Being modulated light method and the LED modulated light method of radiating the modulated light circuit and

摘要

PPROBLEM TO BE SOLVED: To provide a dimming method and circuit capable of illuminating with light intensities in two or more steps, such as raising the intensity of only a specific LED or blinking it, when dimming by simple control using a versatile IC or with a single kind of PWM signal, and to provide a distress warning arrangement using the same. PSOLUTION: Using a positive phase PWM signal of an arbitrary duty ratio and a negative-phase PWM signal provided by inverting the positive-phase PWM signal, a plurality of LEDs are controlled for illumination with a first light intensity based on the positive-phase PWM signal and a second light intensity based on at least the negative-phase PWM signal. PCOPYRIGHT: (C)2010,JPO&INPIT