Datasheet

www.irf.com 1
11/14/07
DirectFET Power MOSFET 
DirectFET ISOMETRIC
MZ
PD - 97262A
Applicable DirectFET Outline and Substrate Outline (see p.7,8 for details)
Fig 1. Typical On-Resistance vs. Gate Voltage
Typical values (unless otherwise specified)
Description
The IRF6641PbF combines the latest HEXFET® Power MOSFET Silicon technology with the advanced DirectFET
TM
packaging
to achieve the lowest on-state resistance in a package that has the footprint of a SO-8 and only 0.7 mm profile. The DirectFET
package is compatible with existing layout geometries used in power applications, PCB assembly equipment and vapor phase,
infra-red or convection soldering techniques, when application note AN-1035 is followed regarding the manufacturing methods
and processes. The DirectFET package allows dual sided cooling to maximize thermal transfer in power systems, improving
previous best thermal resistance by 80%.
The IRF6641PbF is optimized for primary side sockets in forward and push-pull isolated DC-DC topologies, for wide range 36V-
75V input voltage range systems. The reduced total losses in the device coupled with the high level of thermal performance
enables high efficiency and low temperatures, which are key for system reliability improvements, and makes this device ideal
for high performance isolated DC-DC converters.
 Click on this section to link to the appropriate technical paper.
 Click on this section to link to the DirectFET Website.
 Surface mounted on 1 in. square Cu board, steady state.
 T
C
measured with thermocouple mounted to top (Drain) of part.
 Repetitive rating; pulse width limited by max. junction temperature.
 Starting T
J
= 25°C, L = 0.77mH, R
G
= 25Ω, I
AS
= 11A.
Notes:
Fig 2. Typical Total Gate Charge vs. Gate-to-Source Voltage
IRF6641TRPbF
l RoHS Compliant 
l Lead-Free (Qualified up to 260°C Reflow)
l Application Specific MOSFETs
l Ideal for High Performance Isolated Converter
Primary Switch Socket
l Optimized for Synchronous Rectification
l Low Conduction Losses
l High Cdv/dt Immunity
l Dual Sided Cooling Compatible 
l Compatible with existing Surface Mount Techniques 
4 6 8 10 12 14 16
V
GS,
Gate -to -Source Voltage (V)
0
20
40
60
80
100
120
140
160
180
200
R
D
S
(
o
n
)
,
D
r
a
i
n
-
t
o
-
S
o
u
r
c
e
O
n
R
e
s
i
s
t
a
n
c
e
(
m
Ω
)
I
D
= 5.5A
T
J
= 25°C
T
J
= 125°C
0 5 10 15 20 25 30 35 40
Q
G
, Total Gate Charge (nC)
0.0
2.0
4.0
6.0
8.0
10.0
12.0
V
G
S
,
G
a
t
e
-
t
o
-
S
o
u
r
c
e
V
o
l
t
a
g
e
(
V
)
V
DS
= 160V
V
DS
= 100V
V
DS
= 40V
I
D
= 5.5A
SH SJ SP
MZ
MN
V
DSS
V
GS
R
DS(on)
200V max ±20V max
51mΩ@ 10V
Q
g tot
Q
gd
V
gs(th)
34nC 9.5nC 4.0V
Absolute Maximum Ratin
g
s
Parameter Units
V
DS
Drain-to-Source Voltage V
V
GS
Gate-to-Source Voltage
I
D
@ T
A
= 25°C
Continuous Drain Current, V
GS
@ 10V
I
D
@ T
A
= 70°C
Continuous Drain Current, V
GS
@ 10V
A
I
D
@ T
C
= 25°C
Continuous Drain Current, V
GS
@ 10V
I
DM
Pulsed Drain Current
E
AS
Single Pulse Avalanche Energy mJ
I
AR
Avalanche Current A
46
Max.
3.7
26
37
±20
200
4.6
11