Abstract: A special purpose pulse amplifier with programmable high and low levels for complex IC testing is disclosed. Its output has independently programmable positive and negative transition rates and is reverse terminated in 50 ohms. It also has the ability to be switched to a high resistance, low capacitance output state. This circuit is the interface between a complex, computer controlled system of timing and pattern generation hardware, and an integrated circuit to be tested. This device has reduced waveform aberrations, lower inhibited capacitance, low input to output delay for reducing timing error, programmable signal transition rates, and the amplitude range and transition rate control to accommodate all the important device technologies expected in high pin-count parts.

Abstract: Disclosed herein is a circuit for protecting an inhibitable tristate data driver from damage due to an over current. A logic comparator circuit compares input and output logic levels of the data driver, and inhibits the driver causing the output to go to a tristate if a fault occurs.