Overcurrent detection circuit for a power MOSFET and method therefor

An overcurrent detector circuit for detecting when a predetermined current of a power Metal Oxide Semiconductor Field Effect Transistor (MOSFET) is exceeded, the overcurrent detector circuit having an input and an output, the power MOSFET having a drain coupled to the input of the overcurrent detector circuit, a gate coupled for receiving a control signal, and a source coupled for receiving a first power supply voltage, the overcurrent detector circuit comprising:

• a first transistor of a first conductivity type having a first electrode and a control electrode coupled in common, and a second electrode coupled to the input of the overcurrent detector circuit;
• a first diode having a first electrode and a second electrode coupled to said first electrode of said first transistor;
• a first current source having a first terminal coupled for receiving a second power supply voltage and a second terminal coupled to said first electrode of said first diode;
• a second transistor of said first conductivity type having a first electrode, a control electrode coupled to said first electrode of said first diode, and a second electrode;
• a second diode having a first electrode coupled to said second electrode of said second transistor and a second electrode;
• a resistor having a first terminal coupled to said second electrode of said second diode and a second terminal coupled for receiving said first power supply voltage;
• a second current source having a first terminal coupled for receiving said second power supply voltage and a second terminal coupled to said first electrode of said second transistor;
• a third transistor of a second conductivity type having a first electrode coupled to the output of the overcurrent detector circuit, a control electrode coupled to said first electrode of said second transistor, and a second electrode coupled for receiving said second power supply voltage;
• and
• a third current source having a first terminal coupled to said first electrode of said third transistor and a second terminal coupled for receiving said first power supply voltage.