BD243B BD243C BD244B BD244C

3

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(max) = 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

SECOND BREAKDOWN LIMITED

BONDING WIRE LIMITED

THERMAL LIMITATION @ TC = 25°C

CURVES APPLY BELOW RATED VCEO

10

5.0

Figure 5. Active Region Safe Operating Area

5.0

1.0

0.1

10

20

60

100

TJ = 150°C

BD243B, BD244B

BD243C, BD244C

5.0 ms

0.5 ms

0.2

2.0

0.5

VCE, COLLECTOR–EMITTER VOLTAGE (VOLTS)

3.0

0.3

40

80

1.0

ms

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 5 is based on TJ(pk) = 150_C: TC is

variable depending on conditions. Second breakdown pulse

limits are valid for duty cycles to 10% provided TJ(pk)

v 150_C, TJ(pk) may be calculated from the data in Fig-

ure 4. At high case temperatures, thermal limitations will

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

limitations imposed by second breakdown.

5.0

0.06

Figure 6. Turn-Off Time

IC, COLLECTOR CURRENT (AMP)

2.0

1.0

0.5

0.3

0.2

0.1

0.07

0.05

0.1

0.2

0.4

0.6

2.0

6.0

TJ = 25°C

VCC = 30 V

IC/IB = 10

IB1 = IB2

ts

1.0

4.0

0.7

3.0

tf

300

0.5

Figure 7. Capacitance

VR, REVERSE VOLTAGE (VOLTS)

30

1.0

2.0

3.0

5.0

20

30

50

10

200

100

70

50

TJ = 25°C

Cib

Cob