This work proposes a new EEG detection system based on a CMOS lock-in amplifier with programmable gain. The proposed lock-in amplifier consists of five stages: the first and fourth stages are 4-quadrant multipliers with a gain of 8 dB, the second stage is made of two cascaded programmable instrumentation amplifiers (IA), while the third stage is a band-pass filter (BPF) centered at 1 kHz with a gain of 7 dB, and the last stage is a low pass filter (LPF) with a gain of 30 dB and a bandwidth of 150 Hz. A basic building block is the digitally programmable balanced output operational transconductance amplifier (DPOTA), which is used in this work to realize the filters and the IA using 0.25-µm CMOS technology. The proposed lock-in amplifier is characterized by a wide programmable gain ranging from 48dB to 92dB, low power consumption of 71 µW at the maximum gain setting, and low input referred noise of 383nV/ Hz @ 20Hz. PVT and Monte Carlo simulations are also carried out to show the robustness of the proposed lock-in amplifier as a good candidate for EEG detection systems.

Autorentext

Soliman A. Mahmoud a obtenu le diplôme de BSc avec mention en 1994, le diplôme de MSc en 1996 et le diplôme de PhD en 1999, tous au Département d'électronique et de communication de l'Université du Caire, en Égypte. Il est professeur et président du département d'ingénierie électrique et informatique de l'Université de Sharjah, Sharjah, EAU.