| 摘要 |
PURPOSE:To obtain a diode which performs an ultrahigh-speed optical modulation at a low power consumption by constructing the driver circuit for a light emitting diode used for optical communication with a series circuit of a level shift diode, and first and second Schottky gate FETs, and controlling the diode by means of the first FET. CONSTITUTION:The circuit for driving a light emitting diode 13 is constructed with a series circuit of a level shift diode 14, a first Schottky gate FET 11 and a second Schottky gate FET 12, and the anode terminal 17 of the diode 14 is set to the ground potential and the source of the FET 12 is set to the potential of a power supply 16. When the diode 13 is made to emit a light with this constitution, the voltage to be applied to a gate input terminal 15 of the FET 11 is lowered below the threshold voltage to make the FET inoperable, and the diode 13 is made to emit a light by the FET 12. When the light is extinguished, the voltage to be applied to an input terminal 18 of the FET 12 is controlled to make the FET 12 inoperable, making the light extinguishing ratio of the diode 13 high. |
