OPT3101: Enabling illumination crosstalk calibration using external temp sensor

So I summarized the mechanism as follows:

If I don't set the registers in 7.4.2.1, the external temp sensor won't work, and the external temp phase calib won't work too.

If I set the registers in 7.4.2.1, the external temp sensor will work, and the external temp phase calib will work too.

But how about the internal temp phase calib? 

According to real operation, the internal temp phase calib is not disabled even when I set the registers in 7.4.2.1 and let the external temp sensor work.

I can read the temp from external sensor, and the internal temp phase calib is working at same time. How to prevent from both working? I don't see any options in register for choosing which one to work. Or should I clear all the values of coefficients of one to disable? What should I do?

Yeah, I set EN_TILLUM_READ to 1, and set the rest as described in 7.4.2.1.

But how to disable internal temp calib for xtalk/phase offset when I enabled external temp calib and use it to calibrate xtalk/phase offset?

I have tried this, but this cannot be found in datasheet, so I can't say this is the correct way to do and explain this to my supervisor. But after you say it, I'm relieved now. And it will be helpful if this fact is decribed in a document.

Thanks!

Thanks!

By the way, what kind of circumstance do I need to use external temprature sensor? Mainly because of the higher resolution?