Overcurrent protection device and method of operating a power switch

摘要

An overcurrent protection device comprises a maximum-allowed-current unit and a power switch. The maximum-allowed-current unit determines a maximum allowed current in real-time. The maximum allowed current is determined at least partially on an instantaneous level of a load voltage. The load voltage is a voltage across a load to be powered. The power switch is connectable with a switch input to a voltage supply and with a switch output to the load, for providing power to said load. The power switch has a conductive state and a nonconductive state, and is arranged to assume the nonconductive state in response to an indication that a current through the power switch is exceeding the maximum allowed current. A method of operating a power switch is also described.

主权项

1. An overcurrent protection device, comprising:
a maximum-allowed-current unit configured to determine a maximum allowed current in real-time, wherein said maximum allowed current is determined based on a selected one of a plurality of maximum allowed current profiles stored in a memory, and wherein the selected maximum allowed current profile is based on an instantaneous level of a supply voltage, and said supply voltage is a voltage across the overcurrent protection device and a load to be powered; and a power switch connectable with a switch input to a voltage supply and with a switch output to said load, and configured to provide power to said load, wherein said power switch has a conductive state and a nonconductive state, and the power switch is arranged to assume the nonconductive state in response to an indication that a current through the power switch is exceeding the maximum allowed current; and a turn-on detector to communicate with the power switch, the turn-on detector to detect a turn-on event for the power switch in response to a first edge of a pulse width modulation control signal, to trigger a first edge of a turn-on detection signal in response to the first edge of the pulse width modulation control signal, and to trigger a second edge in the turn-on detection signal in response to a second edge of the pulse width modulation control signal with a particular amount of delay from the first edge of the pulse width modulation control signal being detected.