1.0
0.7
0.5
D = 0.5
0.3
0.2
0.2
0.1
P
(pk)
θ
θ
(t) = r(t) θ
JC
JC
JC
= 1.67°C/W
0.1
0.07
0.05
0.05
0.02
D CURVES APPLY FOR POWER
PULSE TRAIN SHOWN
READ TIME AT t
t
1
1
t
2
T
– T = P (t)
C
θ
J(pk)
(pk) JC
0.03
0.02
0.01
DUTY CYCLE, D = t /t
1 2
SINGLE PULSE
0.01
0.01
0.02 0.03 0.05
0.1
0.2 0.3 0.5
1.0
2.0 3.0 5.0
10
20 30
50
100
200 300 500
1000
t, TIME OR PULSE WIDTH (ms)
Figure 4. Thermal Response
20
10
100 µs
There are two limitations on the power handling ability of a
transistor: average junction temperature and second break-
5.0
down. Safe operating area curves indicate I – V
limits of
500 µs
1.0 ms
5.0 ms
C
CE
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.
2.0
1.0
0.5
dc
T = 150°C
J
BONDING WIRE LIMITED
THERMALLY LIMITED @ T = 25°C
(SINGLE PULSE)
SECOND BREAKDOWN LIMITED
The data of Figure 5 is based on T
J(pk)
= 150 C; T is
C
C
variable depending on conditions. Second breakdown pulse
limits are valid for duty cycles to 10% provided T
0.2
0.1
J(pk)
may be calculated from the data in Figure 4.
CURVES APPLY BELOW RATED V
CEO
< 150 C. T
J(pk)
2N6040, 2N6043
2N6041, 2N6044
2N6045
At high case temperatures, thermal limitations will reduce the
power that can be handled to values less than the limitations
imposed by second breakdown.
0.05
0.02
1.0
2.0 3.0
5.0 7.0 10
20 30
50 70 100
V , COLLECTOR–EMITTER VOLTAGE (VOLTS)
CE
Figure 5. Active–Region Safe Operating Area
300
10,000
5000
T = 25°C
J
3000
2000
200
1000
C
ob
500
T
= 25°C
= 4.0 Vdc
= 3.0 Adc
C
100
70
300
200
V
CE
C
I
C
ib
100
50
30
20
50
PNP
NPN
PNP
NPN
30
10
0.1
0.2
0.5 1.0 2.0
5.0 10
20
50 100
1.0
2.0
5.0 10
20
50 100 200
500 1000
V , REVERSE VOLTAGE (VOLTS)
R
f, FREQUENCY (kHz)
Figure 7. Capacitance
Figure 6. Small–Signal Current Gain
3–91
Motorola Bipolar Power Transistor Device Data