Patent ID: 7639468

Claim:
A circuit for measuring, limiting and switching a load current on a load, comprising: a first supply line; a current mirror with a double transistor, a first resistor and a second resistor, which result in a mirrored measurement current according to the condition I M I L = R ⁢ ⁢ 1 R ⁢ ⁢ 2 ; a switching transistor to control the double transistor; a measuring resistor, wherein a measurement voltage proportional to the measurement current dropping at the measuring resistor is electrically connected between the double transistor and a second supply line of the load; a control electrode of the switching transistor electrically connected to the first supply line via a fourth resistor and a transistor connected in parallel to the fourth resistor; and a fifth resistor to apply a switching voltage, wherein the fifth resistor is electrically connected to the control electrode of the switching transistor, and wherein the control electrode of the transistor is electrically connected to the double transistor at a link of the first resistor.