A Power Efficient Low Noise Preamplifier for Biomedical Applications

摘要

In biomedical recording system, the preamplifier determines the overall performance of the system in terms of power dissipation and noise efficiency. In the literature, the preamplifier using Folded Cascode Current Splitting (FCCS) Operational Transconductance Amplifier (OTA) is reported. In this paper, a preamplifier which adopts the current stealing technique to the FCCS OTA is proposed. The proposed preamplifier is designed in UMC 180 nm CMOS process with a power consumption of 1.5 μW and studied through simulation. From the simulation results, it is found that the preamplifier has a mid-band gain of 40.17 dB, pass band of 0.008 Hz to 1.7 kHz and total input-referred noise voltage of 2.99 μV_(rms) over a bandwidth of 0.1 Hz-13.6 kHz. The noise efficiency factor (NEF) of the proposed preamplifier is 2.60. The input-referred noise and NEF of the proposed preamplifier is almost same as that of FCCS OTA, but it has a lower power consumption by a factor of 1.6.