Patent ID: 6771679
Filing Date: 2004-08-03
Classification: H01S

Abstract:
A circuit for controlling a laser diode, comprising:a bias circuit coupled to said laser diode for setting a DC operating point of said laser diode; an amplifier having an output for superimposing an AC signal on said DC operating point, wherein said AC signal modulates an intensity of light emitted by said laser diode, and wherein said amplifier has a control input for controlling a maximum output swing of said amplifier; at least one capacitor connected in functional series between said output of said amplifier and a terminal of said laser diode, whereby said AC signal is capacitively coupled to said laser diode; a control circuit coupled to said control input for setting said maximum output swing; and a programmable memory coupled to said control circuit for storing values for controlling said maximum output swing, whereby an amplitude of said AC signal is controlled, thereby controlling said modulation independently from settings of said DC operating point.