An ultrahigh performance laser driver based on novel composite topology enhanced Howland current Source

Area of Science:

• Electrical Engineering
• Optoelectronics
• Instrumentation

Background:

• Laser diodes (LDs) are crucial components in optical wireless communications and LIDAR systems.
• High accuracy and stability of injection current are critical for demanding LD applications.
• Existing LD drivers may lack precision, stability, or adequate protection.

Purpose of the Study:

• To propose a high-precision, high-stability laser diode driver with integrated overvoltage protection.
• To introduce and validate a novel Composite Topology Enhanced Howland Current Source (CTEHCS).
• To address the need for reliable current control in advanced optical systems.

Main Methods:

• Development of a Composite Topology Enhanced Howland Current Source (CTEHCS).
• Integration of a 20-bit DAC and high-precision reference source for stable voltage.
• Implementation of a closed-loop feedback calibration for error reduction.
• Design of a flexible overvoltage protection circuit (4/5/6 V settings).

Main Results:

• The CTEHCS demonstrates high precision, stability, and an extensive regulation range.
• The feedback loop effectively minimizes absolute errors and thermal effects.
• The overvoltage protection circuit successfully safeguards the load.
• Experimental prototype characterization confirmed excellent performance in noise, accuracy, stability, and bandwidth.

Conclusions:

• The proposed LD driver, utilizing CTEHCS and advanced protection, meets stringent requirements for precision and stability.
• This design offers a robust solution for driving laser diodes in critical applications.
• The integrated overvoltage protection enhances device longevity and system reliability.