High-speed CMOS driver for vertical-cavity surface-emitting lasers

摘要

High-speed driver circuits interface with and enhance the performance of vertical-cavity surface-emitting laser (VCSEL) diodes used within fiber optic communication systems, according to embodiments of the invention. A reference diode is formed from a first transistor, and a first current mirror sets a modulation current through the reference diode for driving a light-emitting device. A second current mirror sets a reference biasing current to maintain a constant bias of the reference diode. A first capacitor, charged by a differential amplifier and coupled to the reference diode, supplies complementary charge to the reference diode during differential input voltage transitions. Components of the driver circuit provide asymmetrical operation of the laser, allowing rapid light-emitting-device turn-on and turn-off.