A high performance skin impedance measurement circuit for biomedical applications

This paper describes a high-performance impedance measurement circuit for the application of skin impedance measurement in the early detection of skin cancer. A CMRR improvement technique has been adopted for OTAs to reduce the impact of high frequency common mode interference. A modified 3-OTA IA has been proposed to help with the impedance measurement. Such systems offer a quick, non-invasive and painless procedure, thus having considerable advantages over the currently used approach, which is based upon the testing of a biopsy sample. The sensor has been implemented in 65nm CMOS technology and post layout simulations confirms the theoretical claims we made and sensor exhibits sensitivity. Circuit consumes 45uW from 1.5V power supply. The circuit occupies 0.01954mm2 silicon area

Analysis and design of a high precision- high output impedance tissue current driver for medical applications

This paper describes the design and operation of a high output impedance tissue current driver circuit, for use in medical electronics, such as Electrical Impedance Tomography (EIT). This novel architecture was designed for implementation in bipolar technology, to meet the specifications for EIT, namely operating frequency range 10 kHz–1 MHz with a target output resistance of 16 MW. Simulation results are presented, showing that the current source more than met the minimum specification for EIT