Patent ID: 7675726
Filing Date: 2010-03-09
Classification: H02H,H05K

Abstract:
1. A device for protecting an electronic module disposed in a control device in a multi-voltage on-board electrical system having an accumulator with a low on-board electrical system voltage against short circuiting to a high on-board electrical system voltage, comprising: a MOSFET transistor having a drain source path inserted between a control device connection and a connection of the electronic module, and with: a Zener diode connected between said gate and said source of said MOSFET transistor; a gate resistor connected between said gate of said MOSFET transistor and a positive pole of the first accumulator; and a diode connected in parallel with said gate resistor, for conducting current in a direction from said gate to the positive pole of the accumulator; wherein when a short circuit to the high on board electrical system voltage is conducted to said drain, said MOSFET transistor turns on or remains turned on; and wherein said MOSFET transistor has a threshold voltage and, in an event of a short circuit to a highest voltage of the on-board electrical system active at the device connection, a source voltage of said transistor is limited to a value Vs=Vbat