| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an operational panel control device which prevents delay in the falling of a drive power supply voltage. <P>SOLUTION: The control device has a function for controlling an LCD (liquid crystal display) drive power supply voltage control circuit 33 which needs a DC power supply voltage with a relative high voltage to drive an LCD and a DC power supply voltage with a relative low voltage to drive a control circuit of the control device, and supplies and interrupts the drive power supply voltage to the LCD by monitoring a control voltage. The control device creates the DC power supply voltage of the control circuit of the control device by stepping down the drive power supply voltage to the LCD, supplies the drive power supply voltage to the control circuit 33 by a timing signal from a first voltage monitoring means 201b to monitor the stepped down drive power supply voltage of the control circuit, and interrupts the control circuit 33 by a timing signal from a second voltage monitoring means 201c to monitor the drive power supply voltage to the LCD. <P>COPYRIGHT: (C)2004,JPO |
