MJ10009

6

Motorola Bipolar Power Transistor Device Data

The Safe Operating Area figures shown in Figures 11 and 12 are

specified ratings for these devices under the test conditions

shown.

50

Figure 11. Forward Bias Safe Operating Area

VCE, COLLECTOR–EMITTER VOLTAGE (VOLTS)

20

5

1

0.5

0.1

0.005

6

10

20

600

BONDING WIRE LIMIT

THERMAL LIMIT @ TC = 25°C

(SINGLE PULSE)

SECOND BREAKDOWN LIMIT

50

0.05

dc

0.2

100

200

450

100

µs

10

µs

20

0

Figure 12. Reverse Bias Switching

Safe Operating Area (MJ10009)

VCE, COLLECTOR–EMITTER VOLTAGE (VOLTS)

16

12

0

500

4

8

300

400

100

200

VBE(off) = 5 V

1 ms

MJ10009

VBE(off) = 2 V

VBE(off) = 0 V

TC = 100°C

IC/IB1 ≥ 20

10

2

0.02

0.01

500

18

14

10

6

2

SAFE OPERATING AREA INFORMATION

FORWARD BIAS

There are two limitations on the power handling ability of a

transistor: average junction temperature and second break-

down. Safe operating area curves indicate IC – VCE limits of

the transistor that must be observed for reliable operation,

i.e., the transistor must not be subjected to greater dissipa-

tion than the curves indicate.

The data of Figure 11 is based on TC = 25_C; TJ(pk) is

variable depending on power level. Second breakdown pulse

limits are valid for duty cycles to 10% but must be derated

when TC ≥ 25_C. Second breakdown limitations do not der-

ate the same as thermal limitations. Allowable current at the

voltages shown on Figure 11 may be found at any case tem-

perature by using the appropriate curve on Figure 13.

TJ(pk) may be calculated from the data in Figure 10. At

high case temperatures, thermal limitations will reduce the

power that can be handled to values less than the limitations

imposed by second breakdown.

REVERSE BIAS

For inductive loads, high voltage and high current must be

sustained simultaneously during turn–off, in most cases, with

the base to emitter junction reverse biased. Under these

conditions the collector voltage must be held to a safe level

at or below a specific value of collector current. This can be

accomplished by several means such as active clamping,

RC snubbing, load line shaping, etc. The safe level for these

devices is specified as VCEX(sus) at a given collector current

and represents a voltage–current condition that can be sus-

tained during reverse biased turn–off. This rating is verified

under clamped conditions so that the device is never sub-

jected to an avalanche mode. Figure 12 gives the complete

reverse bias safe operating area characteristics. See Table 1

for circuit conditions.

10

0

Figure 13. Power Derating

VBE(off), REVERSE BASE CURRENT (VOLTS)

7

5

0

2

5

8

7

2

IC = 10 A

1

SEE TABLE 1 FOR CONDITIONS,

FIGURE 7 FOR WAVESHAPE.

100

80

60

20

0

0

40

80

120

200

Figure 14. Reverse Base Current versus

VBE(off) with No External Base Resistance

TC, CASE TEMPERATURE (°C)

THERMAL DERATING

FORWARD BIAS

SECOND BREAKDOWN

DERATING

160

40