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May 25, 2024 - JECTRONIC INSTRUMENTS announces the launch of the CLIPPER CLP1500V15A1, an oscilloscope adapter that enables small-voltage measurements at very high voltages, such as the voltage across a switching MOSFET or IGBT (insulated-gate bipolar transistor). Previously, accurate measurements at very high voltages were extremely challenging, but with the CLIPPER CLP1500V15A1, the high-resolution switching characteristics of a transistor (e.g., 100mV/div) can now be easily viewed on an ordinary digital oscilloscope.
The CLIPPER CLP1500V15A1 greatly simplifies the determination of switching speed, safe operating area (SOA), and temperature effects for MOSFETs and SiC IGBTs. The CLIPPER CLP1500V15A1 represents a leap forward in transistor switching tests, which are critical both in design verification and in production process monitoring. In typical use, the CLIPPER is connected between the drain and source of a power MOSFET. The output signal provides a 1:1 image of what occurs across the MOSFET, free from interference by the high drain voltage. This allows the oscilloscope resolution to be reduced to 0.2V per division, providing an excellent view of the turn-on switching characteristics. In recent years, IGBT popularity has soared due to the increase in high-voltage, high-power applications at which IGBTs excel. Rated at currents up to 100 amps, IGBT modules are ideal for high-power applications such as PWM designs, electric vehicle and appliance motor drives, power factor correction converters, solar inverters, uninterruptible power supplies (UPS), induction heating cookers, and high-frequency welders. The CLIPPER directly measures the voltage between the drain and source (Vds) of a power transistor (MOSFET or IGBT). The output voltage measurement is limited to a safe range between 0 and 2V (low range) or 0 and 14V (high range). This allows the oscilloscope to be set to the appropriate full-scale range, with a sensitivity of 200mV or 2V per division. The resulting high-resolution Vds information can be used for indirect measurements such as:
Measuring Rds ON during operation (since the switching current is usually known).
Observing changes in RdsON during operation, indicating changes in thermal resistance (detecting inadequate heat dissipation or cooling).
Junction temperature - directly visualized based on RdsON.
Thermal stability - directly visible when the load changes dynamically
For thermal process monitoring, if RdsON is unstable (i.e., an unstable SOA), there is a reliability concern. This may be a catastrophic thermal runaway issue leading to shutdown, or a higher-than-expected junction temperature (Tj) that shortens transistor life. During product validation, design issues that cause SOA problems may include: incorrect load regulation, incorrect transistor selection, gate drive optimization issues, IGBT turn-on issues, or poor thermal design. These issues, as well as others caused by production process variations (such as solder quality, PCB thermal and heatsink conductivity, or cooling issues), can all benefit from using the CLIPPER. The CLIPPER is ideal for: production screening, 100% product evaluation, electrical and thermal design verification and qualification, repair and maintenance. The CLIPPER CLP1500V15A1 requires no calibration or external power supply, and comes in an attractive aluminum carrying case, along with various SMA and BNC adapters. The CLIPPER CLP1500V15A1 is manufactured by Springburo, a European custom power electronics designer, and is now available from its Chinese distributor JECTRONIC INSTRUMENTS.
About JECTRONIC INSTRUMENTS. Jectronic was founded in 2014 in Changsha, China, and is an instrument and test solutions provider in central China, with a reputation for finding and sourcing superior, unique test, measurement, and control products and components for a variety of industries. Its product line is continually expanding from around the world and is offered at competitive prices, accompanied by comprehensive in-house technical support, excellent customer service, and fast delivery.
