DAC38J82EVM: no data on DAC output

deepak kumar32

Intellectual 350 points

Part Number: DAC38J82EVM

This is in my reference to my previous post;

e2e.ti.com/.../2368063

I have the Xilinx JESD working now with EVM with LMF =821 configuration.

I do not see any JESD alarms in DAC3X82 GUI.

If I use SYSREF pulses then SYREF and SYNC goes low after 8 pulses. JESD_TREADY also go low. I am not sure what I am missing in this conguration.

So, I am using continuous SYSREF in LM4828 tab as it keeps all above needed signals high. I also do not get FIFO errors in GUI and I am passing data.

However, there is no output from DAC (checked at J2 and J8 on EVM).

I appreciate your help in advance.

Thanks,

over 7 years ago

0 jim s over 7 years ago

TI__Guru* 91947 points

Deepak,

We are looking into this.

Regards,

Jim

0 jim s over 7 years ago in reply to jim s

TI__Guru* 91947 points

Deepak,

How can you have the link working with LMF = 821 if the KC705 only has 4 lanes routed? The highest value you can ever use for L is 4.

Regards,

Jim

0 deepak kumar32 over 7 years ago in reply to jim s

Intellectual 350 points

Jim,

I have a similar board that can support 8 lanes. Also, instead of I & Q, I am sending only I data on JESD lane.

Thanks,
D

0 jim s over 7 years ago in reply to deepak kumar32

TI__Guru* 91947 points

DAC38J84 100MHz NCO Test.pptxDeepak,

Setup the DAC to only use the internal NCO and see if you can get an output. Follow the example attached. This will verify the DAC is getting a valid clock, the power is OK and the SPI is working.

Regards,

Jim

0 deepak kumar32 over 7 years ago in reply to jim s

Intellectual 350 points

Hello Jim,

Sorry for late response. I am able to get the NCO working correctly. What should I test next to verify that JESD data is received and output correctly?

Thanks,

0 jim s over 7 years ago in reply to deepak kumar32

TI__Guru* 91947 points

D,

Send data from the FPGA, verify that the SYNC goes low from the DAC, then high after ILA sequence has completed. If you get pass this stage, clear the DAC error registers then read them back to check for any errors. Basically, follow the steps in section 8.3 of the data sheet.

Regards,

Jim

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DAC38J82EVM: no data on DAC output