Hi
the datasheet of UCD9222 said the output of eADC feeds the Nonlinear Gain block.what is the function of Nonlinear Gain block?why the output of eADC should be enlarged by Nonlinear Gain block?and which one to choose Gain0,Gain1..or Gain5?
For the compensating filter transfer function,How to decide the value of K F and Q of H(s)?thanks
The non-Linear Gain Block provides a faster response to a disturbance on the output of the rail while allowing the rail to have good DC regulation under steady state operation. The gain is added after the eADC to make the response of the compensator larger to the disturbance.
The gain values relate to the range of eADC output error values, see Fusion Digital Power Designer GUI screen shot, for this example when the error is within +3 and -4 LSBs (eADC Thershold) the Non-Linear Gain is 1.0 (this is the GAIN2 value). When the eADC error is within +4 and -5 the gain is 1.75 (Gain1 and Gain3 values) and for larger errors it will be 2.00 (Gain0 and Gain4 values).
This provides a quicker resonse to the a disturbance that exceeds the defined thresolds.