Nowadays, with the growth of mobile devices, laptops and tablets, the demand for low-voltage power adapters is unprecedented.
In fact, according to Dr. J. Christopher Dries, President and CEO of UnitedSiC, there are more than 300 million low-voltage chargers on the market, each of which contains a flyback converter.
Because these devices rely heavily on power conversion, designers have been working to improve efficiency and reduce the conversion loss caused by traditional switching circuits.
At present, the low-voltage charger market is still dominated by silicon materials, and has lasted for decades.
"Silicon technology still dominates the market. If we want to improve efficiency seriously, we need to reduce the heat loss of these devices." Aly Mashaly, power system manager of ROHM Semiconductor Europe, explains.
"In the past, if you had your laptop turned on for a few hours, it would be very hot. Today we see a significant improvement in the efficiency of electronic devices. However, as equipment becomes more and more power-intensive, it is also necessary to improve the efficiency of low-voltage adapters.
"At present, low-voltage adapters are mainly driven by MOSFET." "It's a cost-effective solution because consumers don't want to spend a lot of money on cell phone chargers," Dr. Dries said. But people also hope to improve efficiency, especially in terms of size and weight.
To facilitate this process, UnitedSiC is developing a SiC product that it believes can compete with similar products and have cost advantages.
"Many silicon carbide companies are focusing on high-power markets, such as 600V and above product markets, such as car charging piles and so on." Dr Dries explained. "But we see opportunities to bring SiC technology into the low-power market. In fact, no one has done this. We let people spend a little more money, but achieve significant performance improvements in terms of efficiency and frequency.
Its SiC JFET chip can be packaged together with low voltage MOSFET and controller. Dr. Dries said this would create a very fast, 20-100W flyback product based on cascode, which would save a lot of space and have an efficient flyback power topology.
These normally open SiC JFETs range from 650V to 1700V. They can simplify start-up and zero standby power consumption. They are suitable for flyback AC-DC applications, including consumer adapters.