DEVICE FOR CONTROLLING A COLD CATHODE TUBE LAMP

摘要

PURPOSE: A cold cathode tube lamp controlling device is provided to be capable of accessing at a system by making a microcomputer directly interface with a central processing unit of a computer system. CONSTITUTION: The cold cathode tube lamp controlling device comprises a microcomputer(100) which is connected with a central processing unit of a system computer via a smart management bus. The microcomputer(100) judges a power on/off signal and a dimming adjusting signal by the central processing unit, and is supplied with the dimming signal and an on/off signal of the tube from the central processing unit via the smart management bus. The microcomputer(100) compares a feedback current detection signal with a predetermined current value to output a pulse width modulation signal to a converter(120) so as to increase and decrease a driving voltage applied to the lamp from the converter(120).