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BU323A Datasheet, PDF (4/6 Pages) Motorola, Inc – 16 AMPERE PEAK POWER TRANSISTOR DARLINGTON NPN SILICON 400 VOLTS 175 WATTS
BU323A
1
0.7 D = 0.5
0.5
0.3
0.2
0.2
0.1
0.1
0.05
0.07
0.05
0.02
0.03
0.01
0.02 SINGLE PULSE
0.01
0.01 0.02
0.05 0.1 0.2
RθJC(t) = r(t) RθJC
RθJC = °C/W MAX
D CURVES APPLY FOR POWER
PULSE TRAIN SHOWN
READ TIME AT t1
TJ(pk) – TC = P(pk) RθJC(t)
P(pk)
t1
t2
DUTY CYCLE, D = t1/t2
0.5
1
2
5
10 20
t, TIME (ms)
50 100 200
500 1000 2000
Figure 9. Thermal Response
50
20
100 µs
10
5
5.0 ms
2
1.0 ms
1
0.2
0.1
0.01
0.005
5
dc
TC = 25°C
BONDING WIRE LIMIT
THERMAL LIMIT (SINGLE PULSE)
SECOND BREAKDOWN LIMIT
10
20 30 50 70 100 200 300 500
VCE, COLLECTOR–EMITTER VOLTAGE (VOLTS)
Figure 10. Forward Bias Safe Operating Area
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 10 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 der-
ate the same as thermal limitations. Allowable current at the
voltages shown on Figure 10 may be found at any case tem-
perature by using the appropriate curve on Figure 11.
TJ(pk) may be calculated from the data in Figure 11. At high
case temperatures, thermal limitations will reduce the power
that can be handled to values less than the limitations im-
posed by second breakdown.
100
80
60
40
20
0
0
SECOND BREAKDOWN
DERATING
THERMAL
DERATING
VCC = 16 Vdc
t1
0 Vdc
50 ms
470
47
1N4001
BC337
VZ = 400 V (BU323A)
at IZ = 20 mA
INDUCTIVE LOAD
<1
11 mH
VZ
B
≈ 1K
100
1N4001
C
TUT
≈ 30
E
2.2
0.22
µF
40
80
120
160
TC, CASE TEMPERATURE (°C)
Figure 11. Power Derating
200
t1 to be selected such that IC reaches 10 Adc before switch–off.
NOTE: Figure 12 specifies energy handling capabilities in an automotive ignition circuit.
Figure 12. Ignition Test Circuit
3–234
Motorola Bipolar Power Transistor Device Data