Patent ID: 8885309

Claim:
A voltage transient protection system comprising: undervoltage protection circuitry coupled in parallel with electronic circuitry configured to receive a supply voltage from a power supply, said undervoltage protection circuitry being configured to shunt undervoltage current resulting from an undervoltage transient in said supply voltage away from said electronic circuitry, said undervoltage protection circuitry comprising: control circuitry including a first transistor, a second transistor and a resistor; and voltage transient shunt circuitry including a switching device coupled to said control circuitry; said first transistor being coupled between a ground potential and a gate of said switching device through said resistor with a gate of said first transistor coupled to said power supply, said second transistor being coupled between said power supply and said gate of said switching device through said resistor with a gate of said second transistor being coupled to said ground potential, said switching device having a bulk terminal coupled to the sources of said first and second transistors; said control circuitry being configured to change a conduction state of said voltage transient shunt circuitry in response to said undervoltage transient to shunt said undervoltage current away from said electronic circuitry.