| 摘要 |
A remote control transmitter is provided to control a constant current flowing through a communication LED(Light Emitting Diode), thereby reducing the power consumption and extending the lifetime of a cell. A communication LED(12) is flickered by using an output voltage of a cell as a power supply, thereby transmitting a remote control signal, which uses light as a transmission medium. A controller(19) consists of an IC, which controls the communication LED to transmit the remote control signal by outputting a control signal for controlling timing of flickering the communication LED. A transistor(Tr1) is serially connected with the communication LED between output ends of the cell. A regulator(21) outputs a constant voltage by using the output voltage of the cell as an input, and supplies electric power to the controller. A driving circuit(20) flickers the communication LED by supplying or cutting a base current flowing through the transistor according to a control signal of the controller. The driving circuit has a switching element turned on or off by the control signal of the controller, and a pair of partial pressure resistors(R2,R3) connected in series with the switching element between output ends of the regulator. A connection node of the pair of partial pressure resistors is connected to base of the transistor so that a constant current is supplied to the communication LED through the base current flowing through the transistor when the switching element is turned on.
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