Patent ID: 7978453
Filing Date: 2011-07-12
Classification: H03K

Abstract:
1. A driver circuit for conducting current through an electronic device connected to a supply voltage source comprising: a driver module including a first transistor for connecting to a driver voltage source for receiving a driver voltage signal and for conducting current from the supply voltage source through the electronic device and through said first transistor in response to receiving said driver voltage signal; a protection module including a second transistor in electrical communication with said first transistor for receiving a voltage signal and for inhibiting current flow through said first transistor in response to receiving the voltage signal; said protection module including a digital logic gate having at least one input in electrical communication with said first transistor for receiving a short-circuit voltage signal equal to the supply voltage from the supply voltage source and having at least one output for outputting a logic voltage signal, in response to receiving said short-circuit voltage signal, to said second transistor; wherein said first transistor is a field effect transistor having a gate terminal for connecting to the driver voltage source to receive said driver voltage signal and having a drain terminal for connecting to the electronic device and having a source terminal in electrical communication with a ground reference for conducting current from the electronic device through said drain terminal to said source terminal in response to said gate terminal receiving said driver voltage signal; wherein said second transistor is a bipolar junction transistor having a base terminal for receiving a logic voltage signal and having a collector terminal in electrical communication with said gate terminal of said field effect transistor and having an emitter terminal in electrical communication with a ground reference for conducting current from said gate terminal of said field effect transistor through said collector terminal to said emitter terminal in response to receiving said logic voltage signal for inhibiting current flow through said field effect transistor; a pull-down resistor having a first end in electrical communication with said base terminal of said bipolar junction transistor and having a second end in direct electrical communication with a ground reference; wherein said digital logic gate is an AND gate having a first input in electrical communication with said first transistor for detecting said short-circuit voltage signal and having a second input for being connected to the driver voltage source for receiving said driver voltage signal and having an output for outputting said logic voltage signal to said second transistor in response to simultaneously receiving said short-circuit voltage signal and said driver voltage signal; wherein said first input of said AND gate is in electrical communication with said gate terminal of said field effect transistor for receiving said driver voltage signal and said second input is in electrical communication with said drain terminal of said field effect transistor and said output for outputting said logic voltage signal in response to simultaneously receiving both of said short-circuit voltage signal and said driver voltage signal; a gate resistor having a first end in electrical communication with said first input of said AND gate and having a second end in electrical communication with said gate terminal of said field effect transistor and said collector terminal of said bipolar junction transistor; and a first logic resistor having a first end in electrical communication with said first input of said AND gate and having a second end in electrical communication with said first end of said gate resistor.