AbstractA low power CMOS instrumentation amplifier used for biomedical applications is presented in this paper. It consists of a low power operational amplifier with CMFC structure. By analysis and optimization of the parasitic effects and parameters, instrumentation amplifier has better performance in every aspect. This simulation result shows that, in the case of guaranteed bandwidth, the amplifier can suppress flicker noise interference effectively. The instrumentation amplifier designed in 0.5μm CMOS technology with 3.3V power supply shows a dynamic range of 70.1dB and 23.48ns settling time within 0.05% accuracy. The main amplifier dissipates 10.5mW power. It also includes a bias circuit that dissipates 2.2mW power.