MSP430F5500: About the monitoring voltage of the VBUS terminal

Thank you for your prompt response.

It is assumed that an interrupt will occur when the VBUS voltage drops below the VLAUNCH voltage = 3.75V that I also told you, and that an interrupt will occur when the VBUS voltage returns to a voltage higher than the 3.75V voltage. It was, but it wasn't.
As a phenomenon confirmed here, an interrupt occurs when VBUS drops to about 4.1V with no fluctuation in 3.3V supplied to [MSP430F5500].
I have confirmed that an interrupt occurs when the voltage is higher than VLAUNCH voltage = 3.75V, so I am wondering and asking a question.

Hello,

The description you provided for VBUS monitoring interrupts is correct. If enabled, you would get an interrupt as the voltage rises above VLAUNCH threshold, and as is dips below VLAUNCH. Keep in mind the USB LDOs will shutoff automatically if VBUS voltage dips below VLAUNCH level. 

There should not be any correlation between MSP430 DVCC and VBUS voltage as they are different supply rails. The exception of course being if the output of the USB 3.3V LDO, VUSB, is connected externally to DVCC, and thus the whole MSP430 is being powered via the USB connection. I that case the LDO output should be stable at 3.3V until it gets shutoff when VBUS voltage drops below VLAUNCH leel.

Hopefully this helps. 

Thank you for teaching me.
Please tell me a little more.

I am using "MSP430F5500", but the voltage of the VBUS terminal drops to about 4.1V, and an interrupt occurs.
I checked it with "MSP430F5500" mounted on multiple boards, but all interrupts are occurring in the same way.
The voltage of the VBUS terminal has dropped only to about 4.1V.
An interrupt is occurring at a voltage higher than the VLAUNCH voltage of 3.75V.

Therefore, I think that the threshold value at which the VBUS pin interrupt occurs is MAX 3.75V.
Does the VLAUNCH threshold have a range?
For example, if there is a variation of about 3.75V ± 10%, I am convinced.
If there is variation, please tell me the range of variation.
Thank you.

excuse me.
I couldn't use English well, so I understood that it wasn't communicated well.

The threshold value of VLAUNCH is MAX 3.75V, which is stated in the data sheet, but I think there is a variation with respect to 3.75V.

Do you agree with that idea?

If 3.75V varies, I would like to know the range of the variation.

For example, if the variation is 10%, it will be 4.125V at + 10%, so I am trying to understand that an interrupt will occur even if the voltage of the VBUS terminal drops to 4.1V.