Malvern, Pa.Vishay Intertechnology Inc. has expanded its Gen III TrenchFET power MOSFET line with the release of two 20-V and two 30-V n-channel devices that will be used as the high-side MOSFET in synchronous buck converters, helping to save power in notebook computers, voltage regulator modules (VRMs), servers, and other systems using point-of-load (POL) power conversion.
These MOSFETs are the first to offer TurboFET technology, which uses a new charge balanced drain structure to lower the gate charge by up to 45%, according to Vishay. As a result, they achieve lower switching losses and faster switching.
The 20-V SiS426DN device offers what the company claims is the industry's lowest on-resistance time gate charge for a device with this voltage rating in the 3-mm by 3-mm PowerPAK 1212-8 footprint. This key figure of merit (FOM) for MOSFETs in dc-to-dc converters is 76.6 milliohms-nC at 4.5 V and 117.60 milliohms-nC at 10 V for the SiS426DN, which features a low typical gate charge of 13.2 nC at a 4.5-V gate drive and 28 nC at a 10-V gate drive.
Compared to the closest competing devices, these specifications represent a reduction in gate charge of 45% at 4.5 V and 36% at 10 V, and a 50% lower FOM, Vishay said. Lower gate charge translates into more efficient switching at all frequencies, and in particular gives the designer the option to operate at higher frequencies, which enables the use of smaller passive components in dc-to-dc converters.
Vishay's 30-V TurboFET offering includes the new Si7718DN in the PowerPAK 1212-8, and the Si7784DP in the PowerPAK SO-8. Both MOSFETs offer typical gate charge of 13.7 nC at 4.5 V and 30 nC at 10 V, and on-resistance times gate charge FOMs of 112.34 milliohms-nC at 4.5 V and 180 milliohms-nC at 10 V. A PowerPAK SO-8 version of the 20-V SiS426DN device, the SiR496DP, is also available for high-current applications. All devices released today are halogen free and 100 % Rg and UIS tested.
Vishay Intertechnology, www.vishay.com