A low-power integrated bioamplifier with active low-frequency suppression.

Area of Science:

• Electrical Engineering
• Biomedical Engineering
• Microelectronics

Background:

• Dense multichannel recording devices require miniaturized, low-power bioamplifiers.
• Traditional bioamplifiers often face limitations in size and power consumption due to component requirements for frequency filtering.

Purpose of the Study:

• To develop a low-power bioamplifier optimized for massive integration in dense multichannel neural recording systems.
• To achieve reduced size and maintain high input impedance without compromising performance.

Main Methods:

• Implemented a low-noise amplifier with an active integrator in the feedback path for active low-frequency suppression.
• Utilized a long integrating time constant with a small integrated capacitor and MOS-bipolar equivalent resistor.
• Employed a transconductance-efficiency design methodology for micropower operation in a 0.18-μm CMOS process.

Main Results:

• Achieved a midband gain of 50 dB and an input-referred noise of 5.6 μVrms.
• The bioamplifier occupies less than 0.050 mm² of chip area.
• Dissipates only 8.6 μW of power, demonstrating micropower operation.

Conclusions:

• The developed bioamplifier is suitable for massive integration in dense multichannel neural recording devices.
• The active low-frequency suppression technique effectively reduces size without sacrificing performance.
• The design enables efficient, high-performance neural signal acquisition for in vivo recordings.