A large current and high speed laser diode driver using switch position modification

This paper describes how to realize the high speed laser diode driver (LDD) circuit with high performance signal and large output current to drive the laser diode device. Based on the introduced idea of "Switch Position Modification (SPM)", two types of LDD circuit architectures, including "Combination Switch Mode (CSM)" and "Source Follower Mode (SFM)", have been proposed to satisfy the output signal requirements. Under the corresponding design specification, the CSM architecture was selected to realize the effective LDD circuit design. Moreover, the signal integrity problems, such as overshoot, undershoot and slew-rate, have also been improved in the new CSM architecture. In addition, appropriate transistor size selection and circuit combination can further amend the signal waveform. The LDD circuit was realized in a 0.6-μm CMOS technology. And the output current can reach several hundred milliampere with good signal integrity in the experimental simulation results. Thus the introduced "Switch Position Modification" idea and the proposed "Combination Switch Mode" architecture assure the high performance LDD circuit realization and signal output.