Since this is an OEM board, there is no single "official" global website. You must source the firmware from reputable technical forums or specialized electronics portals like Kazmi Elecom Critical Precautions: Check Resolution:
Turn off the main power switch of the TV and unplug it from the wall outlet.
Ensure your TV remains plugged into a reliable power source during the upgrade. Interruptions will corrupt the mainboard. Step-by-Step Installation Guide
If the installation process does not go as planned, use these quick fixes to resolve the issue.
Reconnect power. Some boards begin the update automatically, indicated by a flashing standby light; others may require holding the power button while plugging it in.