Hi,

I have the following questions.

- 1.

0xFE20 - Voltage loop filter gain

0xFE21 - Voltage loop filter zero

0xFE22 - Fast voltage loop filter gain

0xFE23 - Fast voltage loop filter zero

For the above mentioned register’s, I am able to read back the values from the EVK. We know that these values can be edited through the GUI ”Filter Settings” . But is there any criteria to select this Filter Gain and Filter Zero values?? Or any suggestion for this value selection?

It will be helpful to understand how these values arrived and optimize the values for our requirement.

- 2.

0xFE44 - Smart VOUT low power threshold (P1)

0xFE45 - Smart VOUT high power threshold (P2)

values for the above registers and their equivalent power threshold read from the EVK are

P1 – 73W & Register value – 0x001A (Decimal – 26 )

P2 – 541W & Register value – 0x00C0 (Decimal – 192).

What is the scaling factor(Exponent) used to set the Power threshold into these registers?? For “READ_PIN “(0x97) register the exponent value is -1 (0.5). However I can’t apply this value for the above conversion.

Please kindly help to advise me. Thank you.

For question1, The user can use the GUI to adjust the location of zero and gain in the frequency domain to get desired loop gain bandwidth and phase margin. And the filter gain and zero in the digital domain is calculated by the GUI according on the compensator in the Filter setting window.

For question 2, P1 and P2 are not using linear format as Read_PIN command, they are using their own format. The equation is

P=Register_value*1.6*0.75*(R1+R2)/(2

^{12}*R2*Rsense)Rsense is the current sensing resistor, R1 is the top equivalent resistor of the equivalent voltage divider for VAC and R2 is the bottom equivalent resistor of the equivalent voltage divider for VAC