DAC39RF10: Signal output error with standalone

JH,

You didn't tell us what the issue they are seeing is so we can't comment on a possible root cause.

Regards,

Geoff

Hello Geoff,

Thank you for your reply.

The title of the above post is the issue. My customer tried to output a signal from the device alone with the above settings, but failed. Please answer the questions above.

Regards,

JH

Hi Geoff,

For additional information, the DAC39RF10 chipset's Device CLK 3.932GHz and SYSREF CLK 1.92MHz are being input normally, 
but the dac output is still not output. Please check.

Thanks.
KB

Hi KB,

This has been assigned to the engineer in charge of this part.  He will be in touch in a few days.

Regards,

Geoff

Hey KB, 

SYSREF is only required for certain use cases (SUBCLASS 1 operation as well as NCO synchronization if register NCO_SYNC_SRC is 1 or 2). 

Its difficult to know what could be going wrong just from a register dump. Could you provide what clock frequency they are providing the DAC (Fdac)? In addition I think its easiest to first try to get an output in DDS mode as this doesn't require the JESD interface. 

Below is a sequence I used to get a 2.2GHz tone with a 10GHz clock in DDS mode. This doesn't require any input from the FPGA as the device uses the internal NCO's as a tone source. Could you have them try this? The output should be a single tone at 2.2GHz*(Fdac/10E9Hz)This way we can confirm their output stage is working. 

DAC39RF10.write[0x2e0, 0x0] # Ensure datapath is low
DAC39RF10.write[0x100, 0x0] # JESD_EN = 0
DAC39RF10.write[0x102, 0x2] # Set JESD_M to 2 (implying single DUC enabled)
DAC39RF10.write[0x300, 0x2] # Set DDS_EN (NCO_EN still 0)
DAC39RF10.write[0x321, 0x52] # Program FREQ word of DUC0 NCO
DAC39RF10.write[0x322, 0xb8] # Program FREQ word of DUC0 NCO
DAC39RF10.write[0x323, 0x1e] # Program FREQ word of DUC0 NCO
DAC39RF10.write[0x324, 0x85] # Program FREQ word of DUC0 NCO
DAC39RF10.write[0x325, 0xeb] # Program FREQ word of DUC0 NCO
DAC39RF10.write[0x326, 0x51] # Program FREQ word of DUC0 NCO
DAC39RF10.write[0x327, 0x38] # Program FREQ word of DUC0 NCO
DAC39RF10.write[0x318, 0xff] # Program AMP level of DUC0 NCO (max value 0dB)
DAC39RF10.write[0x319, 0x7f] # Program AMP level of DUC0 NCO (max value 0dB)
DAC39RF10.write[0x304, 0x0] # ensure SPI SYNC is low
DAC39RF10.write[0x304, 0x1] # ensure SPI SYNC is high (high edge used for sync)
DAC39RF10.write[0x304, 0x0] # ensure SPI SYNC is low
DAC39RF10.write[0x2e4, 0x11] # Map DUC0 to both DACA and DACB. Can also set to 0x01 to only use DACA and 0x10 to only use DACB
DAC39RF10.write[0x2e2, 0x0] # Set DUC_GAIN to 0dB on all DUCS as only single DUC being used
DAC39RF10.write[0x2e0, 0x1] # Enable Datapath to get output
Note this is for NRZ output mode (default mode).

Regards, 

Matt

Hi Matt

Thank you for your reply.
The Fdac frequency is 3.932.16GHz.

Regarding DDS Mode, we will inform you of the results after testing on the EVM board and Target board.

Regards,
KB

Hi Matt

Attached are the results measured in DDS Mode with the EVM board, showing that it operates correctly.

However, our own board still does not produce any output.

The attached register values are those written to the target board, and they are values that work correctly on the EVM board.

Please check if there is any issue with the input sequence or if other setting values might be incorrect.

Regards,

KB

DAC39RF10.write(0x0000,0x80)
time.sleep(0.1)
DAC39RF10.write(0x0101,0x04)
DAC39RF10.write(0x0102,0x04)
DAC39RF10.write(0x0103,0x13)
DAC39RF10.write(0x0108,0x10)
DAC39RF10.write(0x0109,0x21)
DAC39RF10.write(0x010A,0x01)
DAC39RF10.write(0x010B,0x01)
DAC39RF10.write(0x0103,0x13)
DAC39RF10.write(0x0103,0x11)
DAC39RF10.write(0x01C2,0x01)
DAC39RF10.write(0x02E1,0x07)
DAC39RF10.write(0x02E3,0x01)
DAC39RF10.write(0x02E4,0x11)
DAC39RF10.write(0x02E8,0x00)
DAC39RF10.write(0x0723,0x1F)
DAC39RF10.write(0x0724,0x0F)
DAC39RF10.write(0x0725,0x1F)
DAC39RF10.write(0x0726,0x0F)
DAC39RF10.write(0x072E,0x14)
DAC39RF10.write(0x072F,0x14)
DAC39RF10.write(0x0739,0x14)
DAC39RF10.write(0x0100,0x01)
DAC39RF10.write(0x02E0,0x01)
DAC39RF10.write(0x0107,0xFF)
DAC39RF10.read(0x02E8) # = 0x00
DAC39RF10.read(0x0107) # = 0x24
DAC39RF10.read(0x02E8) # = 0x00
DAC39RF10.write(0x02E0,0x00)
DAC39RF10.write(0x0100,0x00)
DAC39RF10.write(0x0300,0x02)
DAC39RF10.read(0x02E0) # = 0x00
DAC39RF10.write(0x02E0,0x00)
DAC39RF10.write(0x02E4,0x10)
DAC39RF10.read(0x02E0) # = 0x00
DAC39RF10.write(0x02E0,0x00)
DAC39RF10.write(0x02E4,0x00)
DAC39RF10.read(0x02E0) # = 0x00
DAC39RF10.write(0x02E0,0x00)
DAC39RF10.write(0x02E4,0x01)
DAC39RF10.read(0x02E0) # = 0x00
DAC39RF10.write(0x02E0,0x00)
DAC39RF10.write(0x02E4,0x11)
DAC39RF10.read(0x02E0) # = 0x00
DAC39RF10.write(0x0327,0x10)
DAC39RF10.write(0x0326,0x46)
DAC39RF10.write(0x0325,0xAA)
DAC39RF10.write(0x0324,0xAA)
DAC39RF10.write(0x0323,0xAA)
DAC39RF10.write(0x0322,0xAA)
DAC39RF10.write(0x0321,0xAA)
DAC39RF10.write(0x0320,0xAA)
DAC39RF10.write(0x0304,0x00)
DAC39RF10.write(0x0304,0x01)
DAC39RF10.read(0x02E0) # = 0x00
DAC39RF10.write(0x0319,0x40)
DAC39RF10.write(0x0318,0x00)
DAC39RF10.write(0x02E0,0x01)

Geoff Roth said:

u tried saving the config of the EVM off to a file, restarting

Hi all

I have resolved the issue mentioned above.

The cause of the problem was a cold solder joint found in the BALUN component.

If I have any further questions during additional development,

I will be sure to ask.

Thank you for your assistance.

Regards,

KB