我使用了机翻来进行翻译，可能存在表述不清的地方，还请谅解
I used machine translation for this text, so there might be places where the wording is unclear. Please bear with me.
以下是我设计的+5.5V降压电路，我想在这个电路的基础上设计-5.5V产生电路
Below is my designed +5.5V buck circuit. I would like to design a -5.5V generation circuit based on this circuit. 
以下是我目前设计的负电压生成电路：
Below is the negative voltage generation circuit I have currently designed.
关于此电路，我有以下几个问题：
I have the following questions regarding this circuit:
1、如果我通过更改参考点的方式来生成负电压的话，输入部分的GND是否也要被设置为-5.5V
If I generate the negative voltage by shifting the reference point, should the GND of the input section also be set to -5.5V?
2、我对于RT\CLK、COMP、FB引脚与其他部分的引脚做了信号地和功率地的单点接地隔离操作，那么SGND和PGND都要设置为-5.5V吗？或者是只有PGND需要更改为-5.5V
I have implemented a single-point grounding isolation between the signal ground and power ground for the RT/CLK, COMP, and FB pins relative to other pins. In this case, should both SGND and PGND be set to -5.5V, or is only PGND required to be changed to -5.5V?
以下为我的PCB设计：
Below is my PCB design.
