Nexperia is claiming to have squeezed a 40V mosfet with 0.7mΩ Rds(on) into 8 x 8mm, using its LFPAK88 package and its latest (Trench9) silicon – intending to displace D²PAK and D²PAK-7 devices – saving 60% of footprint and with a 64% lower profile.
“Unlike packages where performance is often limited by internal bond wires, LFPAK88 devices employ copper-clip and solder die attach construction, resulting in low electrical and thermal resistance, good current spreading and heat dispersal,” said Nexperia. “In addition, the thermal mass of the copper-clip also reduces hot-spot formation which results in improved avalanche energy and linear-mode safe-operating-area performance.”
Clip inductance is 1nH and the firm is claiming continuous 425A drain current is possible through the 0.7mΩ device – which it calculates to be 48 times better power density when compared with D2PAK devices (calculations sadly not provided).
Credit to to Nexperia for declaring the maximum Rds(on) for the PSMNR70-40SSH – the 0.7mΩ figure. Typical is 0.62mΩ (at gate=10V, 25A, junction=25°C).
There are currently 0.7, 0.9 and 1mΩ devices – with or without NextPowerS3, which is some sort of diode structure which has “high efficiency and low spiking performance usually associated with mosfets with an integrated Schottky or Schottky-like diode, but without problematic high leakage current”, according to Nexperia.
Leads are gull-wing for low-stress, and Nexperia is claiming “reliability levels more than two times better than is required by AEC-Q101”.
LFPAK88 mosfets are available in automotive-qualified (BUK) and industrial (PSMN) grades. Applications in braking, power steering, reverse battery protection and DC-DC converters are expected in automotive, where the small size could help where dual redundancy is required. Away from cars, battery-powered power tools, professional power supply and telecoms infrastructure use is foreseen.
