A 35 nV/√Hz Analog Front-End Circuit with Adjustable Bandwidth and Gain in UMC 40 nm CMOS for Biopotential Signal Acquisition
Abstract
1. Introduction
2. Overall Architecture Design
3. Analysis and Design of the Proposed CCIA
3.1. Design of the Main Op-Amp
3.2. Design of DC Servo Loop (DSL)
3.3. Design of Ripple Rejection Loop (RRL)
4. Analysis and Design of the Proposed PGA-LPF
5. Results and Discussion
6. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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PVT | TT, 1.2 V 27 °C | SS, 1 V 0 °C | FF, 1.4 V 80 °C | FS, 1.2 V 27 °C | SF, 1.2 V 27 °C |
---|---|---|---|---|---|
Integral noise (μVrms) | 1.03 | 0.71 | 2.26 | 0.83 | 1.41 |
Reference | [21] | [17] | [22] | [23] | [24] | [25] | This work |
Process (nm) | 180 | 65 | 40 | 180 | 180 | 180 | 40 |
Supply (V) | 1 | 1 | 1.2 | 1.2 | 1.2 | 1.8 | 1.2 |
Area (mm2) | 0.19 | 0.1 | 0.069 | 0.062 | N/A | 0.072 | 0.18 |
Power (μW) | 2.14 a | 1.8 a | 2.8 a | 0.507 a | 0.8 a | 3.66 a | 8.94 b |
IRN (μVrms) | 2.1 (1–200 Hz) | 6.7 (0.5–100 Hz) | 7.1 (1–5 kHz) | 0.67 (0.5–150 Hz) | 1.7 (0.5–150 Hz) | 2.86 (1–5 kHz) | 1.0360 (0.5–1 kHz) |
Noise density (nV/√Hz) | 133 | 60 | 80 | 85 | N/A | N/A | 35 |
Zin (Ω) | 4.46 G @0.01 Hz | 30 M @10 Hz | 1.6 G | 150 M @1 Hz | N/A | 1.8 G @10 Hz | 368 M @50 Hz |
Bandwidth (Hz) | 0.5–750 | 0.5–100 | 0.5–5 k | 0.1–1.2 k | 1–900 | 0.1–5.1 k | 0.5–1 k |
Gain (dB) | 40 | 40 | 25.7 | 30–45 | 43–57 | 26.04 | 40–52 |
CMRR (dB) | N/A | >134 | >78 | >65 | 85 | N/A | >111 |
Results | Measure | Measure | Measure | Simulation | Simulation | Simulation | Simulation |
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Liu, L.; Wang, B.; Xu, Y.; Lin, X.; Yang, W.; Ding, Y. A 35 nV/√Hz Analog Front-End Circuit with Adjustable Bandwidth and Gain in UMC 40 nm CMOS for Biopotential Signal Acquisition. Sensors 2024, 24, 7994. https://doi.org/10.3390/s24247994
Liu L, Wang B, Xu Y, Lin X, Yang W, Ding Y. A 35 nV/√Hz Analog Front-End Circuit with Adjustable Bandwidth and Gain in UMC 40 nm CMOS for Biopotential Signal Acquisition. Sensors. 2024; 24(24):7994. https://doi.org/10.3390/s24247994
Chicago/Turabian StyleLiu, Lu, Bin Wang, Yiren Xu, Xiaokun Lin, Weitao Yang, and Yinglong Ding. 2024. "A 35 nV/√Hz Analog Front-End Circuit with Adjustable Bandwidth and Gain in UMC 40 nm CMOS for Biopotential Signal Acquisition" Sensors 24, no. 24: 7994. https://doi.org/10.3390/s24247994
APA StyleLiu, L., Wang, B., Xu, Y., Lin, X., Yang, W., & Ding, Y. (2024). A 35 nV/√Hz Analog Front-End Circuit with Adjustable Bandwidth and Gain in UMC 40 nm CMOS for Biopotential Signal Acquisition. Sensors, 24(24), 7994. https://doi.org/10.3390/s24247994