irlr2908 International Rectifier Corp., irlr2908 Datasheet - Page 7

• Manufacturer Part Number: irlr2908
• Description: Hexfet Power Mosfet Automotive Mosfet
• Manufacturer: International Rectifier Corp.

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1000
100
0.1
200
150
100
10
50
1.0E-08
1
0
Fig 16. Maximum Avalanche Energy
25
Starting T J , Junction Temperature (°C)
Duty Cycle = Single Pulse
50
0.05
0.10
0.01
vs. Temperature
1.0E-07
TOP
BOTTOM 10% Duty Cycle
I D = 23A
75
100
Fig 15. Typical Avalanche Current vs.Pulsewidth
Single Pulse
1.0E-06
125
150
1.0E-05
175
tav (sec)
Notes on Repetitive Avalanche Curves , Figures 15, 16:
(For further info, see AN-1005 at www.irf.com)
1. Avalanche failures assumption:
2. Safe operation in Avalanche is allowed as long asT
3. Equation below based on circuit and waveforms shown in
4. P
5. BV = Rated breakdown voltage (1.3 factor accounts for
6. I
7. 'T
t
Purely a thermal phenomenon and failure occurs at a
temperature far in excess of T
every part type.
not exceeded.
Figures 12a, 12b.
avalanche pulse.
voltage increase during avalanche).
T
D = Duty cycle in avalanche = t
Z
av =
av
thJC
jmax
D (ave)
= Allowable avalanche current.
=
Average time in avalanche.
(D, t
Allowable rise in junction temperature, not to exceed
IRLR2908/IRLU2908
1.0E-04
(assumed as 25°C in Figure 15, 16).
= Average power dissipation per single
av
P
) = Transient thermal resistance, see figure 11)
D (ave)
= 1/2 ( 1.3·BV·I
I
Allowed avalanche Current vs
avalanche
assuming ' Tj = 25° C due to
avalanche losses
E
av
AS (AR)
= 2DT/ [1.3·BV·Z
1.0E-03
= P
D (ave)
jmax
pulsewidth,
av
av
. This is validated for
·f
) = DT/ Z
·t
th
av
1.0E-02
]
thJC
tav
jmax
1.0E-01
7
is