Abstract: A generator provides a repetitive pattern which is applied to the input of a DUT and to the input of a timing generator. The output of the DUT follows the pattern at the input, switching the voltage between two levels. The High Frequency Voltage Sampler measures instantaneous voltage levels on the output waveform of the DUT. The timing generator uses the input signal to generate enable signals for the High Frequency Voltage Sampler which are synchronized to the test waveform and which can be time-delayed in precise intervals and with good repeatability. By placing this signal at a desired point anywhere along the test waveform the voltage at this point can be measured by the High Frequency Voltage Sampler. The High Frequency Voltage Sampler uses the leading edge of the enable signal to start the measurement of the instantaneous voltage level and it uses the trailing edge to store this level.

Abstract: A supporting plate holds a test device and is moved so that the pins of the device are electrically connected to a plurality of contact springs further connected to selected signal sources mounted on input and output boards. This approach avoids both using contact plates and an unduly long contact path between the test device and board, thereby minimizing parasitic inductance and capacitance. This provides improved test results for the devices tested and increased accuracy over well known types of sockets. The test socket design allows easy repair, maintenance and use which greatly increases test productivity and reliability.