A low power analog front-end (AFE) circuit dedicated for driving bio-electrochemical sensors and peripheral devices

This work describes a biomedical signal acquisition system using wireless power circuit for bio-electrochemical signal acquisition. The proposed system contains a near-field wireless powering circuit based on 13.56MHz at ISM (industrial, scientific, and medical) band, a low power analog front-end (AFE) circuit dedicated for driving bio-electrochemical sensors, and peripheral devices. The AFE integrated circuit with wireless powering is designed using a 0.18μm 1P6M CMOS process with a core area of 1.383×1.103 mm². The AFE achieves a common-mode rejection ratio of 140dB at 10Hz and power consumption of 11.33μW. The carrier frequency for wireless power transmission is 13.56MHz. The simulation result shows that the wireless power could provide 1mA output current at 1.8V dc output voltage. The peripheral device includes a microcontroller unit (MCU) and a radio frequency (RF) transceiver that could process and transmit the acquired bio -electrochemical signal to computer for data display or storage. The main objective of this proposed system is to make bio-electrochemical signal acquisition quickly and conveniently.