Abstract
This paper presents a SC 50 Hz notch filter for an analog to digital acquisition channel in an IoT water management sensor node. The notch filter is used to attenuate the unwanted 50 Hz interference, allowing to reduce the required effective resolution of the ADC, which is a ΣΔ modulator with a sampling frequency of 2 MHz. Due to the large ratio between the sampling frequency and the pole frequency, which increases the capacitor values dispersion, charge division branches are used to allow the delivery of a small charge using a larger capacitor, reducing the capacitor spread. The factor by which the value of the capacitors can be increased is controlled by the number of set/reset cycles that are used in the charge division branches. The maximum number of cycles is dependent on the time constants of each node and the gain value of the amplifiers. The notch filter has a total power dissipation below 300 μW and electrical simulations show an attenuation of approximately 30 dB in the unwanted 50 Hz signal.
| Original language | English |
|---|---|
| Title of host publication | 2017 IEEE International Symposium on Circuits and Systems (ISCAS) |
| Subtitle of host publication | From Dreams to Innovation |
| Publisher | IEEE |
| ISBN (Electronic) | 978-1-4673-6853-7 |
| ISBN (Print) | 978-1-5090-1427-9 |
| DOIs | |
| Publication status | Published - 25 Sep 2017 |
| Event | 50th IEEE International Symposium on Circuits and Systems, ISCAS 2017 - Baltimore, United States Duration: 28 May 2017 → 31 May 2017 |
Publication series
| Name | IEEE International Symposium on Circuits and Systems |
|---|---|
| Publisher | IEEE |
| Volume | September-2017 |
| ISSN (Electronic) | 0271-4310 |
Conference
| Conference | 50th IEEE International Symposium on Circuits and Systems, ISCAS 2017 |
|---|---|
| Country | United States |
| City | Baltimore |
| Period | 28/05/17 → 31/05/17 |
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Keywords
- Bandpass filters
- Internet of things
- Sensor nodes
- Water management
Cite this
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A 50 Hz SC notch filter for IoT applications. / Serra, Hugo; Oliveira, Joao Pedro; Paulino, Nuno.
2017 IEEE International Symposium on Circuits and Systems (ISCAS): From Dreams to Innovation. IEEE, 2017. 8050904 (IEEE International Symposium on Circuits and Systems; Vol. September-2017).Research output: Chapter in Book/Report/Conference proceeding › Conference contribution
TY - GEN
T1 - A 50 Hz SC notch filter for IoT applications
AU - Serra, Hugo
AU - Oliveira, Joao Pedro
AU - Paulino, Nuno
N1 - This work was supported by the Portuguese Foundation for Science and Technology under project PEst-OE/EEI/UI0066/2013 and Ph.D. Grant SFRH/BD/87476/2012, and PROTEUS in the scope of the European Unions H2020 Programme for research, technological development and demonstration under grant agreement No. 644852.
PY - 2017/9/25
Y1 - 2017/9/25
N2 - This paper presents a SC 50 Hz notch filter for an analog to digital acquisition channel in an IoT water management sensor node. The notch filter is used to attenuate the unwanted 50 Hz interference, allowing to reduce the required effective resolution of the ADC, which is a ΣΔ modulator with a sampling frequency of 2 MHz. Due to the large ratio between the sampling frequency and the pole frequency, which increases the capacitor values dispersion, charge division branches are used to allow the delivery of a small charge using a larger capacitor, reducing the capacitor spread. The factor by which the value of the capacitors can be increased is controlled by the number of set/reset cycles that are used in the charge division branches. The maximum number of cycles is dependent on the time constants of each node and the gain value of the amplifiers. The notch filter has a total power dissipation below 300 μW and electrical simulations show an attenuation of approximately 30 dB in the unwanted 50 Hz signal.
AB - This paper presents a SC 50 Hz notch filter for an analog to digital acquisition channel in an IoT water management sensor node. The notch filter is used to attenuate the unwanted 50 Hz interference, allowing to reduce the required effective resolution of the ADC, which is a ΣΔ modulator with a sampling frequency of 2 MHz. Due to the large ratio between the sampling frequency and the pole frequency, which increases the capacitor values dispersion, charge division branches are used to allow the delivery of a small charge using a larger capacitor, reducing the capacitor spread. The factor by which the value of the capacitors can be increased is controlled by the number of set/reset cycles that are used in the charge division branches. The maximum number of cycles is dependent on the time constants of each node and the gain value of the amplifiers. The notch filter has a total power dissipation below 300 μW and electrical simulations show an attenuation of approximately 30 dB in the unwanted 50 Hz signal.
KW - Bandpass filters
KW - Internet of things
KW - Sensor nodes
KW - Water management
UR - http://www.scopus.com/inward/record.url?scp=85032680371&partnerID=8YFLogxK
U2 - 10.1109/ISCAS.2017.8050904
DO - 10.1109/ISCAS.2017.8050904
M3 - Conference contribution
SN - 978-1-5090-1427-9
T3 - IEEE International Symposium on Circuits and Systems
BT - 2017 IEEE International Symposium on Circuits and Systems (ISCAS)
PB - IEEE
ER -