Digital compensator design tool for DSC

[LZhang1]

I am new to NXP DSC digital power products;
I would like to ask if NXP provides tools for digital compensator design (loop compensation)?
Thank you very much!

MC56F80xxx 

[xiangjun_rong]

Hi,

Frankly speaking, I am not very clear about your question.

do you want to design a buck DC/Dc converter and using the peaking current mode to control?

Pls refer to the an4716 and check if it is what you expected.

https://www.nxp.com.cn/docs/en/application-note/AN4716.pdf

Hope it can help you

BR

Xiangjun Rong

[LZhang1]

Dear @xiangjun_rong 

Tks for your reply.

refer below picture, Equation 19, how to get B2、B1、B0、A2、A1、A0；

Do you need to consider decimal floating-point to fixed-point conversion? MC56F807xx series with FPU function, can be used directly?
Does MC56F807xx need to consider the interrupt delay in digital calculation, or the delay caused by other functional modules, and finally combine it into a phase delay? How do I feed back to Ax\Bx?

and What are the interactions in the adjustment process?

Is there an intuitive display tool? For example, you can plot a Bode plot;

Or can we only invert the s domain every time we change the values of Ax and Bx, and then draw the graph?

I am a little confused about this, and I would like to ask you to help me sort out and answer questions.

[xiangjun_rong]

Hi,

Q1)Do you need to consider decimal floating-point to fixed-point conversion? MC56F807xx series with FPU function, can be used directly?

>>>>>I suppose that you use fslesl library for the IIR filter:

https://www.nxp.com/design/design-center/software/embedded-software/real-time-control-embedded-softw...

For the DSP56800E and DSP56800EX core, the frac16 (fixed point) format is used. For the DSP56800EF core, it appears that the library only supports frac16/frac32 (fixed point) format rather than float format.

Q2)Does MC56F807xx need to consider the interrupt delay in digital calculation, or the delay caused by other functional modules, and finally combine it into a phase delay? How do I feed back to Ax\Bx?

and What are the interactions in the adjustment process?

>>>>>From DSC perspective, the DSC only computes an IIR for each new coming x(n) data, the delay is NOT considered.

Q3)Is there an intuitive display tool? For example, you can plot a Bode plot;

There is a QE design lite tools, but there is not a website to download. After you install the CodeWarrior for DSP56800E ver8.3, the tools will be installed automatically.

Q4)Or can we only invert the s domain every time we change the values of Ax and Bx, and then draw the graph?

The Ax/Bx is only dependent on the transfer function in S domain and the sampling rate, after the transfer function is determined, sampling rate is determined, Ax/Bx are determined.

Hope it can help you

BR

Xiangjun Rong