BUV21

3

Motorola Bipolar Power Transistor Device Data

Figure 2. Active Region Safe Operating Area

40

1

VCE, COLLECTOR–EMITTER VOLTAGE (V)

10

200

10

1

0.1

100

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 2 is based on TC = 25_C, TJ(pk) is

variable depending on power level. Second breakdown

limitations do not derate the same as thermal limitations.

At high case temperatures, thermal limitations will reduce

the power that can be handled to values less than the limita-

tions imposed by second breakdown.

Figure 3. “On” Voltages

Figure 4. DC Current Gain

50

100

IC, COLLECTOR CURRENT (A)

1

10

40

0

30

20

10

VCE = 5 V

Figure 5. Resistive Switching Performance

3.0

0

5

10

15

25

VCE = 100 V

IC/IB1 = 8

IB1 = IB2

2.0

1.0

tS

0.4

0.3

0.2

20

ton

tF

2.0

IC, COLLECTOR CURRENT (A)

1

10

1.6

IC/IB = 8

0.8

1.2

0.4

Figure 6. Switching Times Test Circuit

IC, COLLECTOR CURRENT (A)

VBE

VCE

VCC

IB2

IB1

RB

RC

RC – RB: Non inductive resistances

VCC = 100 V

RC = 4 Ω

RB = 2.2 Ω

10,000

µF

0