Power MOSFET with overcurrent and over-temperature protection

A MOSgated semiconductor power device having a fault condition responsive control circuit integrated into the same die which contains a power section for said device;

• said device comprising a semiconductor die having first and second main electrodes and a gate electrode for controlling the conduction of current between said first and second main electrodes;
• said device having at least first, second and third connection pins;
• said first and second pins connected to said first and second main electrodes respectively;
• said fault condition responsive control circuit being formed in at least one separate well area within said semiconductor die;
• said fault condition responsive control circuit being operable to turn off a signal to said gate electrode in response to a predetermined fault condition;
• said fault condition responsive control circuit having an input terminal for a control voltage V.sub.cc needed for the biasing and operation of the components of said fault condition responsive control circuit;
• a first control MOSFET connected between said third connection pin and said gate electrode and a second control MOSFET connected between said gate electrode and one of said first and second main electrodes;
• said input terminal of said fault condition responsive control circuit being connected to the voltage at the node between said third pin and said first control MOSFET;
• said first control MOSFET being turned on and said second control MOSFET being turned off during the time that said MOSgated semiconductor power device is in normal conduction;
• said fault condition responsive control circuit being operable to turn off said first control MOSFET and turn on said second control MOSFET in response to a monitored fault condition.