LED-aandrijfinrichting voor overspanningsbeveiliging en inschakelduurbesturing.

摘要

An LED driving device comprises a PWM IC including an RT/CT terminal operated by a power voltage and generating and outputting a sawtooth wave voltage of a predetermined frequency, a COMP terminal to which a comparison voltage compared with the sawtooth wave voltage is inputted, and an output terminal generating and outputting a pulse signal turned off in a section in which a level of the sawtooth wave voltage is higher than a level of the comparison voltage and turned on in a section in which the level of the sawtooth voltage is lower than the level of the comparison voltage. The LED driving device sets up the comparison voltage inputted to the COMP terminal of the PWM IC to be 0 when an error voltage corresponding to a difference between a both end voltage of an LED array and a predetermined reference voltage is less than a predetermined level.