Abstract: A circuit that drives a liquid crystal display device, includes an EEPROM having control data that over-drives and provides adaptive brightness intensification, the control data in the EEPROM is protected so as to secure reliability of the EEPROM. The circuit includes a master for over-driving and adaptive brightness intensification, a slave for providing control data to the master, a connector for connecting external writing equipment with terminals on the slave to write the control data into the slave, and an internal power supply of a liquid crystal module that applies an internal supply voltage to the slave. A write control terminal on the slave is grounded in a write mode, and connected to the internal power supply of the liquid crystal module in a liquid crystal module drive mode.