CYStech Electronics Corp.
Spec. No. : C234A3-A
Issued Date : 2004.03.02
Revised Date : 2004.10.18
Page No. : 1/4
BF420A3/S CYStek Product Specification
NPN Epitaxial Planar Transistor
BF420A3/S
Description
• NPN high voltage transistors in a TO-92 plastic package.
• Complementary to BF421A3/S.
• Pb-free package is available
Features
• Low feedback capacitance.
Applications
• Class-B video output stages in color television and professional monitor equipment.
Symbol Outline
Absolute Maximum Ratings (Ta=25°C)
Parameter Symbol Conditions Min Max Unit
Collector-Base Voltage VCBO Open emitter 300 V
Collector-Emitter Voltage VCEO Open base 300 V
Emitter-Base Voltage VEBO Open collector 5 V
Collector Current (DC) IC 50 mA
Peak Collector Current ICM 100 mA
Peak Base Current IBM 50 mA
Power Dissipation; Pd Tamb≤25℃ ; Note 830 mW
Junction Temperature Tj 150 °C
Storage Temperature Tstg -65 +150 °C
Operating Ambient Temperature Tamb -65 +150 °C
Note : Transistor mounted on a printed-circuit board.
BF420A3/S
TO-92
B：Base
C：Collector
E：Emitter E C B
CYStech Electronics Corp.
Spec. No. : C234A3-A
Issued Date : 2004.03.02
Revised Date : 2004.10.18
Page No. : 2/4
BF420A3/S CYStek Product Specification
Characteristics (Ta=25°C)
Symbol Min. Typ. Max. Unit Test Conditions
BVCBO 300 - - V IC=100µA
BVCEO 300 - - V IC=1mA
BVEBO 5 - - V IE=10µA
- - 10 nA IE=0, VCB=200V
ICBO - - 10 µA
IE=0, VCB=200V, Tj=150℃
IEBO - - 50 nA IC=0, VEB=5V
*VCE(sat) - - 0.6 V IC=30mA, IB=5mA
*hFE 50 - - - VCE=20V, IC=25mA
Cre - - 1.6 pF IC=iC=0, VCE=30V, f=1MHz
fT 60 - - MHz VCE=10V, IC=10mA, f=100MHz
*Pulse Test: Pulse Width ≤380µs, Duty Cycle≤2%
Thermal Characteristics
Symbol Parameter Conditions Value Unit
RthJA Thermal resistance from junction to ambient Note 150 K/W
Note : Transistor mounted on a printed-circuit board
Ordering Information
Device Package Shipping
BF420A3 TO-92 2000 pcs / tape & box
BF420A3S TO-92
(Pb-free)
2000 pcs / tape & box
CYStech Electronics Corp.
Spec. No. : C234A3-A
Issued Date : 2004.03.02
Revised Date : 2004.10.18
Page No. : 3/4
BF420A3/S CYStek Product Specification
Characteristic Curves
Current Gain vs Collector Current
10
100
1000
1 10 100
Collector Current---IC(mA)
Current Gain---HFE
VCE = 5V
VCE = 10
V
VCE = 20V
Saturation Voltage vs Collector Current
10
100
1000
10000
1 10 100
Collector Current---IC(mA)
Saturation Voltage---(mV)
VCE(SAT) @ IC = 10IB
VCE(SAT) @ IC = 20IB
Saturation Voltage vs Collector Current
100
1000
1 10 100
Collector Current---IC(mA)
Saturation Voltage---(mV)
VBE(SAT) @ IC =10IB
Power Derating Curve
0
100
200
300
400
500
600
700
800
900
0 50 100 150 200
Ambient Temperature---TA(℃)
Power Dissipation---PD(mW)
CYStech Electronics Corp.
Spec. No. : C234A3-A
Issued Date : 2004.03.02
Revised Date : 2004.10.18
Page No. : 4/4
BF420A3/S CYStek Product Specification
TO-92 Dimension
*: Typical
Inches Millimeters Inches Millimeters
DIM Min. Max. Min. Max.
DIM Min. Max. Min. Max.
A 0.1704 0.1902 4.33 4.83 G 0.0142 0.0220 0.36 0.56
B 0.1704 0.1902 4.33 4.83 H - *0.1000 - *2.54
C 0.5000 - 12.70 - I - *0.0500 - *1.27
D 0.0142 0.0220 0.36 0.56 α1 - *5° - *5°
E - *0.0500 - *1.27 α2 - *2° - *2°
F 0.1323 0.1480 3.36 3.76 α3 - *2° - *2°
Notes: 1.Controlling dimension: millimeters.
2.Maximum lead thickness includes lead finish thickness, and minimum lead thickness is the minimum thickness of base material.
3.If there is any question with packing specification or packing method, please contact your local CYStek sales office.
Material:
• Lead: 42 Alloy ; solder plating
• Mold Compound: Epoxy resin family, flammability solid burning class: UL94V-0
Important Notice:
• All rights are reserved. Reproduction in whole or in part is prohibited without the prior written approval of CYStek.
• CYStek reserves the right to make changes to its products without notice.
• CYStek semiconductor products are not warranted to be suitable for use in Life-Support Applications, or systems.
• CYStek assumes no liability for any consequence of customer product design, infringement of patents, or application assistance.
BF420
Marking:
31
A
D
B
C
Iα1
E
F
α2
α3
G
H
2
Style: Pin 1.Emitter 2.Collector 3.Base
3-Lead TO-92 Plastic Package
CYStek Packa
g
e Code:
A
3
