ROHM Debuts Three IGBTs with Built-In SiC Schottky Barrier Diodes (SBD)
The new devices utilize ROHM’s Schottky SBDs as a freewheeling diode to effect minimal switching power losses
The new RGWxx65C series feature withstand voltages of 650V and handle currents of up to 50 amps. Their internal low-loss Silicon Carbide (SiC) SBDs feature almost no recovery energy, resulting in minimal diode switching losses.
The RGWxx65C. Image courtesy of ROHM
Since the IGBT won’t have to deal with the recovery charge in its turn-on mode, losses here too are reduced. When the units are employed in-vehicle charging applications, these beneficial effects combine to produce a 24% power loss reduction when compared to Super Junction (SJ) MOSFETs and a 67% savings over conventional IGBTs.
Insulated Gate Bipolar Transistors (IGBT) are cheaper to produce than Super Junction (SJ) MOSFETs are. But, they exhibit power losses when being switched on or off, and they require a freewheeling diode to ameliorate the problem, often in the form of a separate chip. SJ MOSFETs, on the other hand, have internal body diodes just by the nature of their structure, but the MOSFETs have limitations in the power they can handle.
A Hybrid IGBT (center) features a built-in silicon carbide Schottky Barrier Diode. Image courtesy of ROHM
Hybrid IGBTs incorporate an internal freewheeling diode, so the high-power devices exhibit minimal switching losses. In addition, SiC SSDs like those of the RGWxx65C series’ offer better performance than conventional silicon freewheeling diodes.
With these advantages, members of the RGWxxT65 series offer efficiencies of over 97% over a wide operating frequency range when employed in automotive chargers. That’s a full 3% higher than existing IGBTs at 100kHz.
The Members of the Series
ROHM now offers the RGW60TS65CHR, the RGW80TS65CHR, and the RGW00TS65CHR, which can handle collector currents of 30, 40, and 50 amps, respectively. In the same order, the units feature power dissipation (Pd) capacities of 178W, 214W, and 254W at 25℃. Beyond that temperature, Pd’s derate linearly down to zero at 175℃.
The three units all feature the following maximums:
- Collector cutoff currents of 5mA
- Gate-emitter leakage currents of ±200nA
- Gate - emitter threshold voltages of 7.0V
- Collector - emitter saturation voltages of 1.9V
The units exhibit the following typical characteristics:
The RGW40NL65CHRB, RGW50NL65CHRB and the RGW60NL65CHRB are under development. These later devices will also utilize internal SIC SBD freewheeling diodes, but will handle somewhat less current.
These units are aimed at industrial as well as automotive applications that involve high power, such as:
- EV applications
- Photovoltaic power conditioners
- Power factor correction (PFC)
- Industrial Inverters
- On-board and off-board chargers
- DC/DC converters
The units are available in TO-247N packages
The operating junction temperature range is from -40 to +175℃
Members of the RGWxxT65 series are AEC-Q101 qualified
Getting to Market Faster
ROHM advises that they provide a range of design support materials that are available on the company’s website. These aides include notes on drive circuit design, application notes and, most importantly, spice models.