| 摘要 |
PURPOSE: To attain low power consumption and stable data communication by providing a transmitting unit with a voltage booster circuit and transmitting data by a voltage higher than the power supply voltage. CONSTITUTION: When a transmission instruction is outputted from a user, a CPU 9 supplies a control signal S to a switch circuit 7 and simultaneously controls carrier generating circuits 1, 2 to generate a carrier S1 and a high frequency carrier S2 . Then a synthesized carrier S3 generated by a carrier synthesizing circuit 3 is inputted to a transmitting signal generating circuit 4 and a booster circuit 8 and voltage Vd which is twice power supply voltage Vcc is generated from the circuit 8 and supplied to a light emitting unit 5 and a light emitting unit drive circuit 6 through the circuit 7. On the other hand, the circuit 4 synthesizes a data signal S4 and the synthesized carrier S3 to form a transmitting signal S5 and transmits the signal S to the circuit 6 to switch a transistor TR1 and voltage is applied to the element 5 to generate an optical signal. Thereby even when a portable low voltage power supply is used for a power supply, a signal can be stably transmitted at a prescribed voltage level. |
