Philips Semiconductors
Product specification
Silicon Diffused Power Transistor
BU4508AX
GENERAL DESCRIPTION
Enhanced performance, new generation, high-voltage, high-speed switching npn transistor in a plastic full-pack
envelope intended for use in horizontal deflection circuits of colour television receivers an p.c monitors. Features
exceptional tolerance to base drive and collector current load variations resulting in a very low worst case
dissipation.
QUICK REFERENCE DATA
SYMBOL
PARAMETER
CONDITIONS
TYP.
MAX.
UNIT
V
CESM
Collector-emitter voltage peak value
V
BE
= 0 V
-
1500
V
V
CEO
Collector-emitter voltage (open base)
-
800
V
I
C
Collector current (DC)
-
8
A
I
CM
Collector current peak value
-
15
A
P
tot
Total power dissipation
T
hs
25 C
-
45
W
V
CEsat
Collector-emitter saturation voltage
I
C
= 5.0 A; I
B
= 1.25 A
-
3.0
V
I
Csat
Collector saturation current
f = 16kHz
5.0
-
A
f = 64kHz
4.0
-
A
t
f
Fall time
I
Csat
= 5A; f = 16kHz
0.35
0.48
s
I
Csat
= 4A; f = 64kHz
0.17
-
s
PINNING - SOT399
PIN CONFIGURATION
SYMBOL
PIN
DESCRIPTION
1
base
2
collector
3
emitter
case isolated
LIMITING VALUES
Limiting values in accordance with the Absolute Maximum Rating System (IEC 134)
SYMBOL
PARAMETER
CONDITIONS
MIN.
MAX.
UNIT
V
CESM
Collector-emitter voltage peak value
V
BE
= 0 V
-
1500
V
V
CEO
Collector-emitter voltage (open base)
-
800
V
I
C
Collector current (DC)
-
8
A
I
CM
Collector current peak value
-
15
A
I
B
Base current (DC)
-
4
A
I
BM
Base current peak value
-
6
A
-I
BM
Reverse base current peak value
1
-
5
A
P
tot
Total power dissipation
T
hs
25 C
-
45
W
T
stg
Storage temperature
-55
150
C
T
j
Junction temperature
-
150
C
THERMAL RESISTANCES
SYMBOL
PARAMETER
CONDITIONS
TYP.
MAX.
UNIT
R
th j-hs
Junction to heatsink
with heatsink compound
-
2.8
K/W
R
th j-a
Junction to ambient
in free air
35
-
K/W
case
1 2 3
b
c
e
1 Turn-off current.
May 1998
1
Rev 1.000
Philips Semiconductors
Product specification
Silicon Diffused Power Transistor
BU4508AX
ISOLATION LIMITING VALUE & CHARACTERISTIC
T
hs
= 25 C unless otherwise specified
SYMBOL
PARAMETER
CONDITIONS
MIN.
TYP.
MAX.
UNIT
V
isol
Repetitive peak voltage from all
R.H.
65 % ; clean and dustfree
-
-
2500
V
three terminals to external
heatsink
C
isol
Capacitance from T2 to external f = 1 MHz
-
22
-
pF
heatsink
STATIC CHARACTERISTICS
T
hs
= 25 C unless otherwise specified
SYMBOL
PARAMETER
CONDITIONS
MIN.
TYP.
MAX.
UNIT
I
CES
Collector cut-off current
2
V
BE
= 0 V; V
CE
= V
CESMmax
-
-
1.0
mA
I
CES
V
BE
= 0 V; V
CE
= V
CESMmax
;
-
-
2.0
mA
T
j
= 125 C
I
EBO
Emitter cut-off current
V
EB
= 6.0 V; I
C
= 0 A
-
-
100
A
BV
EBO
Emitter-base breakdown voltage
I
B
= 1 mA
7.5
13.5
-
V
V
CEOsust
Collector-emitter sustaining voltage
I
B
= 0 A; I
C
= 100 mA;
800
-
-
V
L = 25 mH
V
CEsat
Collector-emitter saturation voltages I
C
= 5.0 A; I
B
= 1.25 A
-
-
3.0
V
V
BEsat
Base-emitter saturation voltage
I
C
= 5.0 A; I
B
= 1.25 A
0.85
0.94
1.03
V
h
FE
DC current gain
I
C
= 100 mA; V
CE
= 5 V
-
12
-
h
FE
I
C
= 5.0 A; V
CE
= 5 V
4.2
5.7
7.3
DYNAMIC CHARACTERISTICS
T
hs
= 25 C unless otherwise specified
SYMBOL
PARAMETER
CONDITIONS
TYP.
MAX.
UNIT
C
c
Collector capacitance
I
E
= 0 A; V
CB
= 10 V; f = 1 MHz
80
-
pF
Switching times (16 kHz line
I
Csat
= 5.0 A;I
B1
= 1.0 A
deflection circuit)
(I
B2
= -2.5 A)
t
s
Turn-off storage time
3.2
4.3
s
t
f
Turn-off fall time
0.35
0.48
s
Switching times (64 kHz line
I
Csat
= 4.0 A;I
B1
= 0.8 A
deflection circuit)
(I
B2
= -2.0 A)
t
s
Turn-off storage time
1.9
-
s
t
f
Turn-off fall time
0.17
-
s
2 Measured with half sine-wave voltage (curve tracer).
May 1998
2
Rev 1.000
Philips Semiconductors
Product specification
Silicon Diffused Power Transistor
BU4508AX
Fig.1. Test circuit for V
CEOsust
.
Fig.2. Oscilloscope display for V
CEOsust
.
Fig.3. Switching times waveforms (16 kHz).
Fig.4. Switching times definitions.
Fig.5. Switching times test circuit.
Fig.6. High and low DC current gain.
+ 50v
100-200R
Horizontal
Vertical
Oscilloscope
1R
6V
30-60 Hz
100R
ICsat
90 %
10 %
tf
ts
IB1
IC
IB
t
t
- IB2
VCE / V
min
VCEOsust
IC / mA
100
200
250
0
+ 150 v nominal
adjust for ICsat
Lc
Cfb
T.U.T.
LB
IBend
-VBB
IC
IB
VCE
ICsat
IB1
64us
26us
20us
t
t
t
TRANSISTOR
DIODE
IB2
0.001
0.01
0.1
1
10
1
10
100
VCE = 1V
Ths = 25 C
Ths = 85 C
hFE
IC / A
May 1998
3
Rev 1.000
Philips Semiconductors
Product specification
Silicon Diffused Power Transistor
BU4508AX
Fig.7. High and low DC current gain.
Fig.8. Typical collector-emitter saturation voltage.
Fig.9. Typical base-emitter saturation voltage.
Fig.10. Typical collector storage and fall time.
I
C
=5 A; T
j
= 85C; f = 16kHz
Fig.11. Normalised power dissipation.
PD% = 100
P
D
/P
D 25C
Fig.12. Transient thermal impedance.
0.001
0.01
0.1
1
10
1
10
100
hFE
IC / A
VCE = 5V
Ths = 25 C
Ths = 85 C
0
0.5
1
1.5
2
2.5
3
0
2
4
6
8
10
ts/tf / us
IB / A
ts
tf
ICsat = 5 A
Ths = 85 C
Freq = 16 kHz
0.1
1
10
100
0.01
0.1
1
10
Ths = 25 C
Ths = 85 C
IC/IB = 5
BU4508AF/X/Z
IC / A
VCEsat / V
0
20
40
60
80
100
120
140
Ths / C
PD%
Normalised Power Derating
120
110
100
90
80
70
60
50
40
30
20
10
0
with heatsink compound
0
0.5
1
1.5
2
2.5
3
0.6
0.7
0.8
0.9
1
1.1
1.2
IC = 5 A
IC = 4 A
VBEsat / V
IB / A
Ths = 25 C
Ths = 85 C
BU4508AF/X/Z
1.0E-07
1.0E-05
1.0E-03
1.0E-01
1.0E+01
0.001
0.01
0.1
1
10
0
0.2
0.1
0.05
0.02
0.5
BU4508AF
t / s
Zth K/W
D =
t
p
t
p
T
T
P
t
D
May 1998
4
Rev 1.000
Philips Semiconductors
Product specification
Silicon Diffused Power Transistor
BU4508AX
Fig.13. I
Csat
during normal running vs. frequency of
operation for optimum performance
0
20
40
60
80
100
0
2
4
6
8
10
Ic(sat) (A)
Frequency (kHz)
May 1998
5
Rev 1.000
Philips Semiconductors
Product specification
Silicon Diffused Power Transistor
BU4508AX
MECHANICAL DATA
Dimensions in mm
Net Mass: 5.88 g
Fig.14. SOT399; The seating plane is electrically isolated from all terminals.
Notes
1. Refer to mounting instructions for F-pack envelopes.
2. Epoxy meets UL94 V0 at 1/8".
4.5
16.0 max
0.7
10.0
5.1
27
max
18.1
min
4.5
2.2 max
1.1
0.4 M
5.45
5.45
25
25.1
3.0
25.7
5.8 max
3.3
0.9 max
2
3.3
22.5
max
May 1998
6
Rev 1.000
Philips Semiconductors
Product specification
Silicon Diffused Power Transistor
BU4508AX
DEFINITIONS
Data sheet status
Objective specification
This data sheet contains target or goal specifications for product development.
Preliminary specification This data sheet contains preliminary data; supplementary data may be published later.
Product specification
This data sheet contains final product specifications.
Limiting values
Limiting values are given in accordance with the Absolute Maximum Rating System (IEC 134). Stress above one
or more of the limiting values may cause permanent damage to the device. These are stress ratings only and
operation of the device at these or at any other conditions above those given in the Characteristics sections of
this specification is not implied. Exposure to limiting values for extended periods may affect device reliability.
Application information
Where application information is given, it is advisory and does not form part of the specification.
Philips Electronics N.V. 1998
All rights are reserved. Reproduction in whole or in part is prohibited without the prior written consent of the
copyright owner.
The information presented in this document does not form part of any quotation or contract, it is believed to be
accurate and reliable and may be changed without notice. No liability will be accepted by the publisher for any
consequence of its use. Publication thereof does not convey nor imply any license under patent or other
industrial or intellectual property rights.
LIFE SUPPORT APPLICATIONS
These products are not designed for use in life support appliances, devices or systems where malfunction of these
products can be reasonably expected to result in personal injury. Philips customers using or selling these products
for use in such applications do so at their own risk and agree to fully indemnify Philips for any damages resulting
from such improper use or sale.
May 1998
7
Rev 1.000
PDF 
ZIP