For the AD5721R what mode should I select if I use VDD=+5.5V and VSS=-5.5V to generate a  +/-4.5V Vout? Shall I use m=8 and c=4 ( +/-10V range) or m=4 and c=2 ( +/-5V range) ?

Question

The transfer function is: 
 
 #AD5721R range setup 
 Vout can not reach +/- 10V if VDD=+5.5V and VSS=-5.5V. Vout can only reach +/-4.5V due to the 1V drop. But how shall I program RA to get +/-4.5V Vout? 
 The documentation states that the register RA is used:

isantos · Accepted Answer

Hi, 
 I suggest using -5V to +5V range if the desired output range is only +/-4.5V to maximize the number of steps being used. Please do note of the supply headroom so that it can properly output the desired voltage. May I know for what application are you going to use this DAC? 
 Cheers, 
 Ivan