BF421
SMALL SIGNAL PNP TRANSISTOR
PRELIMINARY DATA
s
SILICON EPITAXIAL PLANAR PNP HIGH
VOLTAGE TRANSISTOR
s
TO-92 PACKAGE SUITABLE FOR
THROUGH-HOLE PCB ASSEMBLY
s
THE NPN COMPLEMENTARY TYPE IS
BF420
APPLICATIONS
s
VIDEO AMPLIFIER CIRCUITS (RGB
CATHODE CURRENT CONTROL)
s
TELEPHONE WIRELINE INTERFACE (HOOK
SWITCHES, DIALER CIRCUITS)
INTERNAL SCHEMATIC DIAGRAM
February 2003
ABSOLUTE MAXIMUM RATINGS
Symbol
Parameter
Value
Unit
V
CBO
Collector-Base Voltage (I
E
= 0)
-300
V
V
CEO
Collector-Emitter Voltage (I
B
= 0)
-300
V
V
EBO
Emitter-Base Voltage (I
C
= 0)
-5
V
I
C
Collector Current
-500
mA
I
CM
Collector Peak Current (t
p
< 5ms)
-600
mA
P
tot
Total Dissipation at T
C
= 25
o
C
830
mW
T
stg
Storage Temperature
-65 to 150
o
C
T
j
Max. Operating Junction Temperature
150
o
C
Ordering Code
Marking
Package / Shipment
BF421
BF421
TO-92 / Bulk
BF421-AP
BF421
TO-92 / Ammopack
TO-92
Bulk
TO-92
Ammopack
1/5
THERMAL DATA
R
thj-amb
R
thj-Case
Thermal Resistance Junction-Ambient Max
Thermal Resistance Junction-Case Max
150
50
o
C/W
o
C/W
ELECTRICAL CHARACTERISTICS (T
case
= 25
o
C unless otherwise specified)
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
I
CBO
Collector Cut-off
Current (I
E
= 0)
V
CB
= -200 V
V
CB
= -200 V T
C
= 150
o
C
V
CB
= -300 V
-10
-10
-100
nA
A
A
I
EBO
Emitter Cut-off Current
(I
C
= 0)
V
EB
= -5 V
-50
nA
V
(BR)CEO
Collector-Emitter
Breakdown Voltage
(I
B
= 0)
I
C
= -10 mA
-300
V
V
(BR)CBO
Collector-Base
Breakdown Voltage
(I
E
= 0)
I
C
= -10
A
-300
V
V
(BR)EBO
Emitter-Base
Breakdown Voltage
(I
C
= 0)
I
E
= -100
A
-5
V
V
CE(sat)
Collector-Emitter
Saturation Voltage
I
C
= -30 mA I
B
= -5 mA
-0.6
V
V
BE(sat)
Base-Emitter
Saturation Voltage
I
C
= -30 mA I
B
= -5 mA
-1.2
V
h
FE
DC Current Gain
I
C
= -25 mA V
CE
= -20 V
50
f
T
Transition Frequency
I
C
= -10 mA V
CE
= -10 V f =100MHz
60
MHz
C
RE
Reverse Capacitance
I
E
= 0 V
CB
= -30 V f = 1MHz
1.6
pF
Pulsed: Pulse duration
300
s, duty cycle
2 %
BF421
2/5
DIM.
mm
inch
MIN.
TYP.
MAX.
MIN.
TYP.
MAX.
A
4.32
4.95
0.170
0.195
b
0.36
0.51
0.014
0.020
D
4.45
4.95
0.175
0.194
E
3.30
3.94
0.130
0.155
e
2.41
2.67
0.095
0.105
e1
1.14
1.40
0.045
0.055
L
12.70
15.49
0.500
0.609
R
2.16
2.41
0.085
0.094
S1
1.14
1.52
0.045
0.059
W
0.41
0.56
0.016
0.022
V
4 degree
6 degree
4 degree
6 degree
TO-92 MECHANICAL DATA
BF421
3/5
DIM.
mm
inch
MIN.
TYP.
MAX.
MIN.
TYP.
MAX.
A1
4.80
0.189
T
3.80
0.150
T1
1.60
0.063
T2
2.30
0.091
d
0.48
0.019
P0
12.50
12.70
12.90
0.492
0.500
0.508
P2
5.65
6.35
7.05
0.222
0.250
0.278
F1,F2
2.44
2.54
2.94
0.096
0.100
0.116
delta H
-2.00
2.00
-0.079
0.079
W
17.50
18.00
19.00
0.689
0.709
0.748
W0
5.70
6.00
6.30
0.224
0.236
0.248
W1
8.50
9.00
9.25
0.335
0.354
0.364
W2
0.50
0.020
H
18.50
20.50
0.728
0.807
H0
15.50
16.00
16.50
0.610
0.630
0.650
H1
25.00
0.984
D0
3.80
4.00
4.20
0.150
0.157
0.165
t
0.90
0.035
L
11.00
0.433
I1
3.00
0.118
delta P
-1.00
1.00
-0.039
0.039
TO-92 AMMOPACK SHIPMENT (Suffix"-AP") MECHANICAL DATA
BF421
4/5
Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences
of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is
granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specification mentioned in this publication are
subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products
are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics.
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2003 STMicroelectronics Printed in Italy All Rights Reserved
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BF421
5/5
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