POWER AND LINEAR IC SOLUTIONS

150V/200V MOSFETs Shrink Footprint and Improve Efficiency

Two new power MOSFETs from International Rectifier combine the company’s advanced DirectFET® packaging and HEXFET® MOSFET silicon technology to achieve high efficiency and high current operation from a wide input voltage range. The IRF6641TRPbF (200V) and IRF6643TRPbF (150V) devices serve a range of applications including isolated DC-DC and intermediate bus converters and synchronous rectification in AC-DC equipment that is powered from a 36V to 75V universal input voltage range.

The IRF6641TRPbF achieves a current rating of up to 26A with an extremely low typical 10V R_DS(on) of 51mΩ. Its reduced gate charge (Q_g) of 34nC and low package inductance cut both conduction and switching losses. The 35A IRF6643TRPbF exhibits an even lower typical 10V R_DS(on) of 29mΩ, with 39nC Q_g and 11nC Q_gd.



Both devices use a common MZ footprint allowing an easy migration path to other DirectFET® MOSFETs for higher current and lower voltage ratings. The package itself has the same footprint size as a low-profile SO-8, with a profile of just 0.7mm.

Patented DirectFET® packages feature a metal can construction that enables dual-side cooling, effectively doubling current-handling capacity. In addition, they are RoHS compliant. The board space saving alone of one DirectFET® MOSFET versus two or three SO-8 devices is more than 50%.

In comparisons of the in-circuit efficiency of the IRF6641TRPbF with other enhanced SO-8 devices in secondary-side synchronous rectification sockets, the device delivers a 0.4% efficiency improvement when the same numbers of enhanced SO-8 devices are used per socket. The new device provides the same 7A, full-load efficiency when the numbers of enhanced SO-8 devices are doubled-up at each socket. In this same analysis, the MOSFET temperatures are lowest in the circuit using two IRF6641TRPbF devices per socket.

Product Specifications

Part #	Package	BVDSS (V)	RDS(on) max @10V (mΩ)	RDS(on) typ @10V (mΩ)	VGS (V)	ID @ TC =25ºC (A)	QG typ (nC)	QGD typ (nC)
IRF6641TRPbF	DirectFET	200	59.9	51	20	26	34	9.5
IRF6643TRPbF	DirectFET Med. Can	150	34.5	29	20	35	39	11

Both the IRF6641TRPbF and IRF6643TRPbF are designed for use in isolated DC-DC converter architectures operating from a universal telecommunications input range (36V to 75V). They can also be used in synchronous rectifiers for the high current AC-DC converters used to power computers and telecom servers operating from a 48V supply. Other applications include as synchronous rectifier MOSFETs in high frequency, high efficiency DC-DC converters powering high current loads; the latest generation of intermediate bus converters; DC motor drives; and specialised environments such as the 48V inverters used to convert power from wind turbines.

Features

• High-current MOSFETs
• 150V/35A and 200V/26A options
• 36V to 75V input
• Low-profile (0.7mm) package with standard SO-8 footprint
• Low R_DS(ON)
  • 51mΩ (IRF6643TRPbF)
  • 29mΩ (IRF6641TRPBF)
• Low gate charge
  • 39nC Q_g/11nC Q_gd (IRF6643TRPbF)
  • 34nC Q_g/9.5nC Q_gd (IRF6641TRPbF)
• Dual-sided cooling effectively doubles current-handling capability
• RoHS compliant

Applications

• Isolated universal-input (36V to 75V) DC-DC converters
• Synchronous rectifiers for high current 48V AC-DC converters
• High frequency, high efficiency DC-DC converters
• Intermediate bus converters
• DC motor drives
• Wind turbines

For further information, including the IRF6641TRPbF and IRF6643TRPbF Datasheets and Product Briefs, please click here.