irf2805 International Rectifier Corp., irf2805 Datasheet - Page 7

• Manufacturer Part Number: irf2805
• Description: 55v Single N-channel Hexfet Power Mosfet In A To-220ab Package
• Manufacturer: International Rectifier Corp.

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10000
1000
100
500
400
300
200
100
10
1.0E-07
1
0
Fig 16. Maximum Avalanche Energy
25
Duty Cycle = Single Pulse
Starting T J , Junction Temperature (°C)
50
Vs. Temperature
0.01
0.05
0.10
1.0E-06
75
T OP
BOTT OM 10% Duty Cycle
I D = 104A
Fig 15. Typical Avalanche Current Vs.Pulsewidth
100
Single Pulse
125
1.0E-05
150
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
1.0E-04
Purely a thermal phenomenon and failure occurs at a
not exceeded.
Figures 12a, 12b.
T
t
D = Duty cycle in avalanche = t
Z
temperature far in excess of T
every part type.
avalanche pulse.
voltage increase during avalanche).
av
av =
thJC
D (ave)
jmax
= Allowable avalanche current.
=
Average time in avalanche.
(D, t
Allowable rise in junction temperature, not to exceed
(assumed as 25°C in Figure 15, 16).
= Average power dissipation per single
av
P
) = Transient thermal resistance, see figure 11)
D (ave)
1.0E-03
= 1/2 ( 1.3·BV·I
I
E
Allowed avalanche Current vs
avalanche pulsewidth, tav
assuming
avalanche losses. Note: In no
case should Tj be allowed to
exceed Tjmax
av
AS (AR)
= 2DT/ [1.3·BV·Z
= P
D (ave)
jmax
Tj = 25°C due to
av
av
. This is validated for
·f
) = DT/ Z
1.0E-02
·t
th
av
]
thJC
jmax
1.0E-01
7
is