2.2 Use of Double Pulse Generation Circuit

The ASD2-EVAL-001 Evaluation Board is provided with a double pulse generation circuit, as shown in the following figure. It consists of a switch (SW1) and three preset multi-turn potentiometers. By pressing switch SW1 once, a double pulse waveform is generated. Connect an external switch at connector J11 to generate a double-pulse waveform. POT R85 is used to set/change the pulse width of the first pulse, POT R96 is used to set/change the delay between the first and second pulse, and POT R97 is used to set/change the pulse width of the second pulse.

Verify the pulse widths before further high voltage characterization of SiC devices (MOSFET). This can be verified by examining the signal generated on pin 3 of the connectors J9 and J10 using the oscilloscope.

To characterize the High-Side device, place the jumper on pin 2 and pin 3 of the connector J9, and to characterize the Low‑Side device, place the jumper on pin 2 and pin 3 of the connector J10. In double pulse mode, only one device must be characterized at a time.

The minimum adjustable pulse width for the first and second pulse is 1 μs, and the minimum adjustable delay set between both the pulses is approximately 4 μs. See the following figure for more information.

The maximum pulse width for the first and second pulse is 24 us, and the minimum delay set between both the pulses is approximately 6.5 μs. See the following figure for more information.