| 摘要 |
<p>PROBLEM TO BE SOLVED: To suppres decrease in emitted light quantity from an indicator when the output voltage of a battery in decreased by controlling the driving of a light emitting means according to the output voltage of a battery for driving a light emitting means in the indicator. SOLUTION: The indicator of a coordinate inputting device is provided with a battery 56, a light emitting element 41, a lighting control circuit 51 for driving the light emitting element 41 according to the power to be supplied from the battery 56, and a voltage level detector 52, an NOR circuit 53, and an NPN transistor Q2 and resistors R5 and R6 for controlling the driving of the light emitting element 41 according to the output voltage of the battery 56. When the output voltage of the battery 56 is decreased to a prescribed level or less, the transistor Q2 is turned on according to the output of the lighting control circuit 51 so that a current value running through the light emitting element 41 can be increased in a state in which the resistors R5 and R6 are connected in parallel.</p> |
