Device for protecting a semiconductor circuit

摘要

A protection device for protecting a semiconductor circuit from positive and negative overvoltage such as static electrical discharges. A p-type substrate is provided having a pair of spaced apart n-type regions formed therein. Each of the spaced apart n-type regions has a p+ region and an n+ region formed therein. Each of the spaced apart n-type regions also includes an n+ drain tap which has a portion in contact with the substrate. The n+ region and one p+ region of one of the spaced apart n-type regions are connected to a terminal of a semiconductor circuit. The n+ region and p+ regions of the other n-type region are connected to a power voltage of the semiconductor device. A insulated gate is formed on a p-type semiconductor substrate, and is in contact with both n+ drain taps. The gate is grounded. The bilateral protection device of the present invention protects the semiconductor circuit against positive and negative overvoltages.