FEATURES
MECHANICAL DATA
Case: TO-92 Plastic Package
Weight: approx. 0.18 g
MAXIMUM RATINGS AND ELECTRICAL CHARACTERISTICS
Small Signal Transistors (NPN)
C
B
E
.181 (4.6)
mi
n. .492
(
12.5)
.181 (
4
.6)
.142 (3.6)
Dimensions in inches and (millimeters)
TO-92
Ratings at 25 C
ambient temperature unless otherwise specified
.098 (2.5)
max.
.022 (0.55)
4/98
BF420, BF422
Symbol
Value
Unit
Collector-Base Voltage
BF420
BF422
V
CBO
V
CBO
300
250
V
V
Collector-Emitter Voltage
BF422
V
CEO
250
V
Collector-Emitter Voltage
BF420
V
CER
300
V
Emitter-Base Voltage
V
EBO
5
V
Collector Current
I
C
50
mA
Peak Collector Current
I
CM
100
mA
Power Dissipation at T
amb
= 25 C
P
tot
830
1)
mW
Junction Temperature
T
j
150
C
Storage Temperature Range
T
S
65 to +150
C
1)
Valid provided that leads are kept at ambient temperature at a distance of 2 mm from case
NPN Silicon Epitaxial Planar Transistors
especially suited for application in class-B
video output stages of TV receivers and
monitors.
As complementary types, the PNP
transistors BF421 and BF423 are
recommended
ELECTRICAL CHARACTERISTICS
Ratings at 25 C
ambient temperature unless otherwise specified
Symbol
Min.
Typ.
Max.
Unit
Collector-Base Breakdown Voltage
BF420
at I
C
= 100
A, I
B
= 0
BF422
V
(BR)CBO
V
(BR)CBO
300
250
V
V
Collector-Emitter Breakdown Voltage
BF422
at I
C
= 10
m
A, I
E
= 0
V
(BR)CEO
250
V
Collector-Emitter Breakdown Voltage
BF420
at R
BE
= 2.7 k
, I
C
= 10 mA
V
(BR)CER
300
V
Emitter-Base Breakdown Voltage
at I
E
= 100
A, I
B
= 0
V
(BR)EBO
5
V
Collector-Base Cutoff Current
at V
CB
= 200 V, I
E
= 0
I
CBO
10
nA
Collector-Emitter Cutoff Current
at R
BE
= 2.7 k
, V
CE
= 250 V
at R
BE
= 2.7 k
, V
CE
= 200 V, T
j
= 150 C
I
CER
I
CER
50
10
nA
A
Collector Saturation Voltage
at I
C
= 30 mA, I
B
= 5 mA
V
CEsat
0.6
V
DC Current Gain
at V
CE
= 20 V, I
C
= 25 mA
h
FE
50
Gain-Bandwidth Product
at V
CE
= 10 V, I
C
= 10 mA
f
T
60
MHz
Feedback Capacitance
at V
CE
= 30 V, I
C
= 0, f = 1 MHz
C
re
1.6
pF
Thermal Resistance Junction to Ambient Air
R
thJA
150
1)
K/W
1)
Valid provided that leads are kept at ambient temperature at a distance of 2 mm from case
BF420, BF422
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