DATA SH EET
Product specification
Supersedes data of April 1995
File under Discrete Semiconductors, SC07
1996 Jul 30
DISCRETE SEMICONDUCTORS
BF245A; BF245B; BF245C
N-channel silicon field-effect
transistors
1996 Jul 30 2
Philips Semiconductors Product specification
N-channel silicon field-effect transistors BF245A; BF245B; BF245C
FEATURES
•Interchangeability of drain and source connections
•Frequencies up to 700 MHz.
APPLICATIONS
•LF, HF and DC amplifiers.
DESCRIPTION
General purpose N-channel symmetrical junction
field-effect transistors in a plastic TO-92 variant package.
CAUTION
The device is supplied in an antistatic package. The
gate-source input must be protected against static
discharge during transport or handling.
PINNING
PIN SYMBOL DESCRIPTION
1 d drain
2 s source
3 g gate
Fig.1 Simplified outline (TO-92 variant)
and symbol.
handbook, halfpage
1
3
2
MAM257
s
d
g
QUICK REFERENCE DATA
SYMBOL PARAMETER CONDITIONS MIN. TYP. MAX. UNIT
VDS drain-source voltage −−±30 V
VGSoff gate-source cut-off voltage ID= 10 nA; VDS = 15 V −0.25 − −8 V
VGSO gate-source voltage open drain −−−30 V
IDSS drain current VDS = 15 V; VGS = 0
BF245A 2 −6.5 mA
BF245B 6 −15 mA
BF245C 12 −25 mA
Ptot total power dissipation Tamb = 75 °C−−300 mW
yfsforward transfer admittance VDS = 15 V; VGS = 0;
f = 1 kHz; Tamb = 25 °C3−6.5 mS
Crs reverse transfer capacitance VDS = 20 V; VGS =−1 V;
f = 1 MHz; Tamb = 25 °C−1.1 −pF
1996 Jul 30 3
Philips Semiconductors Product specification
N-channel silicon field-effect transistors BF245A; BF245B; BF245C
LIMITING VALUES
In accordance with the Absolute Maximum Rating System (IEC 134).
Note
1. Device mounted on a printed-circuit board, minimum lead length 3 mm, mounting pad for drain lead minimum
10 mm ×10 mm.
THERMAL CHARACTERISTICS
STATIC CHARACTERISTICS
Tj= 25 °C; unless otherwise specified.
Note
1. Measured under pulse conditions: tp= 300 µs; δ ≤ 0.02.
SYMBOL PARAMETER CONDITIONS MIN. MAX. UNIT
VDS drain-source voltage − ±30 V
VGDO gate-drain voltage open source − −30 V
VGSO gate-source voltage open drain − −30 V
IDdrain current −25 mA
IGgate current −10 mA
Ptot total power dissipation up to Tamb = 75 °C; −300 mW
up to Tamb = 90 °C; note 1 −300 mW
Tstg storage temperature −65 +150 °C
Tjoperating junction temperature −150 °C
SYMBOL PARAMETER CONDITIONS VALUE UNIT
Rth j-a thermal resistance from junction to ambient in free air 250 K/W
thermal resistance from junction to ambient 200 K/W
SYMBOL PARAMETER CONDITIONS MIN. MAX. UNIT
V(BR)GSS gate-source breakdown voltage IG=−1µA; VDS = 0 −30 −V
VGSoff gate-source cut-off voltage ID= 10 nA; VDS = 15 V −0.25 −8.0 V
VGS gate-source voltage ID= 200 µA; VDS = 15 V
BF245A −0.4 −2.2 V
BF245B −1.6 −3.8 V
BF245C −3.2 −7.5 V
IDSS drain current VDS = 15 V; VGS = 0; note 1
BF245A 2 6.5 mA
BF245B 6 15 mA
BF245C 12 25 mA
IGSS gate cut-off current VGS =−20 V; VDS = 0 − −5 nA
VGS =−20 V; VDS = 0; Tj= 125 °C− −0.5 µA
1996 Jul 30 4
Philips Semiconductors Product specification
N-channel silicon field-effect transistors BF245A; BF245B; BF245C
DYNAMIC CHARACTERISTICS
Common source; Tamb = 25 °C; unless otherwise specified.
SYMBOL PARAMETER CONDITIONS MIN. TYP. MAX. UNIT
Cis input capacitance VDS = 20 V; VGS =−1 V; f = 1 MHz −4−pF
Crs reverse transfer capacitance VDS = 20 V; VGS =−1 V; f = 1 MHz −1.1 −pF
Cos output capacitance VDS = 20 V; VGS =−1 V; f = 1 MHz −1.6 −pF
gis input conductance VDS = 15 V; VGS = 0; f = 200 MHz −250 − µS
gos output conductance VDS = 15 V; VGS = 0; f = 200 MHz −40 − µS
yfsforward transfer admittance VDS = 15 V; VGS = 0; f = 1 kHz 3 −6.5 mS
VDS = 15 V; VGS = 0; f = 200 MHz −6−mS
yrsreverse transfer admittance VDS = 15 V; VGS = 0; f = 200 MHz −1.4 −mS
yosoutput admittance VDS = 15 V; VGS = 0; f = 1 kHz −25 − µS
fgfs cut-off frequency VDS = 15 V; VGS = 0; gfs = 0.7 of its
value at 1 kHz −700 −MHz
F noise figure VDS = 15 V; VGS = 0; f = 100 MHz;
RG= 1 kΩ (common source);
input tuned to minimum noise
−1.5 −dB
handbook, halfpage
−10
−10−3
−10−2
−10−1
−1
150500
MGE785
100
typ
Tj (°C)
IGSS
(nA)
Fig.2 Gate leakage current as a function of
junction temperature; typical values.
VDS = 0; VGS =−20 V.
Fig.3 Transfer characteristics for BF245A;
typical values.
handbook, halfpage
VGS (V)
ID
(mA)
6
0−4 0−2
MGE789
5
4
3
2
1
VDS = 15 V; Tj= 25 °C.
1996 Jul 30 5
Philips Semiconductors Product specification
N-channel silicon field-effect transistors BF245A; BF245B; BF245C
handbook, halfpage
VDS (V)
ID
(mA)
6
00 2010
MBH555
5
4
3
2
1
VGS = 0 V
−0.5 V
−1 V
−1.5 V
Fig.4 Output characteristics for BF245A;
typical values.
VDS = 15 V; Tj= 25 °C.
Fig.5 Transfer characteristics for BF245B;
typical values.
VDS = 15 V; Tj= 25 °C.
handbook, halfpage
VGS (V)
ID
(mA)
15
0−4 0−2
MGE787
10
5
handbook, halfpage
VDS (V)
ID
(mA)
15
00 2010
MBH553
10
5
VGS = 0 V
−0.5 V
−1 V
−1.5 V
−2 V
−2.5 V
Fig.6 Output characteristics for BF245B;
typical values.
VDS = 15 V; Tj= 25 °C.
Fig.7 Transfer characteristics for BF245C;
typical values.
handbook, halfpage
VGS (V)
ID
(mA)
30
0
−10 0−5
MGE788
20
10
VDS = 15 V; Tj= 25 °C.
1996 Jul 30 6
Philips Semiconductors Product specification
N-channel silicon field-effect transistors BF245A; BF245B; BF245C
handbook, halfpage
VDS (V)
ID
(mA)
30
00 2010
MBH554
20
10
VGS = 0 V
−1 V
−2 V
−3 V
−4 V
Fig.8 Output characteristics for BF245C;
typical values.
VDS = 15 V; Tj= 25 °C.
Fig.9 Drain current as a function of junction
temperature; typical values for BF245A.
VDS = 15 V.
handbook, halfpage
00 50 150
Tj (°C)
4
ID
(mA)
3
1
2
MGE775
100
−0.5 V
VGS = 0 V
−1.5 V
−1 V
Fig.10 Drain current as a function of junction
temperature; typical values for BF245B.
handbook, halfpage
00 50 150
15
5
10
MGE776
100 Tj (°C)
ID
(mA)
VGS = 0 V
−2 V
−1 V
VDS = 15 V.
Fig.11 Drain current as a function of junction
temperature; typical values for BF245C.
VDS = 15 V.
handbook, halfpage
0 50 150
20
0
MGE779
100
4
8
12
16
Tj (°C)
ID
(mA)
VGS = 0 V
−4 V
−2 V
1996 Jul 30 7
Philips Semiconductors Product specification
N-channel silicon field-effect transistors BF245A; BF245B; BF245C
Fig.12 Input admittance; typical values.
handbook, halfpage
MGE778
103
102
10
1
102
10
1
10−1
10 102103
gis
(µA/V) bis
(mA/V)
f (MHz)
bis
gis
VDS = 15 V; VGS = 0; Tamb = 25 °C.
Fig.13 Common source reverse admittance as a
function of frequency; typical values.
handbook, halfpage
MGE780
104
103
102
10
10
1
10−1
10−2
10 102103
brs
(µA/V) Crs
(pF)
f (MHz)
brs
Crs
VDS = 15 V; VGS = 0; Tamb = 25 °C.
Fig.14 Common-source forward transfer admittance
as a function of frequency; typical values.
VDS = 15 V; VGS = 0; Tamb = 25 °C.
handbook, halfpage
10
0
MGE782
10 102103
2
4
6
8
gfs,
−bfs
(mA/V)
f (MHz)
−bfs
gfs
Fig.15 Common-source output admittance as a
function of frequency; typical values.
VDS = 15 V; VGS = 0; Tamb = 25 °C.
handbook, halfpage
MGE783
103
102
10
1
10
1
10−1
10−2
10 102103
gos
(µA/V) bos
(mA/V)
f (MHz)
bos
gos
1996 Jul 30 8
Philips Semiconductors Product specification
N-channel silicon field-effect transistors BF245A; BF245B; BF245C
Fig.16 Input capacitance as a function of
gate-source voltage; typical values.
VDS = 20 V; f = 1 MHz; Tamb = 25 °C.
handbook, halfpage
0
6
4
2
0−2−10
MGE777
−4−6−8
VGS (V)
Cis
(pF)
typ
Fig.17 Reverse transfer capacitance as a function
of gate-source voltage; typical values.
VDS = 20 V; f = 1 MHz; Tamb = 25 °C.
handbook, halfpage
0−10
1.5
0.5
MGE781
1
Crs
(pF)
−2−4−6−8
VGS (V)
typ
Fig.18 Forward transfer admittance as a function of
drain current; typical values.
handbook, halfpage
8
6
0
MGE791
4
2
|yfs|
(mA/V)
ID (mA)
020
10 155
BF245A
BF245B BF245C
VDS = 15 V; f = 1 kHz; Tamb = 25 °C.
Fig.19 Gate-source cut-off voltage as a function of
drain current; typical values.
VDS = 15 V; Tj= 25 °C.
handbook, halfpage
0 10 30
−10
−0
MGE784
20
−2
−4
−6
−8
BF245A
IDSS at VGS = 0 (mA)
VGSoff
at ID = 10 nA
(V)
BF245B
BF245C
1996 Jul 30 9
Philips Semiconductors Product specification
N-channel silicon field-effect transistors BF245A; BF245B; BF245C
Fig.20 Drain-source on-state resistance as a
function of gate-source voltage;
typical values.
VDS = 0; f = 1 kHz; Tamb = 25 °C.
handbook, halfpage
10
3
10
−1
1
10
10
2
−4−2−10
MGE790
−3
RDSon
(kΩ)
BF245A BF245B BF245C
VGS (V)
Fig.21 Noise figure as a function of frequency;
typical values.
VDS = 15 V; VGS = 0; RG= 1 kΩ; Tamb = 25 °C.
Input tuned to minimum noise.
handbook, halfpage
0
3
MGE786
1 10
typ
102103
1
2
F
(dB)
f (MHz)
1996 Jul 30 10
Philips Semiconductors Product specification
N-channel silicon field-effect transistors BF245A; BF245B; BF245C
PACKAGE OUTLINE
Fig.22 TO-92 variant.
handbook, full pagewidth
MBC015 - 1
2.54
4.8
max
4.2 max
0.66
0.56
1
2
3
5.2 max 12.7 min
2.5 max (1)
0.48
0.40
0.40
min
1.7
1.4
Dimensions in mm.
(1) Terminal dimensions within this zone are uncontrolled.
1996 Jul 30 11
Philips Semiconductors Product specification
N-channel silicon field-effect transistors BF245A; BF245B; BF245C
DEFINITIONS
LIFE SUPPORT APPLICATIONS
These products are not designed for use in life support appliances, devices, or systems where malfunction of these
products can reasonably be 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.
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 given are 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 the 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.
