| 摘要 |
PROBLEM TO BE SOLVED: To obtain a laser drive pulse current where vibrations generated on a pulse current is restrained with inductive components of IC pins. SOLUTION: A semiconductor laser drive circuit, which generates a current to be supplied to a semiconductor laser in accordance with a laser modulation signal, is provided with laser drive current generating circuits 101-110 for generating a 1/10 the current of a laser drive current value. The laser drive current generating circuits 101-110 contain delaying means for delaying the laser modulation signal. Differential amplifying circuits, which consists of pairs of transistors whose emitters, are connected with each other, pairs of resistors whose one ends are connected with the respective collectors of pairs of the transistors and other ends of which are connected with a voltage source, and current sources connected with the emitters of the pairs of the transistors are contained. Current weighting is performed on the rising edge and falling edge of the laser drive current, when a pulse current is generated by arbitrarily combining the delaying means or the differential amplifying circuits of the ten laser drive current generating circuits 101-110, and a pulse current is obtained. Thereby the vibrations of output current is restrained.
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