A 0.18 μm biosensor front-end based on 1/f noise, distortion cancelation and chopper stabilization techniques

Area of Science:

• Electrical Engineering
• Biomedical Engineering
• Sensor Technology

Background:

• Electrochemical biosensors require low-noise, low-distortion front-end circuits.
• 1/f noise and distortion are significant challenges in sensor signal processing.
• Current-mode biosensing applications demand efficient transimpedance amplifiers (TIAs).

Purpose of the Study:

• To present a novel fully differential transimpedance amplifier (TIA) front-end circuit.
• To address 1/f noise and distortion using canceling techniques.
• To achieve low noise, low distortion, and low power consumption for electrochemical biosensing.

Main Methods:

• A canceling-based architecture for a fully differential TIA was designed.
• Optimization methods were employed to minimize noise and distortion at low current.
• The front-end was fabricated using a 0.18 μm CMOS process.
• Characterization and testing within a wireless sensing system were performed.

Main Results:

• The fabricated front-end demonstrated effective noise and distortion cancellation.
• Cyclic voltammetry (CV) test results from electrochemical sensors were successfully obtained.
• The circuit achieved a low current consumption of 50 μA at a 1.8 V supply.

Conclusions:

• The proposed canceling-based TIA front-end effectively mitigates 1/f noise and distortion.
• The design is suitable for low-power, current-mode electrochemical biosensing applications.
• Integration into a wireless sensing system validates its practical utility.