| 摘要 |
PURPOSE:To improve the reliability of a light emitting element by decreasing as less as possible the duty ratio in signal transmission. CONSTITUTION:A pulse code corresponding to an input key 3 is outputted continuously from a pulse code generating circuit 2. While a transistor (TR)2 is turned on for a required time through the detection of the leading of the 1st pulse code, the pulse code switches the TR1. Thus, a light emitting element is driven corresponding to the pulse code. The light emitting element 1 is not driven because the pulse code is inputted to the TR1 after the prescribed time. Thus, the duty ratio in driving the light element 1 is decreased by setting properly the on/off time of a TR2 by means of a switching control means comprising a leading detection circuit 5 and timer circuits 6 and 7 or the like. |
