I'want to use the "Voltage and Current output Ranges on the same Terminal" Function as depicted in Figure 77 at the AD5422 Manual together with the Boost Transistor. I'am using schematics as attached. I use the current output setting of 0...20 mA and a Load Current of 270E. AVss is set to -5VDC. When I set a higher binary value of about 50000 digits, the schematics draws a current of about 100mA and the AD5422 gets hot. If I use a Supply Voltage AVdd of more than 20V, the DAC enters Overtemperature State.
Is there something wrong with the schematics?