A generic miniature multi-feature programmable wireless powering headstage ASIC for implantable biomedical systems

Area of Science:

• Biomedical Engineering
• Electrical Engineering
• Integrated Circuit Design

Background:

• Wireless powering is crucial for implantable biomedical systems, but requires advanced power management.
• Existing systems face challenges with power supply, current budgets, and functional headstage designs.

Purpose of the Study:

• To propose a single-chip Application-Specific Integrated Circuit (ASIC) for efficient wireless powering of implantable biomedical measurement systems.
• To incorporate digitally programmable features for enhanced power management, including power level detection and power save modes.

Main Methods:

• Design and fabrication of a single-chip ASIC using TSMC 65 nm process.
• Integration of an RF rectifier, bandgap reference, LDO voltage regulator, RF power level detector, and power management block.
• Characterization of RF rectifier efficiency, voltage regulator programmability, and power management duty cycles.

Main Results:

• The ASIC achieved peak RF rectifier efficiencies of 17.9% at 900 MHz and 11.0% at 2.4 GHz.
• The LDO voltage regulator is programmable from 1 V to 1.5 V, driving up to 4 mA load current.
• Power management features offer duty cycles of 6%, 12.5%, or 25%, reducing average power by up to 60%.

Conclusions:

• The developed single-chip ASIC offers a versatile solution for wireless powering of implantable systems.
• Digitally programmable features enable efficient power management, range estimation, and sleep-wake functionality.
• The compact design (1 mm² die area) and low headstage power consumption (~300 μA) make it suitable for various implantable applications.