公开(公告)号：US10778087B2

公开(公告)日：2020-09-15

申请号：US16345358

申请日：2017-10-16

Applicant: Siemens Aktiengesellschaft

Inventor： Andreas März ,  Mark-Matthias Bakran

IPC: H02M1/38 ,  H02M7/539 ,  H03K17/06

Abstract: A switching half-bridge has two field-effect transistors and a supplementary circuit arranged upstream of a gate terminal of a first field-effect transistor and formed of a first circuit branch having a damping resistor and an inductor connected in series with the damping resistor and a second circuit branch being connected in parallel with the first circuit branch and having a series resistor and an auxiliary switch connected in series with the series resistor. The half-bridge can be switched from a first switching state to a second switching state, wherein while the auxiliary switch is open, a change in the control voltage causes the first circuit branch to temporarily change the gate-source voltage of the first field-effect transistor from the switch-on level to a second switch-off level greater than a first switch-off level, with the gate-source voltage thereafter returning to the first switch-off level.

公开(公告)号：US11290102B2

公开(公告)日：2022-03-29

申请号：US16965870

申请日：2018-12-28

Applicant: Siemens Aktiengesellschaft

Inventor： Andreas März ,  Mark-Matthias Bakran

IPC: H03K17/082 ,  H02M1/08 ,  H03K17/14

Abstract: In a method for protecting a field-effect transistor, which is operated in a switching mode, against an overload current in a switched-on switching state, an electric drain-source voltage between a drain connection and a source connection of the field-effect transistor is detected. The drain-source voltage is compared with a predefined voltage comparison value, and the field-effect transistor is switched into a switched-off switching state in the event that the drain-source voltage is greater than the voltage comparison value. For the purpose of providing a temperature compensation of the protection, the temperature of the field-effect transistor is detected; and the voltage comparison value is adjusted depending on the temperature. The voltage comparison value is, in addition, also dependent on time during the switched-on switching state.