| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a load control device that implements improved duty ratio accuracy by preventing an inaccurate duty ratio in a high duty range. <P>SOLUTION: A triangular wave generation circuit 5 generates a triangular wave VC1 from a supply voltage VI supplied to a load 2. A pulse drive circuit 6 supplies to the load 2 a driving pulse having a duty ratio depending on a comparison of the triangular wave VC1 generated by the triangular wave generation circuit 5 with a reference voltage Vk. A reference voltage generation circuit 7 increases or decreases the reference voltage Vk as the supply voltage VI increases, to reduce the duty ratio of the driving pulse. When the supply voltage VI is equal to or lower than a predetermined voltage, a frequency adjustment circuit 8 reduces the frequency of the triangular wave VC1 generated by the triangular wave generation circuit 5 to reduce the frequency of the driving pulse. <P>COPYRIGHT: (C)2013,JPO&INPIT |
