BF257
BF258-BF259
October 1988
HIGHVOLTAGE VIDEO AMPLIFIERS
DESCRIPTION
The BF257, BF258 and BF259 are silicon planar
epitaxial NPN transistors in Jedec TO-39 metal
case.They areparticularly designedforvideooutput
stages in CTV and MTV sets, class A audio output
stagesand drivers for horizontal deflection circuits.
ABSOLUTE MAXIMUM RATINGS
Value
Symbol Parameter BF257 BF258 BF259 Unit
VCBO Collector-base Voltage (IE= 0) 160 250 300 V
VCEO Collector-emitter Voltage (IB= 0) 160 250 300 V
VEBO Emitter-base Voltage (IC=0) 5 V
ICCollector Current 100 mA
ICM Collector Peak Current 200 mA
Ptot Total Power Dissipation at Tamb ≤50 °C5W
T
stg Storage Temperature – 55 to 200 °C
TjJunction Temperature 200 °C
INTERNAL SCHEMATIC DIAGRAM
TO-39
1/5
ELECTRICAL CHARACTERISTICS (Tamb =25°C unless otherwise specified)
Symbol Parameter Test Conditions Min. Typ. Max. Unit
ICBO Collector Cutoff Current
(IE=0) for BF257
for BF258
for BF259
VCB = 100 V
VCB = 200 V
VCB = 250 V
50
50
50
nA
nA
nA
V(BR) CBO Collector-base
Breakdown Voltage
(IE=0) IC=100µAfor BF257
for BF258
for BF259
160
250
300
V
V
V
V(BR)CEO* Collector-emitter
Breakdown Voltage
(IB=0) IC=10mA for BF257
for BF258
for BF259
160
250
300
V
V
V
V(BR) EBO Emittter-base
Breakdown Voltage
(IC=0) IE=100µA5 V
V
CE (sat)* Collector-emitter
Saturation Voltage IC=30mA IB=6mA 1 V
hFE* DC Current Gain IC=30mA V
CE =10V 25
f
TTransition Frequency IC=15mA V
CE =10V 90 MHz
C
re Reverse Capacitance IC=0
f=1MHz V
CE =30V 3pF
* Pulsed : pulse duration = 300 µs, duty cycle = 1 %.
DC Current Gain.
THERMAL DATA
Rth j-case
Rth j-amb
Thermal Resistance Junction-case
Thermal Resistance Junction-ambient Max
Max 30
175 °C/W
°C/W
BF257-BF258-BF259
2/5
Collector Cutoff Current. Collector-base Capacitance.
Transition Frequency. Power Rating Chart.
SafeOperating Area.
BF257-BF258-BF259
3/5
DIM. mm inch
MIN. TYP. MAX. MIN. TYP. MAX.
A 12.7 0.500
B 0.49 0.019
D 6.6 0.260
E 8.5 0.334
F 9.4 0.370
G 5.08 0.200
H 1.2 0.047
I 0.9 0.035
L45
o
(typ.)
L
G
I
DA
F
E
B
H
TO39 MECHANICAL DATA
P008B
BF257-BF258-BF259
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Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsability for the
consequences of useof such information nor for any infringementof patents orother rights of third partieswhich mayresults from its use. No
license is granted by implication or otherwiseunder anypatent or patent rights of SGS-THOMSON Microelectronics.Specificationsmentioned
in this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied.
SGS-THOMSON Microelectronicsproducts arenot authorizedfor use as criticalcomponents inlife supportdevices or systems withoutexpress
written approval of SGS-THOMSON Microelectonics.
1994 SGS-THOMSON Microelectronics - All Rights Reserved
SGS-THOMSON Microelectronics GROUP OF COMPANIES
Australia - Brazil - France- Germany - Hong Kong -Italy - Japan - Korea - Malaysia - Malta - Morocco- The Netherlands -
Singapore -Spain - Sweden- Switzerland -Taiwan - Thailand - UnitedKingdom - U.S.A
BF257-BF258-BF259
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