Evaluating common-mode voltage based trade-offs in differential-ended and single-supplied signal conditioning amplifiers

Petkovšek, Marko (author), Zajec, Peter (author)

This paper focuses on a differential voltage measurement in low-voltage automotive devices whose subunits are separated with a low-side safety switch. In contrast to conventional applications with high-side switches, a common-mode voltage (CMV) with negative polarity exists at the input of the signal conditioning circuitry. To overcome the shortage of dedicated integrated circuits capable of withstanding negative CMV, the paper investigates single- and two-stage differential circuits with single-supplied operational amplifiers to find a cost-optimized counterpart. In addition, the proposed procedure tunes the circuit parameters in such a manner to obtain the largest possible full-scale range at the output. Though, such optimization results in very uncommon values for gain and reference voltages. This issue is additionally evaluated for reference voltages that are either cost-effective or more easily accessible to increase the circuit feasibility. Since the impact of resistances on circuits’ behaviour could be diminished to a great extent using high-precision and matched pair resistors, the sensitivity analysis was investigated only for a reference voltage change. Furthermore, a reversed termination of measured voltages results in a simplified reference voltage selection without hindering circuits’ performance, proven by simulation and experimental results.

• Language: English
• Keywords: voltage measurements, common-mode voltage, operational amplifiers, differential-ended signal conditioning, high-power devices, low-side switch
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FE - Faculty of Electrical Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2021
• Number of pages: 18 str.
• Numbering: Vol. 10, iss. 16, art. 1982
• PID: 20.500.12556/RUL-136094
• UDC: 621.31
• ISSN on article: 2079-9292
• DOI: 10.3390/electronics10161982
• COBISS.SI-ID: 74170883
• Publication date in RUL: 12.04.2022

Record is a part of a journal

• Title: Electronics
• Shortened title: Electronics
• Publisher: MDPI
• ISSN: 2079-9292
• COBISS.SI-ID: 523068953

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
• Licensing start date: 17.08.2021

Secondary language

• Language: Slovenian
• Keywords: merjenje napetosti, sofazna napetost, operacijski ojačevalniki, diferenčna prilagoditev signala, močnostni pretvorniki

Projects

• Funder: ARRS - Slovenian Research Agency
• Project number: L2-2619
• Name: Napredni elektronski napajalni modul za avtomobilski katalizator