DC decoupled current measurement

US9594097B2 · kind B2 · utility

Assignee

• Infineon Technologies AG · DE

Inventors

• Peter Bogner · Wernberg, AT
• Luca Petruzzi · Eisenlohrsweg, AT

Key dates

• Filing date: Jun 16, 2014
• Grant date: Mar 14, 2017
• Expiry date: Mar 24, 2035

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L2221/00
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A circuit arrangement for measuring a load current provided to a load via a first load terminal of a load transistor is disclosed. In accordance with one example of the invention, the circuit arrangement includes a sense transistor coupled to the load transistor to provide a sense current representing the load current at a first load terminal of the sense transistor. The first load terminals of the load and the sense transistors are at respective floating electric potentials. A floating sense circuit coupled between the load terminals of sense transistor and load transistor, at least in one mode of operation the sense circuit receives the sense current and provides a floating signal representing the sense current. A non-floating measurement circuit is coupled to the sense circuit via a DC decoupling capacitor for transferring the floating signal representing the sense current to the non-floating measurement circuit. The measurement circuit is configured to provide an output signal representing the floating signal and thus the sense current.