Over 70-GHz 4.9-V ppdiff InP linear driver for next generation coherent optical communications

This paper presents a 86.8-GHz bandwidth 4.9-V ppdiff (peak-to-peak differential) linear electro-optical (E/O) modulator driver fabricated in III-V Lab’s 0.7-µm InP DHBT technology. On-wafer measurements exhibit a differential gain of 15.1 dB at 0.2 GHz and a 4.1-dB peaking gain at 51 GHz. Record bandwidth and maximum peaking-frequency, for a lumped linear driver, are obtained. Very high quality 100-Gb/s NRZ and 50GBd PAM-4 output eye diagrams have been measured. A good measurement and EM-simulation agreement is shown. The InP linear driver power consumption is respectively 0.94 and 1.2 W at 4.1 and 4.9-V ppdiff output swings.