The following picture is my SCH and my question is on the state of pin “sw”。 下面的图片是我的原理图，我的问题是关于sw管脚（pin1，2，3，4，5）的工作状态。
The following picture is the Screenshot of oscilloscope . The probe is on the PIN "SW".We can see from the picture that when time is Toff the voltage of PIN “SW” is over the “0V”。 下图是示波器的截图。这里观察的是PIN “SW”的电压。当dc-dc进入 Toff时间后，Pin“SW”的电压高于0V。
The last picture is from the datasheet of LM76003 .We can see from the picture that when time is Toff the voltage of PIN “SW” is under the “0V”。最后一幅图是来自LM76003的datasheet。我们可以看出，当器件键入Toff时间后，“SW”上的电压是低于0V的。
Why in our design the state of the voltage on PIN “sw” is different from the datasheet？为什么我们设计的电路中 pin “sw”上的电压状态和datasheet不一样？
