BDX33B BDX33C BDX34B BDX34C

3

Motorola Bipolar Power Transistor Device Data

Figure 1. 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

SINGLE

PULSE

0.03

0.3

3.0

30

300

20

1.0

10

5.0

2.0

1.0

0.5

0.02

3.0

5.0

7.0

10

20

30

50

100

70

0.2

dc

5.0 ms

1.0 ms

BDX33B

BDX33C

500

µs

100

µs

TC = 25°C

CURVES APPLY BELOW RATED VCEO

0.05

0.1

2.0

20

1.0

Figure 2. Active–Region Safe Operating Area

VCE, COLLECTOR–EMITTER VOLTAGE (VOLTS)

10

5.0

2.0

1.0

0.5

0.02

3.0

5.0

7.0

10

20

30

50

100

70

0.2

dc

5.0 ms

1.0 ms

BDX34B

BDX34C

500

µs

100

µs

TC = 25°C

BONDING WIRE LIMITED

THERMALLY LIMITED @ TC = 25°C

(SINGLE PULSE)

SECOND BREAKDOWN LIMITED

CURVES APPLY BELOW RATED VCEO

0.05

0.1

2.0

VCE, COLLECTOR–EMITTER VOLTAGE (VOLTS)

BONDING WIRE LIMITED

THERMALLY LIMITED @ TC = 25°C

(SINGLE PULSE)

SECOND BREAKDOWN LIMITED

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 Fig. 3 is based on

TJ(pk) = 150_C; TC is variable depending on conditions. Se-

cond breakdown pulse limits are valid for duty cycles to 10%

provided TJ(pk) = 150_C. TJ(pk) may be calculated from the

data in Fig. . At high case temperatures, thermal limitations

will reduce the power that can be handled to values less than

the limitations imposed by second breakdown.

10,000

1.0

Figure 3. 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

300

0.1

Figure 4. 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

TJ = 25°C

VCE = 4.0 Vdc

IC = 3.0 Adc

PNP

NPN

PNP

NPN