BC450,A

3

Motorola Small–Signal Transistors, FETs and Diodes Device Data

Figure 2. Current–Gain — Bandwidth Product

IC, COLLECTOR CURRENT (mA)

–100

–70

–50

–30

–20

–10

–7.0

–5.0

–3.0

–2.0

–1.0

300

200

100

70

50

30

TJ = 25°C

VCE = –1.0 V

–5.0 V

Figure 3. Capacitance

VR, REVERSE VOLTAGE (VOLTS)

–100

–50

–20

–10

–5.0

–2.0

–1.0

–0.5

–0.2

–0.1

40

20

10

8.0

6.0

2.0

TJ = 25°C

Cobo

Cibo

4.0

Figure 4. Switching Times

IC, COLLECTOR CURRENT (mA)

–200

–100

–70

–50

–30

–20

–10

1000

VCC = –40 V

IC/IB = 10

IB1 = IB2

TJ = 25°C

700

500

300

200

100

70

50

30

20

10

ts

tf

tr

td @ VBE(off) = –0.5 V

Figure 5. Thermal Response

t, TIME (ms)

1.0

0.01

0.02

0.03

0.05

0.07

0.1

0.2

0.3

0.5

0.7

1.0

2.0

5.0

10

20

50

100

200

500

1.0 k

2.0 k

5.0 k

10 k

20 k

50 k

100 k

D = 0.5

0.2

0.1

0.02

0.01

SINGLE PULSE

DUTY CYCLE, D = t1/t2

D CURVES APPLY FOR POWER

PULSE TRAIN SHOWN

READ TIME AT t1 (SEE AN–469)

TJ(pk) – TC = P(pk) Z

θJC(t)

TJ(pk) – TA = P(pk) Z

θJA(t)

t1

t2

P(pk)

Z

θJC(t) = r(t) • RθJC

Z

θJA(t) = r(t) • RθJA

SINGLE PULSE