Get to market faster with your SiC and GaN based design
•Are your GaN HEMTs and SiC MOSFETs blowing up?
•Are faster switching speeds on your power devices causing ringing and shootthroughs that you cannot debug?
•Are you having trouble optimizing gate drive performance and deadtime on your half-bridge circuits?
•Are you having trouble making GaN HEMT or SiC MOSFET perform just right?
•Are you having trouble getting the promised efficiency performance from your fast switching power converter?
The power electronics industry has relied on silicon-based MOSFETs and IGBTs for most of their power switching needs since the 1980s. Although these are well understood and reliable technologies, silicon technology is reaching its limits because of increasing efficiency and power density demands from industries such as automotive, data-centers, renewable systems, consumer electronics, and industrial power electronics.
After years of research and design, SiC (Silicon Carbide) and GaN (Gallium Nitride) power devices from companies such as Wolfspeed, EPC, GaN Systems, Rohm, Infineon, Semikron, Transphorm, and ST are becoming more viable. SiC, with its capability of driving high power at high voltages for high power applications, and GaN, with its super high-power density for medium to low power applications, are pushing the limits of what is possible with silicon-based designs in efficiency and power density.
SiC has found its place in applications like PV inverters and high performance motor drives for automotive power trains and locomotives. GaN is carving its niche in data-center power, wireless power, consumer power supplies, and automotive and military/government power electronics.
These devices, though high performance, come with challenges for designers. Setting cost and reliability aside, these power devices are not drop-in replacements for their silicon counterparts.
Some of the biggest challenges working with SiC and GaN devices are the gate drive requirements. SiC requires much higher gate voltage (Vgs) with a negative bias for turn off. GaN, on the other hand, has much lower threshold voltage (Vth), requiring tight gate drive designs. Wide band gap (WBG) devices, by the nature of their physics, also have a higher body diode voltage drop which requires much tighter control of dead-time and turn-on/turn-off transitions. To gain real benefits from these devices, they need to be switched quite fast which requires tight parasitic controls on the layout. These “power” designs are acting like “RF” designs, so due diligence is required to optimize these designs.
Solving these challenges is tough for engineers. More important is accurate visibility into all these signals so that the right design decisions can be made in a timely fashion. Increasing design margins and overdesigning will only drive costs up and bring performance down. Using the right measurement equipment then makes all the difference.
Reacting to the challenges faced by engineers working on these challenges, Tektronix is introducing the SiC MOSFET and GaN FET Switching Power Converter Analysis Kit, the only solution in the market that accurately characterizes most critical parameters for optimizing power electronics topologies that use technology like SiC, GaN or any other fast switching silicon power devices.
The kit provides everything required to accurately test gate drive timing, gate drive performance, Vgs, Vds, Id, and turn-on/turn-off on both high and low side power switches. Accurate characterization of high-side and low-side switches simultaneously also enables precise dead-time optimization to get the best performance out of these designs. Additionally, it comes with powerful 5PWR software which enables testing switching losses, conduction losses, magnetic losses, input and output power quality measurements, and overall power efficiency.
What’s in the kit?
•5PWR Software: Advanced power analysis software
•TIVH08: (2.5KV, 800MHz) High voltage isolated differential probes
•TIVH05 (Optional): (2.5KV, 500MHz) High voltage isolated differential probes
•TIVM1 (Optional): (50V, 1GHz) High BW isolated differential probes
•TPP1000 (Free): (1GHz) High BW passive probe (standard with scope)
•MMCX Tip for TPP1000 (Optional): Tip for high BW performance
•GaN Half-bridge Demo Board Instruction Guide: Getting Started Guide using GaN Half-bridge demo board
Is this kit designed only for SiC or GaN based power designs? What about silicon-based MOSFETs and IGBTs?
•This kit is designed for all power converters/inverters that use fast switching power devices. SiC and GaN technologies are generally the fastest switching power devices and will benefit most from this kit.
You mentioned “Fast Switching.” What does that mean? How do I know what bandwidth to pick?
•Fast switching refers to the turn-on/turn-off transitions of a power device and not the switching frequencies of the design.
•It’s important to know how fast your power switches are going to transition to determine the bandwidth you need on your test setup. Switching frequency is not a good measure for selecting bandwidth specifications on probes and scopes.
•Most GaN devices in the market have turn-on/turn-off time below 10nS. These fast switching times can result in ringing and aberrations at 100Mhz or higher frequencies. If your converter switches at 100s of kHz, the probes and scopes you would need to design would far exceed 100MHz.