BU323Z
http://onsemi.com
4
Figure 1. I
C
= f(V
CE
) Curve Shape
I
C
I
NOM
= 6.5 A
Output transistor turns on: I
C
= 40 mA
High Voltage Circuit turns on: I
C
= 20 mA
Avalanche diode turns on: I
C
= 100 mA
Icer Leakage Current
250 V 300 V 340 V
V
CE
V
CLAMP
NOMINAL
= 400 V
By design, the BU323Z has a built−in avalanche diode and
a special high voltage driving circuit. During an
auto−protect cycle, the transistor is turned on again as soon
as a voltage, determined by the zener threshold and the
network, is reached. This prevents the transistor from going
into a Reverse Bias Operating limit condition. Therefore, the
device will have an extended safe operating area and will
always appear to be in “FBSOA.” Because of the built−in
zener and associated network, the I
C
= f(V
CE
) curve exhibits
an unfamiliar shape compared to standard products as
shown in Figure 1.
Figure 2. Basic Energy Test Circuit
MERCURY CONTACTS
WETTED RELAY
V
CE
MONITOR
(V
GATE
)
L INDUCTANCE
(8 mH)
I
B
CURRENT
SOURCE
V
BEoff
I
B2
SOURCE
I
C
CURRENT
SOURCE
0.1 W
NON
INDUCTIVE
I
C
MONITOR
R
BE
= 100 W
The bias parameters, V
CLAMP
, I
B1
, V
BE(off)
, I
B2
, I
C
, and
the inductance, are applied according to the Device Under
Test (DUT) specifications. V
CE
and I
C
are monitored by the
test system while making sure the load line remains within
the limits as described in Figure 4.
Note: All BU323Z ignition devices are 100% energy
tested, per the test circuit and criteria described in Figures 2
and 4, to the minimum guaranteed repetitive energy, as
specified in the device parameter section. The device can
sustain this energy on a repetitive basis without degrading
any of the specified electrical characteristics of the devices.
The units under test are kept functional during the complete
test sequence for the test conditions described:
I
C(peak)
= 7.0 A, I
C
H = 5.0 A, I
C
L = 100 mA, I
B
= 100 mA,
R
BE
= 100 W, V
gate
= 280 V, L = 8.0 mH
Figure 3. Forward Bias Safe Operating Area
V
CE
, COLLECTOR-EMITTER VOLTAGE (VOLTS)
1000340V10010
0.001
0.01
0.1
1
10
T
C
= 25°C
250ms
10ms
1ms
300ms
I
C
, COLLECTOR CURRENT (AMPS)
THERMAL LIMIT
SECOND BREAKDOWN LIMIT
CURVES APPLY BELOW
RATED V
CEO
