| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To reduce power consumption of an LED drive by lowering the output voltage thereof. <P>SOLUTION: The LED drive comprises a first transistor 15 connected between input and output terminals, a reference potential generation circuit connected between the output terminal and a reference potential, a load circuit having an LED connected between the output terminal and the reference potential, a detection circuit for detecting a current flowing through the LED in the load circuit, a voltage conversion circuit 30 for converting an output signal from the detection circuit, a comparator for comparing the output voltage from the reference potential generating circuit with a signal output from the conversion circuit to output a control signal, and a second transistor 16 for controlling the amount of current by varying the input voltage of the first transistor depending on a control signal from the comparator wherein power consumption is reduced by lowering the voltage of the detection circuit using the conversion circuit thereby lowering the output voltage from the LED drive. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
