BDW42 BDW46 BDW47

3–214

Motorola Bipolar Power Transistor Device Data

Figure 4. Thermal Response

t, TIME OR PULSE WIDTH (ms)

1.0

0.01

0.01

0.7

0.5

0.3

0.2

0.1

0.07

0.05

0.03

0.02

0.02

0.05

0.1

0.2

0.5

1.0

2.0

5.0

10

20

50

100

200

1000

500

R

θJC(t) = r(t) RθJC

R

θJC = 1.92°C/W

D CURVES APPLY FOR POWER

PULSE TRAIN SHOWN

READ TIME AT t1

TJ(pk) – TC = P(pk) R

θJC(t)

P(pk)

t1

t2

DUTY CYCLE, D = t1/t2

D = 0.5

SINGLE PULSE

0.2

0.05

0.1

0.02

0.01

0.03

0.3

3.0

30

300

ACTIVE–REGION SAFE OPERATING AREA

SECOND BREAKDOWN LIMIT

BONDING WIRE LIMIT

THERMAL LIMITED

@ TC = 25°C (SINGLE PULSE)

50

1.0

Figure 5. BDW42

20

2.0

0.05

10

20

100

TJ = 25°C

BDW42

1.0 ms

0.1 ms

0.2

5.0

0.5

VCE, COLLECTOR–EMITTER VOLTAGE (VOLTS)

10

30

70

1.0

0.1

0.5 ms

dc

2.0

50

3.0

5.0

7.0

Figure 6. BDW46 and BDW47

SECOND BREAKDOWN LIMIT

BONDING WIRE LIMIT

THERMAL LIMITED

@ TC = 25°C (SINGLE PULSE)

50

1.0

20

2.0

0.05

10

20

100

TJ = 25°C

BDW46

BDW47

1.0 ms

0.1 ms

0.2

5.0

0.5

VCE, COLLECTOR–EMITTER VOLTAGE (VOLTS)

10

30

70

1.0

0.1

0.5 ms

dc

2.0

50

3.0

5.0

7.0

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 dissipation than the

curves indicate. The data of Fig. 5 and 6 is based on TJ(pk) =

200

_C; TC is variable depending on conditions. Second break-

down pulse limits are valid for duty cycles to 10% provided

TJ(pk) v 200_C. TJ(pk) may be calculated from the data in

Fig. 4. At high case temperatures, thermal limitations will re-

duce the power that can be handled to values less than the li-

mitations imposed by second breakdown.

* Linear extrapolation

10,000

1.0

Figure 7. Small–Signal Current Gain

f, FREQUENCY (kHz)

10

2.0

5.0

10

20

50

100

200

1000

500

300

100

5000

20

3000

200

500

2000

1000

30

50

BDW46, 47 (PNP)

BDW42 (NPN)

TJ = 25°C

VCE = 3.0 V

IC = 3.0 A

300

0.1

Figure 8. Capacitance

VR, REVERSE VOLTAGE (VOLTS)

30

1.0

2.0

5.0

20

100

10

200

100

70

50

TJ = + 25°C

Cib

Cob

50

0.2

0.5

BDW46, 47 (PNP)

BDW42 (NPN)