Why the package temperature is higher than die temperature on Intel® FPGA PAC N3000 card?

When reading temperature by fpgainfo temp command on Intel® FPGA PAC N3000 card, the package temperature may be higher than die temperature.
It's expected behavior.

The package temperature and die temperature are both temperature of the Intel® Arria® 10 FPGA.

The die temperature is the temperature value read by on-board sensor component via the TEMPDIODE pins of Intel® Arria® 10 FPGA.
The accuracy is /-1C.

The package temperature is the temperature value read by internal TSD (Temperature Sensing Diode) of Intel® Arria® 10 FPGA.
The accuracy is /- 5C.