A 3.2 Gbps VCSEL driver implemented in 0.18μm CMOS

Abstract

We report on the performance of a 3.2 Gb/s VCSEL driver implemented in foundry n-well 0.18µm CMOS technology. The VCSEL driver utilizes a novel push-pull circuit topology that pushes and pulls modulation current into and out of the VCSEL cavity thus producing symmetric rising and falling edges. Using a commercial VCSEL with a threshold current of 1.2 mA and a slope efficiency of 0.3 mW/mA, the circuit was operated at 1.25, 2.5 and 3.2 Gb/s and produced 2.5 mW of average optical power.