LED CONTROL DEVICE USING CONSTANT VOLTAGE, CONSTANT CURRENT, PWM CONTROL

摘要

The present invention relates to a LED control device adopting a constant voltage, a constant current, and a PWM control method at the same time. For the device, a constant current circuit is composed of a differential amplifier in which an output signal is proportional to a difference between two input signals and a comparator which compares the input signals and outputs the comparison resu a constant voltage circuit is comprised of a differential amplifier in which an output signal is proportional to a difference between two input signals and a comparator which compares the input signals and outputs the comparison resu a positive voltage +V and a negative voltage -V on both ends of a resistor are connected to be inputted to the constant current circuit and the constant voltage circuit; and a MCU is connected in order to input a setting voltage stored in advance to the constant current circuit and the constant voltage circuit. [Reference numerals] (11) Constant voltage circuit; (13) Constant current circuit; (15) Resistance; (AA,BB,DD,EE) Setting voltage; (CC) Applied voltage