Method and system for electro-absorption modulator drivers in CMOS

A method, comprising:

• in an electro-absorption modulator optically coupled to a laser source and electrically coupled to a modulator driver circuit and a processor, said modulator driver circuit being in a complementary metal oxide semiconductor (CMOS) chip and comprising a summer, a voltage regulator, and level shifting circuitry:
• summing a negative bias voltage and an offset voltage in the CMOS chip utilizing said summer;
• generating a DC termination voltage of lower magnitude than that of said negative bias voltage utilizing said voltage regulator;
• shifting a data signal received from the processor to a negative DC voltage level between said DC termination voltage from said voltage regulator and said negative bias voltage utilizing said level shifting circuitry;
• and
• DC-coupling said level shifted data signal to said modulator utilizing an electrical coupling structure.

A system, comprising:

• an electro-absorption modulator optically coupled to a laser source and electrically coupled to a modulator driver circuit, said modulator driver circuit being in a complementary metal oxide semiconductor (CMOS) chip and comprising:
• a summer for receiving a negative bias voltage and a programmable offset voltage;
• a voltage regulator for receiving an output of the summer and generating a DC termination voltage of lower magnitude than said negative bias voltage;
• level shifting circuitry comprising cascode CMOS transistors and a current mirror for shifting a received data signal to a DC voltage level between said negative DC voltage from said voltage regulator and said negative bias voltage;
• and
• a transmission line for DC-coupling said level shifted data signal to said modulator.