Electronic field device with transceiver protecting circuit

US11233392B2 · kind B2 · utility

Assignee

• Endress+Hauser SE+Co. KG · DE

Inventors

• Armin Wernet · Rheinfelden (Baden), DE
• Michael Dötsch · Lindenberg im Allgäu, DE

Key dates

• Filing date: Sep 17, 2018
• Grant date: Jan 25, 2022
• Expiry date: Sep 17, 2038

Classification

• Technology area (CPC H): Electricity
• CPC primary: H02H11/002
• WIPO field: Electrical machinery, apparatus, energy
• WIPO sector: Electrical engineering

Abstract

The present disclosure relates to an apparatus for determining and/or monitoring at least one process variable of a medium in a containment, comprising a sensor unit and an electronics unit, wherein the electronics unit includes a transceiver unit and a transceiver protecting unit for limiting an input voltage of the transceiver unit to a first transceiver voltage value. According to the present disclosure, the transceiver protecting unit includes a first limiting unit and a transistor unit, the transistor unit connected in series with the transceiver unit, wherein the first limiting unit is connected in parallel with transceiver unit and to a control terminal of the transistor and is configured to control an input voltage for the control terminal of the transistor to a predeterminable control value such that the input voltage of the transceiver unit is limited to the first transceiver voltage value.