Dynamic pin driver combining high voltage mode and high speed mode

Abstract

A driver circuit for automatic test equipment provides high voltage range and high frequency. The driver circuit includes a voltage buffer that has high voltage swing and is capable of dynamically generating an output voltage that alternates between two statically established voltage levels. The driver circuit also includes a current buffer that has high speed and is capable of dynamically generating an output current that alternates between two statically established current levels. The voltage buffer and the current buffer each have an output, and the output of the voltage buffer is coupled to the output of the current buffer through a series impedance. The output of the current buffer is also coupled to a device under test (DUT). A control circuit directs the voltage buffer and the current buffer to generate either static or dynamic output signals. If it is desired to generate an output signal having high voltage swing, the control signal operates the current buffer statically and operates the voltage buffer dynamically. If, however, high frequency is desired, the control circuit operates voltage buffer statically and the current buffer dynamically. Thus, the advantages of both the voltage buffer and the current buffer are achieved in a single driver circuit.