IRF7748L1PBF Datasheet, PDF (6/10 Pages) International Rectifier – DirectFET™ Power MOSFET

IRF7748L1TRPbF
1000
100
10
Duty Cycle = Single Pulse
0.01
0.05
0.10
Allowed avalanche Current vs avalanche
pulsewidth, tav, assuming Tj = 150°C and
Tstart =25°C (Single Pulse)
1
Allowed avalanche Current vs avalanche
pulsewidth, tav, assuming  j = 25°C and
Tstart = 150°C.
0.1
1.0E-06
1.0E-05
1.0E-04
tav (sec)
1.0E-03
1.0E-02
Fig 15. Typical Avalanche Current vs. Pulse width
1.0E-01
140
TOP
Single Pulse
120
BOTTOM 1.0% Duty Cycle
ID = 89A
100
80
60
40
20
0
25 50 75 100 125 150 175
Starting TJ , Junction Temperature (°C)
Fig 16. Maximum Avalanche Energy vs. Temperature
Notes on Repetitive Avalanche Curves , Figures 15, 16:
(For further info, see AN-1005 )
1.Avalanche failures assumption:
Purely a thermal phenomenon and failure occurs at a
temperature far in excess of T_jmax. This is validated for every
part type.
2. Safe operation in Avalanche is allowed as long asT_jmax is not
exceeded.
3. Equation below based on circuit and waveforms shown in Figures
19a, 19b.
4. P_{D (ave)} = Average power dissipation per single avalanche pulse.
5. BV = Rated breakdown voltage (1.3 factor accounts for voltage
increase during avalanche).
6. I_av = Allowable avalanche current.
7. T = Allowable rise in junction temperature, not to exceed
T_jmax (assumed as 25°C in Figure 15, 16).
t_av = Average time in avalanche.
D = Duty cycle in avalanche = tav ·f
Z_thJC(D, t_av) = Transient thermal resistance, see Figures 3)
PD (ave) = 1/2 ( 1.3·BV·I_av) = T/ Z_thJC
I_av = 2T/ [1.3·BV·Z_th]
E_{AS (AR)} = P_{D (ave)·}t_av
Fig 17. Peak Diode Recovery dv/dt Test Circuit for N-Channel HEXFET^® Power MOSFETs
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February 18, 2013