题目/Title:Design of A Low Noise Neural Recording Amplifier for Closed-loop Neuromodulation Applications
作者/Author:
Deng Luo,Milin Zhang,Zhihua Wang
会议/Conference:ISCAS 2018
地点/Location:Florence, Italy
年份/Issue Date:2018.27-30 May
页码/pages:pp. 1 - 4
摘要/Abstract:
This paper presents the design of a low-noise chopper amplifier for neural signal acquisition in the presence of the in-band stimulation artifacts that exist in the closed-loop neuromodulation system. In order to avoid saturation due to the artifacts, the gain of the amplifier is designed to be 26dB. A modified positive feedback loop is introduced to boost both inband and DC input impedance. The Gm-C integrator without external capacitors is used in the DC-Servo-Loop (DSL) to filter out the electrode offset. To further enhance the linearity, the voltage divider technique is employed at the input of the Gm-C integrator. The proposed work was fabricated using a 0.18um CMOS process. The amplifier consumes 3.42渭W under 1.8V supply voltage, while occupying an area of 0.219mm2. The measured input-referred noise is 1.12渭Vrms (1 Hz-200 Hz) and 4.65渭Vrms (200 Hz-5 kHz). A DC input impedance of 90M惟, a CMRR of 103dB, and a PSRR of 78dB are achieved as well.