Tektronix accelerates SiC and GaN validation
As wide bandgap switching devices are increasingly incorporated into electric vehicles, solar energy and industrial controls, Tektronix has made a time entry to the market with an oscilloscope-based double pulse test suite which speeds up validation time on SiC and GaN technologies, said the company.
The wide bandgap double pulse test (WBG-DPT) suite has the ability to provide automated, repeatable, and accurate measurements on wide bandgap devices such as SiC and GaN MOSFETs.
Designers of next-generation power converters will be able to utilise it to optimise designs confidently and quickly, claimed Tektronix. It can run on Tektronix 4, 5 and 6 Series mixed signal oscilloscopes (MSOs), integrating seamlessly into the measurement system of scopes and boasts several industry-first measurement capabilities, such as an automatic WBG deskew technique, and reverse recovery timing plots, making it easier for engineers to see reverse recovery details for multiple pulses overlaid on a single display. Measurements are also designed to align with JEDEC and IEC standards for double pulse testing and diode reverse recovery.
The deskew technique eliminates the need for rewiring and may even be performed after double pulse measurements have been taken. Tektronix claimed this is an industry first and is used to simulate the effects of delays in the test set up. The software generates an alignment waveform and an engineer adjusts settings to match this with the measured waveform; the software corrects any differences in delays. This process reduces the deskew time from an hour or more to just five to 10 minutes, said Tektronix.
Daryl Ellis, Tektronix’s mainstream portfolio general manager, said the design of the WBG-DPT suite will allow for simplified debugging, repeatable measurements and a faster learning curve. “Test automation reduces test times and retesting errors, ensuring our customers meet their project timelines and time to market plans,” he added.
“The WBG-DPT software provides instantaneous measurements of key parameters, like EON, EOFF, and QRR when performing double-pulse tests,” said Masashi Nogawa, staff systems engineer at semiconductor provider, Qorvo. “The software makes the power waveform and markers showing the integration ranges used to calculate the energy losses immediately visible. This is an excellent alternative to exporting waveform data into Excel spreadsheets for processing.”
To achieve meaningful energy loss measurements, designers must correct for delays introduced by test fixtures and probes. The traditional technique for aligning drain-to-source- voltage (VDS) and drain current (ID) measurements requires rewiring the test setup and careful pre-test measurements.
Since power converters must operate over a wide range of temperature conditions, there is a growing need to measure output charge (QOSS) at different junction temperatures. The Tektronix WBG-DPT boasts fast and accurate QOSS measurements, providing important insight into the effects of device output capacitance.
Another industry first, claimed Tektronix is the reverse recovery timing plots which make it easy for engineers to see reverse recovery details for multiple pulses overlaid on a single display. Measurements are made per JEDEC and IEC standards, and users can configure measurements in WBG to query results on every first or second pulse, or all pulses of a double pulse set. This approach to reverse recovery plotting allows for multiple double pulse sets and provides visual and measurement results on each set. It is possible to zoom in on the reverse recovery region and even debug reverse recovery parameters of the system.
