Abstract
A fourth-order ΣΔ modulator (SDM) applied for micro-electro-mechanical systems (MEMS) digital geophones is presented in this paper. At the system stage, the proposed fourth-order SDM adopts a hybrid path technology including a feedforward path and a feedback path. At the design stage, a class AB operational transconductance amplifier with a gain bootstrap structure and chopper technique is employed in the first-stage integrator, which can achieve high DC gain, GBW, (Slew Rate) SR and reduce flicker noise, ensuring high (Signal-to-Noise Ratio) SNR for the proposed SDM. Meanwhile, other key modules are designed to meet basic requirements and achieve low power consumption at the same time. The proposed SDM was implemented in the SMIC 0.18 μm CMOS technology and its final area is 3.09 mm2. When the sampling frequency of 512KHz and signal bandwidth of 2KHz are adopted, the measured results show that the proposed fourth-order SDM can achieve SNR of 101 dB and ENOB of 16.4 bits with less than 5mW power consumption, which meet the requirements of high dynamic range and low power in MEMS digital geophones.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: AEU - International Journal of Electronics and Communications
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
