MJD18002D2

http://onsemi.com

9

10

ms

Figure 27. Forward Bias Safe Operating Area

100

10

0.01

Figure 28. Reverse Bias Safe Operating Area

2

0

1200

200

0

Figure 29. Forward Bias Power Derating

40

20

0

0.1

10

160

0.2

0.4

0.6

1

0.5

1

1

2.5

400

800

1000

0.8

60

100

80

120

140

1000

600

1.5

Otherwise Specified

Second Breakdown Derating

Thermal Derating

DC

50

ms

1

ms

5 ms

1 ms

Gain = 4

02

4

6

8

10

12

8

6

4

10

2

0

There are two limitations on the power handling ability of

a transistor: average junction temperature and second

limits of the transistor that must be observed for reliable

operation; i.e., the transistor must not be subjected to greater

dissipation than the curves indicate. The data of Figure 27 is

level. Second breakdown pulse limits are valid for duty

Breakdown limitations do not derate the same as thermal

limitations. Allowable current at the voltages shown on

Figure 27 may be found at any case temperature by using the

appropriate curve on Figure 29.

case temperatures, thermal limitations will reduce the power

that can be handled to values less than the limitations

imposed by second breakdown. For inductive loads, high

voltage and current must be sustained simultaneously during

turn−off with the base to emitter junction reverse biased. The

safe level is specified as a reverse biased safe operating area

(Figure 28). This rating is verified under clamped conditions

so that the device is never subjected to an avalanche mode.