| 摘要 |
PURPOSE:To operate sufficient performance in a Ga/s band even if a DC bias circuit is mounted out of a photodetector driver by connecting a microstrip line having predetermined characteristic impedance to the output terminal of the driver, and connecting a terminating resistor and a DC bias unit to the other end of the line. CONSTITUTION:A light emitting element driving circuit drives a light emitting element 1 connected to an output terminal, and has a light emitting element driver 11, a transistor 13, a microstrip line 14, a terminating resistor 15, and a resistor 16. In such a driving circuit, the output terminal is connected to the cathode of the element 1 grounded at its anode, and one end of the line 14 having predetermined characteristic impedance is connected to the connecting point of the output terminal to the element 1. The other end of the line 14 is grounded to a reference potential via the resistor 15, and a DC bias circuit having an inductance 13 and a transistor 12 is connected to the connecting point of the line 14 to the resistor 15. |
