An Analog Interface Circuit for Capacitive Angle Encoder Based on a Capacitance Elimination Array and Synchronous Switch Demodulation Method
This paper presents an analog interface application-specific integrated circuit (ASIC) for a capacitive angle encoder, which is widely used in control machine systems. The encoder consists of two parts: a sensitive structure and analog readout circuit. To realize miniaturization, low power consumpti...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2019-07-01
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| Series: | Sensors |
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| Online Access: | https://www.mdpi.com/1424-8220/19/14/3116 |
| _version_ | 1798025427491487744 |
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| author | Bo Hou Bin Zhou Xiang Li Zhenyi Gao Qi Wei Rong Zhang |
| author_facet | Bo Hou Bin Zhou Xiang Li Zhenyi Gao Qi Wei Rong Zhang |
| author_sort | Bo Hou |
| collection | DOAJ |
| description | This paper presents an analog interface application-specific integrated circuit (ASIC) for a capacitive angle encoder, which is widely used in control machine systems. The encoder consists of two parts: a sensitive structure and analog readout circuit. To realize miniaturization, low power consumption, and easy integration, an analog interface circuit including a DC capacitance elimination array and switch synchronous demodulation module was designed. The DC capacitance elimination array allows the measurement circuit to achieve a very high capacitance to voltage conversion ratio at a low supply voltage. Further, the switch synchronous demodulation module effectively removes the carrier signal and greatly reduces the sampling rate requirement of the analog-to-digital converter (ADC). The ASIC was designed and fabricated with standard 0.18 µm CMOS processing technology and integrated with the sensitive structure. An experiment was conducted to test and characterize the performance of the proposed analog interface circuit. The encoder measurement results showed a resolution of 0.01°, power consumption of 20 mW, and accuracy over the full absolute range of 0.1°, which indicates the great potential of the encoder for application in control machine systems. |
| first_indexed | 2024-04-11T18:18:53Z |
| format | Article |
| id | doaj.art-6e9c4c333e3a44cda47eb1bcc02bebb2 |
| institution | Directory Open Access Journal |
| issn | 1424-8220 |
| language | English |
| last_indexed | 2024-04-11T18:18:53Z |
| publishDate | 2019-07-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Sensors |
| spelling | doaj.art-6e9c4c333e3a44cda47eb1bcc02bebb22022-12-22T04:09:49ZengMDPI AGSensors1424-82202019-07-011914311610.3390/s19143116s19143116An Analog Interface Circuit for Capacitive Angle Encoder Based on a Capacitance Elimination Array and Synchronous Switch Demodulation MethodBo Hou0Bin Zhou1Xiang Li2Zhenyi Gao3Qi Wei4Rong Zhang5Engineering Research Center for Navigation Technology, Department of Precision Instrument, Tsinghua University, Beijing 100084, ChinaEngineering Research Center for Navigation Technology, Department of Precision Instrument, Tsinghua University, Beijing 100084, ChinaEngineering Research Center for Navigation Technology, Department of Precision Instrument, Tsinghua University, Beijing 100084, ChinaEngineering Research Center for Navigation Technology, Department of Precision Instrument, Tsinghua University, Beijing 100084, ChinaEngineering Research Center for Navigation Technology, Department of Precision Instrument, Tsinghua University, Beijing 100084, ChinaEngineering Research Center for Navigation Technology, Department of Precision Instrument, Tsinghua University, Beijing 100084, ChinaThis paper presents an analog interface application-specific integrated circuit (ASIC) for a capacitive angle encoder, which is widely used in control machine systems. The encoder consists of two parts: a sensitive structure and analog readout circuit. To realize miniaturization, low power consumption, and easy integration, an analog interface circuit including a DC capacitance elimination array and switch synchronous demodulation module was designed. The DC capacitance elimination array allows the measurement circuit to achieve a very high capacitance to voltage conversion ratio at a low supply voltage. Further, the switch synchronous demodulation module effectively removes the carrier signal and greatly reduces the sampling rate requirement of the analog-to-digital converter (ADC). The ASIC was designed and fabricated with standard 0.18 µm CMOS processing technology and integrated with the sensitive structure. An experiment was conducted to test and characterize the performance of the proposed analog interface circuit. The encoder measurement results showed a resolution of 0.01°, power consumption of 20 mW, and accuracy over the full absolute range of 0.1°, which indicates the great potential of the encoder for application in control machine systems.https://www.mdpi.com/1424-8220/19/14/3116angle encodercapacitance elimination arrayswitch synchronous demodulation methodapplication-specific integrated circuit |
| spellingShingle | Bo Hou Bin Zhou Xiang Li Zhenyi Gao Qi Wei Rong Zhang An Analog Interface Circuit for Capacitive Angle Encoder Based on a Capacitance Elimination Array and Synchronous Switch Demodulation Method Sensors angle encoder capacitance elimination array switch synchronous demodulation method application-specific integrated circuit |
| title | An Analog Interface Circuit for Capacitive Angle Encoder Based on a Capacitance Elimination Array and Synchronous Switch Demodulation Method |
| title_full | An Analog Interface Circuit for Capacitive Angle Encoder Based on a Capacitance Elimination Array and Synchronous Switch Demodulation Method |
| title_fullStr | An Analog Interface Circuit for Capacitive Angle Encoder Based on a Capacitance Elimination Array and Synchronous Switch Demodulation Method |
| title_full_unstemmed | An Analog Interface Circuit for Capacitive Angle Encoder Based on a Capacitance Elimination Array and Synchronous Switch Demodulation Method |
| title_short | An Analog Interface Circuit for Capacitive Angle Encoder Based on a Capacitance Elimination Array and Synchronous Switch Demodulation Method |
| title_sort | analog interface circuit for capacitive angle encoder based on a capacitance elimination array and synchronous switch demodulation method |
| topic | angle encoder capacitance elimination array switch synchronous demodulation method application-specific integrated circuit |
| url | https://www.mdpi.com/1424-8220/19/14/3116 |
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