MJE5740 MJE5741 MJE5742

4

Motorola Bipolar Power Transistor Device Data

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 6 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 6 may be found at any case tem-

perature by using the appropriate curve on Figure 1.

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 Reverse Bias Safe Operating Area

and represents the voltage–current condition allowable dur-

ing reverse biased turnoff. This rating is verified under

clamped conditions so that the device is never subjected to

an avalanche mode. Figure 7 gives the complete RBSOA

characteristics.

The Safe Operating Area figures shown in Figures 6 and 7 are specified ratings for these devices under the test conditions shown.

VCE, COLLECTOR–EMITTER VOLTAGE (VOLTS)

VCE, COLLECTOR–EMITTER VOLTAGE (VOLTS)

Figure 6. Forward Bias Safe Operating Area

Figure 7. Reverse Bias Safe Operating Area

16

14

12

8

0

2

4

10

100

200

300

500

0

400

16

5

10

8

1

0.02

100

0.1

10

20

200

400

3

0.5

50

0.3

0.05

dc

1 ms

100

µs

MJE5742

MJE5741

MJE5740

VBE(off) ≤ 5 V

TJ = 100°C

6

CURVES APPLY BELOW RATED VCEO

10

µs

MJE5742

MJE5741

MJE5740

5 ms

BONDING WIRE LIMIT

THERMAL LIMIT

(SINGLE PULSE)

SECOND BREAKDOWN LIMIT

IC, COLLECTOR CURRENT (AMPS)

0.5 0.7

1

2

10

7

5

2

1

0.7

0.2

0.3

5

0.5

10

3

3

0.3

0.2

7

IC, COLLECTOR CURRENT (AMPS)

0.5 0.7

1

2

10

0.7

0.5

0.2

0.1

0.07

0.02

0.3

Figure 8. Turn–On Time

5

0.05

1

Figure 9. Turn–Off Time

3

VCC = 250 V

IB1 = IB2

IC/IB = 20

ts

tr

tf

td

VCC = 250 V

IB1 = IB2

IC/IB = 20

0.3

0.03

0.2

7

RESISTIVE SWITCHING PERFORMANCE