US Patent 7102865 Output driver having electrostatic discharge protection

An output driver having electrostatic discharge (ESD) protection is disclosed. The output driver includes a first gain transistor, a second gain transistor, a capacitor and a resistor. The first gain transistor provides a first stage gain, and the second gain transistor provides a second stage gain. The capacitor, which is connected to the first and second gain transistors, provides a compensation function between the first and second gain transistors during normal operations. In response to an occurrence of an ESD event at the output of the output driver, the capacitor turns on the second gain transistor The resistor, which is also connected to the first and second gain transistors, returns the second gain transistor to normal operations after the occurrence of an ESD event.