DAC38J82: lane errors not same

Daniel Shi

Prodigy 50 points

Part Number: DAC38J82

Hello,

I have got the register from 0x64 to 0x6C. Below is the value.

Reg 0x64 = 0x0001

Reg 0x65 = 0x0001

Reg 0x66 = 0x0001

Reg 0x67 = 0x0001

Reg 0x68 = 0x7709

Reg 0x69 = 0x0001

Reg 0x6A = 0x0001

Reg 0x6B = 0xBD07

Reg 0x6C = 0xF00F

Seems the lane errors not same, lane 4 and lane 7 have more errors.

Do you have any idea about this problem?

Thanks

Best regards

Daniel

over 1 year ago

0 Geoff Roth over 1 year ago

TI__Expert 5560 points

Hi Daniel,

It sounds like there is a lane length mismatch in the channels you are seeing more errors on. They probably have more loss associated with them.

Regards,

Geoff

0 Daniel Shi over 1 year ago in reply to Geoff Roth

Prodigy 50 points

Hi Geoff,

We have check the layout, the lane length almost equal.

Do you have any other suggestion?

Regards

Daniel

0 Geoff Roth over 1 year ago in reply to Daniel Shi

TI__Expert 5560 points

Hi Daniel,

Something else in the path is causing some issues. Routing too close to VIAs, routing over gnd splits, etc. You should also check your settings on your FPGA to make sure they are appropriate (pre-emphasis and swing) for the input of the DAC.

Regards,

Geoff

Data converters

Data converters forum

DAC38J82: lane errors not same