MJ10023
The Safe Operating Area figures shown in Figures 13 and 14
are specified for these devices under the test conditions
shown.
100
50
20
10
5.0
2.0
1.0
0.5
0.2
0.1
0.05
0.02
0.01
1.0
10 µs
(TURN-ON SWITCHING)
dc
TC = 25°C
BONDING WIRE LTD
THERMAL LTD
SECOND BREAKDOWN LTD
2.0 5.0 10 20 50 100 200 400
VCE, COLLECTOR-EMITTER VOLTAGE (VOLTS)
Figure 13. Maximum Forward Bias Safe
Operating Area
80
IC/IB ≥ 20
25°C ≤ TJ ≤ 100°C
70
60
TURN-OFF LOAD LINE
50
40
30
20
10
RBE = 24 Ω
2 V ≤ VBE(off) ≤ 8 V
0 0 100 200 300 400 500 600 700
VCEM, PEAK COLLECTOR-EMITTER VOLTAGE (VOLTS)
Figure 14. Maximum RBSOA, Reverse Bias
Safe Operating Area
100
80
SAFE OPERATING AREA INFORMATION
FORWARD BIAS
There are two limitations on the power handling ability of
a transistor: average junction temperature and second
breakdown. 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
dissipation than the curves indicate.
The data of Figure 13 is based on TC = 25_C; TJ(pk) is
variable depending on power level. Second breakdown
pulse limits are valid for duty cycles to 10% but must be
derated when TC ≥ 25°C. Second breakdown limitations do
not derate the same as thermal limitations. Allowable
current at the voltages shown on Figure 13 may be found at
any case temperature by using the appropriate curve on
Figure 15.
TJ(pk) may be calculated from the data in Figure 12. At
high case temperatures, thermal limitations will reduce the
power that can be handled to values less than the limitations
imposed by second breakdown.
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 held 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 condition allowable
during reverse biased turn–off. This rating is verified under
clamped conditions so that the device is never subjected to
an avalanche mode. Figure 14 gives the RBSOA
characteristics.
SECOND BREAKDOWN
DERATING
60
40
THERMAL
DERATING
20
0
0
40
80
120
160
200
TC, CASE TEMPERATURE (°C)
Figure 15. Power Derating
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