Philips BF245C, BF245B, BF245A Datasheet

DISCRETE SEMICONDUCTORS

DATA SH EET

BF245A; BF245B; BF245C

N-channel silicon field-effect
transistors

Product specification
Supersedes data of April 1995
File under Discrete Semiconductors, SC07

1996 Jul 30

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.

PINNING

PIN SYMBOL DESCRIPTION

1 d drain
2 s source

APPLICATIONS

3 g gate

• 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.

handbook, halfpage

Fig.1 Simplified outline (TO-92 variant)

1

2

3

and symbol.

g

MAM257

QUICK REFERENCE DATA

SYMBOL PARAMETER CONDITIONS MIN. TYP. MAX. UNIT

V

DS

V

GSoff

V

GSO

I

DSS

drain-source voltage −−±30 V
gate-source cut-off voltage ID= 10 nA; VDS=15V −0.25 −−8V
gate-source voltage open drain −−−30 V
drain current VDS= 15 V; VGS=0

BF245A 2 − 6.5 mA
BF245B 6 − 15 mA
BF245C 12 − 25 mA

P

tot

 forward transfer admittance VDS= 15 V; VGS=0;

y

fs

C

rs

total power dissipation T

reverse transfer capacitance VDS= 20 V; VGS= −1V;

=75°C −−300 mW

amb

3 − 6.5 mS

f = 1 kHz; T

amb

=25°C

− 1.1 − pF

f = 1 MHz; T

amb

=25°C

d
s

1996 Jul 30 2

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).

SYMBOL PARAMETER CONDITIONS MIN. MAX. UNIT

V

DS

V

GDO

V

GSO

I

D

I

G

P

tot

T

stg

T

j

Note

1. Device mounted on a printed-circuit board, minimum lead length 3 mm, mounting pad for drain lead minimum
10 mm × 10 mm.

drain-source voltage −±30 V
gate-drain voltage open source −−30 V
gate-source voltage open drain −−30 V
drain current − 25 mA
gate current − 10 mA
total power dissipation up to T

up to T

=75°C; − 300 mW

amb

=90°C; note 1 − 300 mW

amb

storage temperature −65 +150 °C
operating junction temperature − 150 °C

THERMAL CHARACTERISTICS

SYMBOL PARAMETER CONDITIONS VALUE UNIT

R

th j-a

thermal resistance from junction to ambient in free air 250 K/W
thermal resistance from junction to ambient 200 K/W

STATIC CHARACTERISTICS

T

=25°C; unless otherwise specified.

j

SYMBOL PARAMETER CONDITIONS MIN. MAX. UNIT

V

(BR)GSS

V

GSoff

V

GS

gate-source breakdown voltage IG= −1 µA; VDS=0 −30 − V
gate-source cut-off voltage ID= 10 nA; VDS=15V −0.25 −8.0 V
gate-source voltage ID= 200 µA; VDS=15V

BF245A −0.4 −2.2 V
BF245B −1.6 −3.8 V
BF245C −3.2 −7.5 V

I

DSS

drain current VDS=15V; VGS= 0; note 1

BF245A 2 6.5 mA
BF245B 6 15 mA
BF245C 12 25 mA

I

GSS

gate cut-off current VGS= −20 V; VDS=0 −−5nA

= −20 V; VDS= 0; Tj= 125 °C −−0.5 µA

V

GS

Note

1. Measured under pulse conditions: t

= 300 µs; δ≤0.02.

p

1996 Jul 30 3

Philips Semiconductors Product specification

N-channel silicon field-effect transistors BF245A; BF245B; BF245C

DYNAMIC CHARACTERISTICS

Common source; T

SYMBOL PARAMETER CONDITIONS MIN. TYP. MAX. UNIT

C

is

C

rs

C

os

g

is

g

os

 forward transfer admittance VDS=15V;VGS= 0; f = 1 kHz 3 − 6.5 mS

y

fs

 reverse transfer admittance VDS=15V;VGS= 0; f = 200 MHz − 1.4 − mS

y

rs

 output admittance VDS=15V;VGS=0;f=1kHz − 25 −µS

y

os

f

gfs

input capacitance VDS= 20 V; VGS= −1 V; f = 1 MHz − 4 − pF
reverse transfer capacitance VDS= 20 V; VGS= −1 V; f = 1 MHz − 1.1 − pF
output capacitance VDS= 20 V; VGS= −1 V; f = 1 MHz − 1.6 − pF
input conductance VDS=15V;VGS= 0; f = 200 MHz − 250 −µS
output conductance VDS=15V;VGS= 0; f = 200 MHz − 40 −µS

cut-off frequency VDS=15V;VGS=0;gfs= 0.7 of its

F noise figure V

=25°C; unless otherwise specified.

amb

V

DS

value at 1 kHz

DS

RG=1kΩ (common source);
input tuned to minimum noise

=15V;VGS= 0; f = 200 MHz − 6 − mS

− 700 − MHz

=15V;VGS= 0; f = 100 MHz;

− 1.5 − dB

−10

handbook, halfpage

I



GSS
(nA)

−1

−1

−10

−2

−10

−3

−10

VDS= 0; VGS= −20V.

typ

100

Fig.2 Gate leakage current as a function of

junction temperature; typical values.

Tj (°C)

MGE785

handbook, halfpage

150500

6

I

D

(mA)

5

4

3

2

1

0

−40−2

VDS= 15 V; Tj=25°C.

VGS (V)

MGE789

Fig.3 Transfer characteristics for BF245A;

typical values.

1996 Jul 30 4