Circuit arrangement for driving a semiconductor laser

• Main Authors: MUEHLNIKEL,GERD, WERNZ,HORST, WIESMANN,THEO
• Format: Patent
• Language: English; German
• Published: 11.09.1986
• Edition: 4
• Subjects: BASIC ELECTRIC ELEMENTS; DEVICES USING STIMULATED EMISSION; ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; TRANSMISSION

The invention relates to a driver stage for driving a semiconductor laser diode whose output signal can be regulated by means of a pilot tone which is superimposed on the preliminary current and/or on the modulation current, containing a differential amplifier and current-impressing circuits, and is characterised in that a first differential amplifier and a first current-mirror circuit, which supplies its emitter, are provided for producing and regulating the laser modulation current, in that a second current-mirror circuit is provided for producing and regulating the laser preliminary current, in that a second differential amplifier, which is controlled by a pilot generator and a pilot regulator and whose one collector is connected to the emitter of the first differential amplifier is provided, and a third current-mirror circuit which supplies the emitter of this second differential amplifier is provided in order to superimpose alternately on the preliminary current and on the modulation current a pilot component having a first auxiliary current, in that a third differential amplifier, which is likewise driven by the pilot generator and the pilot regulator and whose one collector is likewise connected to the emitter of the first differential amplifier is provided, and a fourth inlet flow, which supplies the emitter of this third differential amplifier with a second auxiliary current, is provided, in such a manner that the collectors of the second and third differential amplifiers, which are connected to the emitters of the first differential amplifier, supply their auxiliary currents in synchronism, for superimposition on the modulation current (Fig. 1).