The measurement instrument SML 726 to investigate into the blocking characteristics of power semiconductors. A peak voltage of -8,000 V at a current of up to 100 mA is available.

The device is designed for integration in an automated measuring system and offers a serial interface as well as Ethernet and optical fibre interfaces. There are no manual controls.

The blocking voltage is adjustable in a range from -30 to -8,000 V. The current limit is defined by the resistor RSHUNT and is adjustable from 10 µA to 100 mA.

The SML 726 offers two operating modes:

1. Blocking voltage measurement: The test voltage will be increased until either the maximum output current (10 μA to 300 mA) or the maximum adjusted voltage is reached. The measurement result is determined during the integration period at the end of the measurement duration.
2. Reverse current measurement: The current through the specimen at nominal voltage is measured. Thereby the measurement duration is defined by the parameter “test duration”. The measurement result is also determined during the integration period at the end of the measurement duration.

A deviation of achieved voltage from nominal voltage leads to an error message.