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IRF644N/644NS/644NL

Fig 11. Maximum Effective Transient Thermal Impedance, Junction-to-Case

Fig 9. Maximum Drain Current Vs.

Case Temperature

90%

10%

Pulse Width

≤ 1 µs

Duty Factor

≤ 0.1 %

D.U.T.

+

Fig 10a. Switching Time Test Circuit

Fig 10b. Switching Time Waveforms

25

50

75

100

125

150

175

0

3

6

9

12

15

T , Case Temperature ( C)

°

C

0.01

0.1

1

10

0.00001

0.0001

0.001

0.01

0.1

1

Notes:

1. Duty factor D = t / t

2. Peak T = P

x Z

+ T

1

2

J

DM

thJC

C



P

t

t

DM

1

2

t , Rectangular Pulse Duration (sec)

1

0.01

0.02

0.05

0.10

0.20

D = 0.50

SINGLE PULSE

(THERMAL RESPONSE)