The EVAL-AD7280AEDZ has cell balance turned on even with register 0x14 set to 0x00 and all the CB registers set to 0. This is on a test bench with resistors simulating a 12 cell battery that start with a very uniform voltage drop across each resistor. the EVAL drives more than a 0.5 volt from the slave to the master AD7280 so the voltage drop across the slave resistors is 0.5V less than the master resistors. I have tried writing all of the registers and still cannot turn this off. I cannot connect this EVAL to an actual set of battery cells without being able to control the cell balance.
Apologies for the delay. I was trying to reach out the product owner as I am not familiar with the design of the board and I'll let him response to this once I reached him.
However, when CBx is set to 0 then the output should also be set to 0V. So I cannot understand as well why it didn't turned off and upon power up by default the cell balance register are set to 0. Have you probe all of the CBx pins? Can you also share to us your circuit connections for us to understand it better?