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DAC in daisy chain mode locks up

Thread Summary

The user encountered an issue with the AD5721RBCPZ-RL7 in a 5 DAC daisy chain configuration where the 2nd DAC's SDO 'locked up', preventing further DACs from being configured. The problem was resolved after the board was reflowed, allowing all DACs to be configured and controlled accurately.
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Category: Hardware
Product Number: AD5721RBCPZ-RL7

Using the AD5721RBCPZ-RL7 in a 5 daisy chain, I'm currently seeing the 2nd DAC SDO 'lock up'. But yet I can configure and control the first 2 DACs out of 5 to do any voltage output I desire accurately. I am currently assuming it is not a PCB fault (I have probed all power lines which seem appropriate) and that I am configuring something incorrectly.

I send in order during separate transactions (tested multiple clk speeds/ clk edge rise times):

"0x0F0000" 5 times during the same transaction.
wait 1 second
"0x040067" 5 times during the same transaction.
wait 1 second
"0x03fff0" 5 times during the same transaction.
The snyc (blue), clk (green) and data (red) going into SDI of the 1st DAC is shown below (all looks appropriate):
SDO of the 1st DAC is shown below (looks appropriate):
SDO of the 2nd DAC is shown below (looks likes its 'locked up'):
As mentioned the voltage output of the first 2 DACs is appropriate/ Max voltage but the following DACs do not change due to the 2nd DACs SDO output.
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