ASFETs increase SOA while reducing PCB footprint
Application-specific MOSFETs (ASFETs) minimise derating and improve current sharing, says Nexperia.
ASFETs are MOSFETs optimised for use in particular design scenarios. The hot swap ASFETs use a combination of Nexperia’s silicon technology and copper clip package construction to significantly strengthen the SOA and minimise PCB area.
The new PSMN4R2-80YSE (80V, 4.2 mOhm) and PSMN4R8-100YSE (100V, 4.8 mOhm) hot-swap ASFETs are packaged in the Power-SO8 compatible LFPAK56E.
The ASFETs have enhanced safe operating area (SOA) performance, targeting hot swap and soft start applications in 5G telecomms systems and 48V server environments and industrial equipment needing e-fuse and battery protection.
Previously, MOSFETs have suffered from the Spirito effect, where the SOA performance drops off rapidly due to thermal instability at higher voltages. Nexperia’s enhanced SOA technology eliminates the “Spirito-knee”, increasing SOA by 166 per cent at 50V, compared to previous generations in D2PAK.
Mike Becker, senior international product marketing manager at Nexperia, said: “SOA is traditionally only specified at 25 degrees C, meaning designers have to derate for operation in hot environments. Our new hot-swap ASFETs include a 125 degrees C SOA specification, eliminating this time-consuming task”.
The internal copper-clip construction of the package improves thermal and electrical performance whilst reducing footprint size. The LFPAK56E package measures just 5.0 x 6.0 x 1.1mm – offering reductions of 80 and 75 per cent for PCB footprint and device height respectively, compared to the D2PAK of previous generations. The devices also feature a maximum junction temperature of 175 degrees C, meeting IPC9592 regulations for telecomms and industrial applications.
“A further benefit is improved current sharing in high power applications that demand multiple hot-swap MOSFETs to be used in parallel,” said Becker, the result, he added is improved reliability and reduced system cost.
The hot-swap ASFETs are fabricated at Nexperia’s new eight inch wafer production plant in Manchester, UK.