2');

I apologize for inconvenience. We will correct it in our next release.

Regards,