Laptop ac/dc adaptor ref design uses GaN to boost power density
The reference design occupies 3.19 cubic inches (0.92 x 1.45 x 2.39 in., or 23.4 x 36.8 x 60.7 mm) and provides 65W of power at greater than 94% efficiency over the entire input voltage range (90 Vac – 264 Vac). At the core of this adapter is a synchronous rectifier circuit using 150V, 7 mOhm EPC2033 eGaN FETs from EPC.
EPC presents these GaN FETs as providing an 80% reduction in driving power, with a 25% reduction in on resistance. This enables a 5% reduction in power dissipation in the adaptor design due to the use of GaN FETs as synchronous rectifiers, and 9.5% less power dissipation using GaN devices as the primary switch.
According to Ionel “Dan” Jitaru, founder and President of Rompower, “We are quite proud to have made this breakthrough in size and performance for such an important product, the AC/DC adaptor. With its small size, it will ease the burden of users having to carry a large, clumsy adapter, while enjoying its energy savings and high efficiency.”