A 25Gb/s laser diode driver with mutually coupled peaking inductors for optical interconnects

This paper describes a 25Gb/s laser diode (LD) driver based on a standard 65nm CMOS technology for optical interconnects. The LD driver consists of a main driver capable of providing an average current of 30mA and a pre-driver that provides a gain of 20dB. The main driver uses mutually coupled inductors to adjust peaking for various packaging conditions. The pre-driver uses CMOS active feedback to achieve wide bandwidth and high gain, despite compact dimensions and low power consumption. The fabricated circuit achieves 25Gb/s data rates while consuming 142mW (5.2mW/Gb/s) and occupying an area of 0.011mm².