| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an LED display device that makes fading-in and fading-out actions. <P>SOLUTION: A PWM control IC 12 drives an LEDR 13, LEDG 14, and LEDB 15 by using a pulse having a fixed cycle period. A CPU 11 controls the control IC 12 to maintain the maximum duty ratio of the pulse for a fixed period of time after increasing the duty ratio of the pulse step by step, or to maintain the minimum duty ratio of the pulse for a fixed period of time after reducing the duty ratio of the pulse step by step. Consequently, the LEDR 13, LEDG 14, and LEDB 15 gradually become brighter or darker. In addition, these LEDs 13, 14, and 15 can be controlled independently. <P>COPYRIGHT: (C)2004,JPO&NCIPI</p> |
