3
Motorola Bipolar Power Transistor Device Data
t, TIME (ms)
1.0
0.01
0.01
0.1
r(t), EFFECTIVE TRANSIENT THERMAL
1.0 1.0 100
R
θ
JC(t) = r(t) R
θ
JC
R
θ
JC(t) = 0.86
°
C/W MAX
D CURVES APPLY FOR POWER
PULSE TRAIN SHOWN
READ TIME AT t1
TJ(pk) – TC = P(pk) R
θ
JC(t)
P(pk)
t1t2
SINGLE PULSE
RESISTANCE (NORMALIZED)
1000
D = 0.5
0.2
0.05
DUTY CYCLE, D = t1/t2
Figure 3. Thermal Response
0.05
0.03
0.02
0.07
0.5
0.3
0.2
0.7
0.02 0.03 0.05 0.2 0.3 0.5 2.0 3.0 5.0 200 300 50010 20 30 50
0.1
0.02
0.01
VCE, COLLECTOR–EMITTER VOLTAGE (VOLTS)
5.0 10 20 2003.0 50 100
Figure 4. Maximum Rated Forward Bias Safe
Operating Area (FBSOA)
0.3
0.2
0
0.5
7.0 30 70 150
dc
0.1 ms
3.0
2.0
1.0
5.0
30
20
10
IC, COLLECTOR CURRENT (AMPS)
TJ = 175
°
C
SECOND BREAKDOWN LIMIT
BONDING WIRE LIMIT
THERMAL LIMITATION @ TC = 25
°
C
SINGLE PULSE
0.5 ms
1.0 ms
5.0 ms
MJ11017, 18
MJ11021, 22
FORWARD BIAS
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 4 is based on TJ(pk) = 175
_
C, TC is
variable dependIng on conditions. Second breakdown pulse
limits are valid for duty cycles to 10% provided TJ(pk)
v
175
_
C. TJ(pk) may be calculated from the data in Figure 3.
At high case temperatures thermal limitations will reduce the
power that can be handled to values less than the limitations
imposed by second breakdown.
20 100 140 2600 180 22060
VCE, COLLECTOR–EMITTER VOLTAGE (VOLTS)
20
0
Figure 5. Maximum RBSOA, Reverse Bias Safe
Operating Area
10
30
IC, COLLECTOR CURRENT (AMPS)
L = 200
µ
H
IC/IB1
≥
50
TC = 25
°
C
VBE(off) 0 – 5.0 V
RBE = 47
Ω
DUTY CYLE = 10%
MJ11017, 18
MJ11021, 22
REVERSE BIAS
For inductive loads, high voltage and high current must be
sustained simultaneously during turn–off, in most cases, with
the base to emitter junction reverse biased. Under these
conditions the collector voltage must be hold to a safe level
at or below a specific value of collector current. This can be
accomplished by several means such as active clamping,
RC snubbing, load line shaping, etc. The safe level for these
devices is specified as Reverse Bias Safe Operating Area
and represents the voltage–current conditions during re-
verse biased turn–off. This rating is verified under clamped
conditions so that the device is never subjected to an ava-
lanche mode. Figure 5 gives ROSOA characteristics.