AD5422 not working

Hi,

I'm trying to get an AD5422 working. I can't get an output signal or register data from a readback.

 Here it the schematics I use:

 

DVcc = 3.36V, AVdd = 11,93V, AVss = 0V, Clear = 0V;

Vout stays always about 16mV.

 

  1. I removed IC13, R57 and T11 an connected Vout with +Vsense. Same problem.
  2. I changed the AD5422. No change.

 

Here the plots from the SPI-bus.

Yellow = Latch, Blue = CLK, Purple = SDI, Green = SDO

 Reset:

 

 

Set config (Rext = on, 0-5 Range, Enable output):

 

 Set data value:

 

Readback config-reg:

 

 

 I can't figure out, what is wrong.

Can someone pleas assist me?   

 

Regards

 Sephan