题目/Title：Design of a 3.24μW, 39nV/√Hz chopper amplifier with 5.5Hz noise corner frequency for invasive neural signal acquisition

作者/Author：
                        Deng Luo,Milin Zhang,Zhihua Wang

会议/Conference：CICC 2018

地点/Location：San Diego, CA, USA

年份/Issue Date：2018.8-11 April

页码/pages：pp. 1 - 4

摘要/Abstract：
This paper proposed the design of a low noise chopper amplifier with low total harmonic distortion (THD) for neural signal acquisition. A Gm-C integrator based DC-servo-loop (DSL) with complementary input and elaborate bias scheme was integrated in the proposed work to improve the linearity and noise performance, which is dominated by DSL of the chopper amplifier in low frequency band. The proposed amplifier was fabricated in TSMC 0.18um CMOS process, occupying an area of 0.2mm2, featuring a power consumption of 3.24渭W/channel under 1.8V supply voltage. The THD for a 5mVpp input is lower than -60dB. An input-referred thermal noise PSD of 39 nV/鈭欻z is measured. The measured input-referred noise is 0.65渭Vrms in the 0.3Hz-200Hz frequency band and 2.14渭Vrms in 200Hz-5kHz, respectively. In addition, the high-pass corner frequency can be precisely configured and linearly adjusted with the external bias current from 0.35Hz to 54.5Hz.