Patent ID: 7529070

Claim:
An integrated circuit including an electrostatic discharge circuit, the integrated circuit having at least two power supply rails, comprising: a first electrostatic discharge event detection circuit connected to a first power supply rail; a second electrostatic discharge event detection circuit connected to a second power supply rail; a first field effect transistor having a channel, said channel connected between said first power supply rail and said second power supply rail; a second field effect transistor having a channel, said channel connected between a gate of said first field effect transistor and one of said first power supply rail and said second power supply rail; at least one inverter stage having an output, said output connected to a gate of said second field effect transistor; and a gate control circuit operative to selectively connect the gate of said first field effect transistor to a common ground of said first power supply rail in response to the first power supply rail being at least equal to a transistor threshold voltage level and to selectively connect the gate of said first field effect transistor to a common ground of said second power supply rail in response to the second power supply rail being at least equal to the transistor threshold voltage level.