Power FETs Cut Losses For 3.3V Output Bricks

Efficiencies of the primary and secondary sections of isolated dc-to-dc converters with 3.3V outputs are said to be significantly improved by two new families of HEXFET power MOSFETs. In existing 3.3V-output 200W converter bricks, for example, the new HEXFETs reportedly can cut losses by >25% with only minimal converter design changes required. Lower power converters can also benefit from the new FETs.
The primary FETs of forward converters are built using a new planar technology as it reportedly gives the best trade-off between switching and conduction losses. They offer a B_VDSS of 200V or 150V, a V_gs of 30V, and a R_DS(on) of from 45 to 235 milliohms. And prices start at $0.46 each/10,000.
On a forward converter's secondary side, FET choice depends on the overall switching topology, with different optimization techniques controlling cost/efficiency trade-offs. These HEXFETs offer a B_VDSS of 20V or 30V, a V_gs of 12V or 16V, and a R_DS(on) of 2.5 to 8 milliohms. Prices start at $0.55 each.