Reverse Polarity Protection for MOSFETS
AssigneeInfineon Technologies AG
InventorsBenno Koeppl, Karl-Dieter Hein, Frank Auer
Life of this patent
Estimating the term…
Abstract
The invention relates to a control circuit and a corresponding method for controlling MOSFETs coupled to the control circuit. The MOSFETs are coupled to a load to couple the load to a power supply, or the MOSFETs are coupled to a generator. In case of inverted polarity, the control circuit switches the MOSFETs to their conducting state to prevent damaging the MOSFETs.
Claims24
A method for operating a control circuit and at least one MOSFET, the control circuit controlling the MOSFET to couple a load to an energy source, the control circuit designed to be supplied with a non-inverted supply polarity from an energy storage device, the method comprising causing the MOSFET to switch to a conducting state upon detection that an inverted supply polarity from the energy storage device is being applied to the control circuit.
A method for operating a control circuit controlling a rectifier that comprises MOSFETs, the method comprising causing the MOSFETs to switch to their conducting state when the rectifier is coupled to an inverted polarity, wherein the control circuit is supplied by an energy storage device designed for operation with a non-inverted polarity.
A controller circuit for controlling a MOSFET, the controller circuit adapted and configured to control the MOSFET to switch to a conducting state upon detection of an inverted supply polarity, wherein the control circuit is supplied by an energy storage device originally designed for operation with a non-inverted supply polarity.
A controller circuit comprising:
- a power supply input to be coupled to a power source;
- a control input;
- first and second outputs, each output to be coupled to a control terminal of a switch that couples a load to an energy source;
- and
- a control circuit coupled to the power supply input and the control input to generate first and second control signals at the first and second outputs respectively, wherein:
- the first and second control signals cause the switch to couple the load to the energy source in a normal operation mode when a signal received at the control input indicates that the load is to receive power and when the power source provides a normal supply potential to the power supply input;
- the first and second control signals cause the switch to decouple the load from the energy source when the signal received at the control input indicates that the load is not to receive power;
- and
- the first and second control signals cause the switch to conduct in a switch protection mode when the power source provides an inverted supply potential to the power supply input, the inverted supply potential having an opposite polarity than the normal supply potential.
Dependencies are inferred from the claim text.