error with AD5669R



I use a AD5669-1 in my design, and I meet some strangeous errors that confused me.


I configure the input register as follow.

1, start

2, configure Internal reference;

3, configure DAC channel A;

4, configure DAC channel C;

5, configure DAC channel E;

6, configure DAC channel G;

7, stop;


I configure the device AD5669R-1 according the I2C standard and the protocal defined in the datasheet. I peek the signal SDA and SCL with oscilloscope, and the signal is right on the wire. But after configuration, the VREFIN/VREFOUT pin output a voltage of 1.82V, while the correct output should be 1.25V. Besides, all the configured channels output a voltage of 2.08V, while the unused channel output a voltage of 0.58V.

What's the possible reason for this error?


Besides, after power-on and before configuration, the  VREFIN/VREFOUT pin and all channel output the same voltage of 0.58V