Sub-threshold standard cell library design for ultra-low power biomedical applications

Area of Science:

• Low-power integrated circuit design
• Biomedical electronics
• CMOS technology

Background:

• Portable and implantable biomedical devices require minimal power consumption to maximize battery life.
• Small bio-signal bandwidths (kHz range) allow for relaxed operating frequency requirements.
• Sub-threshold digital circuits offer an optimal power/speed tradeoff for these applications.

Purpose of the Study:

• To design and characterize a sub-threshold standard cell library for energy-efficient biomedical applications.
• To evaluate the power and performance benefits of sub-threshold design compared to conventional approaches.

Main Methods:

• Design of a 56-cell sub-threshold standard cell library using 0.18-µm CMOS technology.
• Methodology validation through schematic design, transistor width scaling, layout, and characterization.
• Comparative performance analysis using a 5-stage ring oscillator and an ECG FIR filter against a commercial standard cell library.

Main Results:

• The designed sub-threshold library achieved a total power saving of 95.62%.
• Leakage power was reduced by 97.54% compared to the commercial standard cell library implementation.
• The sub-threshold approach demonstrated significant power efficiency for biomedical signal processing.

Conclusions:

• Sub-threshold standard cell libraries are highly effective for developing ultra-low-power biomedical devices.
• This design methodology significantly reduces both dynamic and leakage power consumption.
• The developed library provides a viable solution for extending battery life in power-constrained biomedical applications.