A novel biphasic-current-pulse calibration technique for electrical neural stimulation

Area of Science:

• Biomedical Engineering
• Electrical Engineering
• Neuroscience

Background:

• Neural prosthetic devices require precise electrical stimulation for safe and effective operation.
• Maintaining charge balance during stimulation is a critical challenge in device design to prevent tissue damage.

Purpose of the Study:

• To present a novel calibration technique for neural prosthetic devices.
• To minimize the mismatch between anodic and cathodic current amplitudes in stimulation circuits.

Main Methods:

• The proposed technique integrates digital and analog calibration methods.
• Digital calibration utilizes successive approximation register (SAR) logic and a comparator.
• Analog calibration employs a source follower circuit.

Main Results:

• The calibration technique was simulated using a 0.18 μm high voltage CMOS process.
• The maximum current mismatch achieved was 45 nA, representing less than 0.05% error.
• This demonstrates high precision in charge-balanced stimulation.

Conclusions:

• The developed calibration technique effectively minimizes current amplitude mismatch in neural prosthetic stimulators.
• The achieved precision is vital for enhancing the safety and efficacy of neural prosthetic devices.
• This advancement contributes to the reliable design of next-generation neural prosthetics.