Datasheet

BDX33B BDX33C BDX34B BDX34C
http://onsemi.com
4
Figure 1. Thermal Response
t, TIME OR PULSE WIDTH (ms)
1.0
0.01
0.01
0.7
0.5
0.3
0.2
0.1
0.07
0.05
0.03
0.02
0.02
r(t) EFFECTIVE TRANSIENT
THERMAL RESISTANCE (NORMALIZED)
0.05 0.1 0.2 0.5 1.0 2.0 5.0 10 20 50 100 200 1000500
R
θ
JC
(t) = r(t) R
θ
JC
R
θ
JC
= 1.92°C/W
D CURVES APPLY FOR POWER
PULSE TRAIN SHOWN
READ TIME AT t
1
T
J(pk)
- T
C
= P
(pk)
R
θ
JC
(t)
P
(pk)
t
1
t
2
DUTY CYCLE, D = t
1
/t
2
D = 0.5
SINGLE PULSE
0.2
0.05
0.1
0.02
0.01
SINGLE
PULSE
0.03 0.3 3.0 30 300
20
1.0
10
5.0
2.0
1.0
0.5
0.02
3.0 5.0 7.0 10 20 30 50 10070
0.2
dc
5.0 ms
1.0 ms
BDX33B
BDX33C
500 µs
100
µs
T
C
= 25°C
CURVES APPLY BELOW RATED V
CEO
0.05
0.1
2.0
20
1.0
Figure 2. Active–Region Safe Operating Area
V
CE
, COLLECTOR-EMITTER VOLTAGE (VOLTS)
10
5.0
2.0
1.0
0.5
0.02
3.0 5.0 7.0 10 20 30 50 10070
0.2
I
C
, COLLECTOR CURRENT (AMP)
dc
5.0 ms
1.0 ms
BDX34B
BDX34C
500 µs
100
µs
T
C
= 25°C
BONDING WIRE LIMITED
THERMALLY LIMITED @ T
C
= 25°C
(SINGLE PULSE)
SECOND BREAKDOWN LIMITED
CURVES APPLY BELOW RATED V
CEO
0.05
0.1
2.0
V
CE
, COLLECTOR-EMITTER VOLTAGE (VOLTS)
I
C
, COLLECTOR CURRENT (AMP)
BONDING WIRE LIMITED
THERMALLY LIMITED @ T
C
= 25°C
(SINGLE PULSE)
SECOND BREAKDOWN LIMITED
There are two limitations on the power handling ability of
a transistor: average junction temperature and second
breakdown. Safe operating area curves indicate I
C
– V
CE
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 Fig. 3 is
based on T
J(pk)
= 150C; T
C
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 Fig. . At high case temperatures,
thermal limitations will reduce the power that can be
handled to values less than the limitations imposed by
second breakdown.