Driver circuit for circuit tester

A method for providing high-speed test signals to an electronic device under test in a driver circuit comprising a pre-driver stage with inputs and outputs, said inputs connected to control signals, said outputs comprising actuation signals, said pre-driver stage comprising an amplifier connected to first and second switching transistors, said driver circuit further comprising a driver stage which receives said actuation signals produced from said pre-driver stage and drives the test signals, said driver stage comprising first and second emitter follower transistors, said first emitter follower transistor coupled to said first switching transistor, said second emitter follower transistor coupled to said second switching transistor, comprising the steps of:

• providing control signals to said pre-driver stage, said control signals corresponding to a desired test signal;
• switching said first and second switching transistors on and off, in and out of saturation, respectively;
• switching said first and second emitter follower transistors on and off, outside of saturation;
• and
• driving said desired test signal to said electronic device under test.