| 摘要 |
<p>An optical transmitter having an automatic output controlling function converts monitor current of a laser into a voltage and detects an average value of the voltage. The average value is compared with a mark-space ratio outputted from a mark-space ratio detection circuit by a bias control circuit, by which a bias circuit is controlled. Meanwhile, the average value described above is divided by the mark-space ratio from the mark-space ratio detection circuit by an operation circuit, and a resulting value is compared with a reference voltage (Vref) and amplified by a pulse current controller. The pulse current driver is controlled with the amplified output of the pulse current controller. Finally, outputs of the pulse current driver and the bias circuit are added to drive the laser. <IMAGE></p> |
