For more information, please refer to the following application notes related to the power losses :

•

AN604: Calculation of conduction losses in a power rectifier

•

AN4021: Calculation of reverse losses on a power diode

1.1

Characteristics (curves)

Figure 1. Average forward power dissipation versus

average forward current

P

(W)

F(AV)

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

0.0

0.2

0.4

0.6

0.8

1.0

1.2

I

(A)

F(AV)

T

δ =tp/T

tp

δ =1

δ =0.5

δ =0.05

δ =0.1

δ =0.2

Figure 2. Average forward current versus ambient

temperature (δ = 0.5)

0.0

0.2

0.4

0.6

0.8

1.0

1.2

0

25

50

75

100

125

150

175

I

(A)

F(AV)

Rth(j-a) = Rth(j-l)

Rth(j-a) = 120 °C/W

T

=tp/T

tp

δ

T

(°C)

amb

SMA / DO-41

Figure 3. Normalized avalanche power derating versus

pulse duration (Tj = 125 °C)

P

(tp)

P

(10 µs)

ARM

ARM

0.001

0.01

0.1

1

1

10

100

1000

t (µs)

p

Figure 4. Relative variation of thermal impedance junction

to ambient versus pulse duration (SMA)

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

1.E-02

1.E-01

1.E+00

1.E+01

1.E+02

1.E+03

SMA

Z

/R

th(j-a)

th(j-a)

Single pulse

t ( s)

p

STPS1150

Characteristics (curves)

DS3281 - Rev 8

page 3/13