An ultra low-power precision sample-and-hold circuit for biomedical application
In this project, the student was able to realize a low-power precision sample-and-hold (S/H) circuit for biomedical application based on switched-capacitor circuit. The performance of the circuit in this work is comparable with some previously published works on precision S/H circuits. The S/H ci...
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| Other Authors: | |
| Format: | Final Year Project (FYP) |
| Language: | English |
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2010
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| Online Access: | http://hdl.handle.net/10356/40448 |
| _version_ | 1824455534108999680 |
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| author | Mah, Sai Lei |
| author2 | Chan Pak Kwong |
| author_facet | Chan Pak Kwong Mah, Sai Lei |
| author_sort | Mah, Sai Lei |
| collection | NTU |
| description | In this project, the student was able to realize a low-power precision sample-and-hold (S/H) circuit for biomedical application based on switched-capacitor circuit. The performance of the circuit in this work is comparable with some previously published works on precision S/H circuits.
The S/H circuit was designed to work with a supply voltage of 1.8V and was realized in 0.18 μm CMOS technology. The S/H circuit was developed from a capacitive-reset gain switched-capacitor circuit that has benefits of insensitive to op-amp input offset, finite open-loop gain of op-amp, low power and rail-to-rail characteristic. Capacitor-mismatch compensation was then incorporated into it to make the circuit insensitive to capacitor mismatch. In response to intentionally introduced 2% of capacitor mismatch, output of the new circuit only changes by a few micro-percent with respect to that of circuit without any intentionally introduced capacitor mismatch. The parameters that were used to check the precision of the S/H circuit are hold pedestal and total harmonic distortion. In the end, the student managed to achieve hold-pedestal less than 0.081 mV and -76 dB of total harmonic distortion that corresponds to 12.62 bits of ENOB in response to 1-Vpp and 1-kHz sinusoidal input at 128 kHz of sampling frequency.
Operational amplifier (op-amp) used in the circuit plays a major part in contributing to the power consumption of the circuit. Thus, student has focused on reducing power consumption of the op-amp. With a target of achieving less than 13 μW of power consumption, some transistors in the op-amp may works in moderate or weak inversion. At last, the student managed to design an op-amp that consumes 12.04 μW that gives 0.395 μW/pF of power efficiency. The Figure of Merits achieved is 8.30×10-3 μA/MHz. |
| first_indexed | 2025-02-19T03:39:44Z |
| format | Final Year Project (FYP) |
| id | ntu-10356/40448 |
| institution | Nanyang Technological University |
| language | English |
| last_indexed | 2025-02-19T03:39:44Z |
| publishDate | 2010 |
| record_format | dspace |
| spelling | ntu-10356/404482023-07-07T16:23:42Z An ultra low-power precision sample-and-hold circuit for biomedical application Mah, Sai Lei Chan Pak Kwong School of Electrical and Electronic Engineering DRNTU::Engineering::Electrical and electronic engineering::Electronic circuits In this project, the student was able to realize a low-power precision sample-and-hold (S/H) circuit for biomedical application based on switched-capacitor circuit. The performance of the circuit in this work is comparable with some previously published works on precision S/H circuits. The S/H circuit was designed to work with a supply voltage of 1.8V and was realized in 0.18 μm CMOS technology. The S/H circuit was developed from a capacitive-reset gain switched-capacitor circuit that has benefits of insensitive to op-amp input offset, finite open-loop gain of op-amp, low power and rail-to-rail characteristic. Capacitor-mismatch compensation was then incorporated into it to make the circuit insensitive to capacitor mismatch. In response to intentionally introduced 2% of capacitor mismatch, output of the new circuit only changes by a few micro-percent with respect to that of circuit without any intentionally introduced capacitor mismatch. The parameters that were used to check the precision of the S/H circuit are hold pedestal and total harmonic distortion. In the end, the student managed to achieve hold-pedestal less than 0.081 mV and -76 dB of total harmonic distortion that corresponds to 12.62 bits of ENOB in response to 1-Vpp and 1-kHz sinusoidal input at 128 kHz of sampling frequency. Operational amplifier (op-amp) used in the circuit plays a major part in contributing to the power consumption of the circuit. Thus, student has focused on reducing power consumption of the op-amp. With a target of achieving less than 13 μW of power consumption, some transistors in the op-amp may works in moderate or weak inversion. At last, the student managed to design an op-amp that consumes 12.04 μW that gives 0.395 μW/pF of power efficiency. The Figure of Merits achieved is 8.30×10-3 μA/MHz. Bachelor of Engineering 2010-06-15T09:18:19Z 2010-06-15T09:18:19Z 2010 2010 Final Year Project (FYP) http://hdl.handle.net/10356/40448 en Nanyang Technological University 89 p. application/pdf |
| spellingShingle | DRNTU::Engineering::Electrical and electronic engineering::Electronic circuits Mah, Sai Lei An ultra low-power precision sample-and-hold circuit for biomedical application |
| title | An ultra low-power precision sample-and-hold circuit for biomedical application |
| title_full | An ultra low-power precision sample-and-hold circuit for biomedical application |
| title_fullStr | An ultra low-power precision sample-and-hold circuit for biomedical application |
| title_full_unstemmed | An ultra low-power precision sample-and-hold circuit for biomedical application |
| title_short | An ultra low-power precision sample-and-hold circuit for biomedical application |
| title_sort | ultra low power precision sample and hold circuit for biomedical application |
| topic | DRNTU::Engineering::Electrical and electronic engineering::Electronic circuits |
| url | http://hdl.handle.net/10356/40448 |
| work_keys_str_mv | AT mahsailei anultralowpowerprecisionsampleandholdcircuitforbiomedicalapplication AT mahsailei ultralowpowerprecisionsampleandholdcircuitforbiomedicalapplication |