Modulation stabilisation circuit for laser diode output - uses stabilised bias current and superimposed modulation current responsive to laser diode temp.

摘要

The stabilisation circuit has the amplitude of the bias current (Ivor) fed to the laser diode (LD), regulated in dependence on the mean value of the diode optical output, with superimposed modulation of the bias via a modulation current, dependent on a supplied data signal (DATA). The amplitude of the modulation current (Imod) is controlled in dependence on the laser diode temp. Pref. the temp. of the laser diode (LD) is determined via a negative temp. coefficient resistance inserted in a voltage divider circuit. USE - For optical communications with high data rate.