10 Gb/s 4-PAM Ring Modulator Driver

High speed and low power transmission on optical interconnections can be achieved using ring-based optical modulators. 3D-integration of the ring modulator on top of the driver chip allows compact and cheap transmitters. 4-PAM modulation is considered for the first time for a high data rate.This paper presents a 10 Gb/s ring modulator driver with high and  adjustable  swing.  The  circuit  is  designed  in austria microsystems 0.35 µm SiGe BiCMOS technology with a power consumption of 5.87 pJ/bit for 3 V output swing.