BCW69LT1 Motorola Inc, BCW69LT1 Datasheet - Page 6

• Manufacturer Part Number: BCW69LT1
• Description: General Purpose Transistors
• Manufacturer: Motorola Inc

BCW69LT1 BCW70LT1
6
10 –1
10 –2
10 4
10 3
10 2
10 1
10 0
– 4
0
Figure 15. Typical Collector Leakage Current
V CC = 30 V
– 2
0
0
T J , JUNCTION TEMPERATURE ( C)
+ 20 + 40 + 60 + 80 + 100 + 120 + 140 + 160
I CEO
I CEX @ V BE(off) = 3.0 V
I CBO
AND
Motorola Small–Signal Transistors, FETs and Diodes Device Data
as shown in Figure 16. Using the model and the device thermal
response the normalized effective transient thermal resistance of
Figure 14 was calculated for various duty cycles.
steady state value R JA .
Example:
Dissipating 2.0 watts peak under the following conditions:
Using Figure 14 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
For more information, see AN–569.
DESIGN NOTE: USE OF THERMAL RESPONSE DATA
A train of periodical power pulses can be represented by the model
To find Z JA(t) , multiply the value obtained from Figure 14 by the
T = r(t) x P (pk) x R JA = 0.22 x 2.0 x 200 = 88 C.
t 1 = 1.0 ms, t 2 = 5.0 ms (D = 0.2)