2N5087

http://onsemi.com

6

Figure 17. Thermal Response

t, TIME (ms)

1.0

0.01

0.01

0.02

0.03

0.05

0.07

0.1

0.2

0.3

0.5

0.7

0.02

0.05 0.1 0.2

0.5

1.0 2.0

5.0

10

20

50

100 200

500 1.0k 2.0k

5.0k 10k 20k 50k 100k

D = 0.5

0.2

0.1

0.05

0.02

0.01

SINGLE PULSE

D CURVES APPLY FOR POWER

PULSE TRAIN SHOWN

t1

t2

P(pk)

FIGURE 19

Figure 18. Active–Region Safe Operating Area

TJ, JUNCTION TEMPERATURE (°C)

104

-40

Figure 19. Typical Collector Leakage Current

VCE, COLLECTOR-EMITTER VOLTAGE (VOLTS)

400

2.0

DESIGN NOTE: USE OF THERMAL RESPONSE DATA

A train of periodical power pulses can be represented by

the model as shown in Figure 19. Using the model and the

device thermal response the normalized effective transient

thermal resistance of Figure 17 was calculated for various

duty cycles.

To find Z

θJA(t), multiply the value obtained from Figure

17 by the steady state value R

θJA.

Example:

The 2N5087 is dissipating 2.0 watts peak under the follow-

ing conditions:

t1 = 1.0 ms, t2 = 5.0 ms (D = 0.2)

Using Figure 17 at a pulse width of 1.0 ms and D = 0.2, the

reading of r(t) is 0.22.

The peak rise in junction temperature is therefore

∆T = r(t) x P(pk) x RθJA = 0.22 x 2.0 x 200 = 88°C.

For more information, see ON Semiconductor Application

Note AN569/D, available from the Literature Distribution

Center or on our website at www.onsemi.com.

The safe operating area curves indicate IC–VCE limits of

the transistor that must be observed for reliable operation.

Collector load lines for specific circuits must fall below the

limits indicated by the applicable curve.

The data of Figure 18 is based upon TJ(pk) = 150°C; TC or

TA is variable depending upon conditions. Pulse curves are

valid for duty cycles to 10% provided TJ(pk) ≤ 150°C. TJ(pk)

may be calculated from the data in Figure 17. At high case

or ambient temperatures, thermal limitations will reduce the

power than can be handled to values less than the limitations

imposed by second breakdown.

10-2

10-1

100

101

102

103

-20

0

+20 +40 +60 +80 +100 +120 +140 +160

VCC = 30 V

ICEO

ICBO

AND

ICEX @ VBE(off) = 3.0 V

TA = 25°C

CURRENT LIMIT

THERMAL LIMIT

SECOND BREAKDOWN LIMIT

1.0 ms

10 µs

TC = 25°C

1.0 s

dc

dc

4.0

6.0

10

20

40

60

100

200

4.0

6.0 8.0 10

20

40

TJ = 150°C

100 µs