June/July 2021

24 POWER SEMICONDUCTORS www.infineon.com/coolsic-mosfet-discretes Issue 3 2021 Power Electronics Europe www.power-mag.com switching frequency. Here there are significant efficiency gains to be had, along with a reduction in size and cost of associated components, particularly magnetics. This can result in significant end-product savings in cost, size and weight, as well as lower energy bills. In bi- directional converters, SiC devices can perform all high voltage switching functions with higher efficiency than traditional solutions and with their superior body diode characteristics, can make hard switching topologies such as the totem- pole PFC viable and cost effective. Infineon offers a range of CoolSiC™ MOSFETs in discrete and module formats in ratings from 650 V to 1700 V and with on-resistance down to 2 milliohms. The devices are further complemented by a range of EiceDRIVERTM gate drivers in non-isolated and isolated variants for low- and high-side drives, using Infineon’s coreless transformer technology. For a complete solution, current sensing ICs and microcontrollers for digital control are also available. Literature [1] 3300 W CCM bi-directional totem pole with 650 V CoolSiC™ and XMC™ Infineon application note AN_1911_PL52_1912_141352 Infineon has showcased a 3.3 kW totem- pole PFC stage (EVAL_3K3W_TP_PFC_SIC) [1] which achieves 73 W/in 3 (4.7 W/cm 3 ) power density with a peak efficiency of 99.1 % at 230 VAC input and 400 VDC output (Figure 4). Efficiency also peaks at over 98.8 % when operating in inverter mode, generating 230 VAC at 50 Hz. The evaluation board features full digital control, implemented with the Infineon XMCTM series microcontroller. Conclusion SiC MOSFETs are a natural evolution from Si superjunction MOSFETs for applications at medium to high power with high Figure 4: A high- efficiency bi-directional AC/DC- DC/AC converter using CoolSiC MOSFET technology