SN65HVD1781: Could you tell me about part number of SN65HVD1781?

Hello Sekiguchi-san,

There is no difference between these two part numbers. The "G4" suffix was originally intended to distinguish devices using a "green" mold compound, meaning that it is RoHS compliant and Sb/Br free. That distinction is no longer needed, though, since all of the devices in this family meet TI's green packaging guidelines.

You can read more about green packaging at TI here:

www.ti.com/.../Environmentally_Friendly_Solutions.pdf

Regards,
Max