| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a light emitting diode driving device which performs both feedback control over drive voltages to be applied to LEDs and PWM control over drive currents. <P>SOLUTION: The light emitting diode (LED) driving device 10 comprises a drive voltage generator 11 which generates a drive voltage Vout for the LEDs, a drive current control unit 12 which performs PWM control over drive currents iW1 to iW3 flowing to the LEDs, and a monitor voltage generator 13 which monitors the drive voltage Vout and generates a monitor voltage Vm having a superposed variation component of the drive voltage Vout based upon a predetermined reference voltage Vref during an off period of the drive currents. The drive voltage generator 11 performs feedback control over the drive voltage Vout so that feedback voltages VW1 to VW3 match the reference voltage Vref during an on peroid of the drive current and performs feedback control over the drive voltage Vout so that the monitor voltage Vm match the reference voltage Vref during the off period of the drive currents. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
