r(t), TRANSIENT THERMAL RESISTANCE (NORMALIZED)
TIP41A TIP41B TIP41C TIP42A TIP42B TIP42C
1.0
0.7
0.5
0.3
0.2
0.1
0.07
0.05
0.03
0.02
0.01
0.01
0.01
SINGLE PULSE
0.02
0.05
1.0
0.2
0.5
1.0
D = 0.5
0.2
0.1
0.05
0.02
Z
θJC(t)
= r(t) R
θJC
R
θJC
= 1.92°C/W MAX
D CURVES APPLY FOR POWER
PULSE TRAIN SHOWN
READ TIME AT t1
TJ(pk) – TC = P(pk) Z
θJC(t)
2.0
5.0
t, TIME (ms)
10
20
50
P(pk)
t1
t2
DUTY CYCLE, D = t1/t2
100
200
500
1.0 k
Figure 4. Thermal Response
10
0.5 ms
IC, COLLECTOR CURRENT (AMP)
5.0
3.0
2.0
1.0
0.5
0.3
0.2
1.0 ms
TJ = 150°C
SECONDARY BREAKDOWN LTD
BONDING WIRE LTD
THERMAL LIMITATION @ TC = 25°C
(SINGLE PULSE)
CURVES APPLY BELOW RATED VCEO
5.0 ms
TIP41A, TIP42A
TIP41B, TIP42B
TIP41C, TIP42C
40
10
20
60
VCE, COLLECTOR–EMITTER VOLTAGE (VOLTS)
80 100
0.1
5.0
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 T J(pk) = 150
_
C; TC is
variable depending on conditions. Second breakdown pulse
limits are valid for duty cycles to 10% provided T J(pk)
150
_
C. T J(pk) may be calculated from the data in
Figure 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.
v
Figure 5. Active–Region Safe Operating Area
5.0
3.0
2.0
1.0
t, TIME (
µ
s)
0.7
0.5
0.3
0.2
0.1
0.07
0.05
0.06
tf
ts
TJ = 25°C
VCC = 30 V
IC/IB = 10
IB1 = IB2
300
TJ = 25°C
200
C, CAPACITANCE (pF)
Cib
100
70
50
Cob
0.1
0.2
0.4 0.6
1.0
2.0
IC, COLLECTOR CURRENT (AMP)
4.0
6.0
30
0.5
1.0
2.0 3.0
5.0
10
20
VR, REVERSE VOLTAGE (VOLTS)
30
50
Figure 6. Turn–Off Time
Figure 7. Capacitance
Motorola Bipolar Power Transistor Device Data
3
ONSEMI [ ON SEMICONDUCTOR ]
