Direct downloads for specific TV panel firmware files like are generally not available on official manufacturer websites. These files are typically used for "flashing" or repairing a TV mainboard to match a specific LCD panel and are often found on specialized technician forums or file-sharing sites. Official Methods to Update Firmware
Visit the official Dynabook (Toshiba Support) Portal and enter your specific model number (65U7750) to see if a downloadable USB update is available. Download TOSHIBA 65U7750 Panel K650WD7 LF330 part3 rar
Select or Update Now to download and install the latest version directly over Wi-Fi. Via USB (Official Support): Direct downloads for specific TV panel firmware files