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DISCRETE SEMICONDUCTORS
DATA SH EET
BF904; BF904R
N-channel dual gate MOS-FETs
Product specification
Supersedes data of 1997 Sep 05
1999 May 17
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Philips Semiconductors Product specification
N-channel dual gate MOS-FETs BF904; BF904R
FEATURES
• Specially designed for use at 5 V supply voltage
• Short channel transistor with high transfer admittance to
input capacitance ratio
• Low noise gain controlled amplifier up to 1 GHz
• Superior cross-modulation performance during AGC.
APPLICATIONS
• VHF and UHF applications with 3 to 7 V supply voltage
such as television tuners and professional
communications equipment.
DESCRIPTION
Enhancement type field-effect transistor in a plastic
microminiature SOT143B and SOT143R package. The
transistor consists of an amplifier MOS-FET with source
handbook, halfpage
43
d
and substrate interconnected and an internal bias circuit to
ensure good cross-modulation performance during AGC.
CAUTION
This product is supplied in anti-static packing to
prevent damage caused by electrostatic discharge
during transport and handling. For further information,
refer to Philips specs.: SNW-EQ-608, SNW-FQ-302A
and SNW-FQ-302B.
PINNING
PIN SYMBOL DESCRIPTION
1 s, b source
2 d drain
3g
4g
handbook, halfpage
34
gate 2
2
gate 1
1
d
g
2
g
1
21
Top view
BF904 marking code: M04.
MAM124
Fig.1 Simplified outline (SOT143B) and symbol.
s,b
12
Top view
BF904R marking code: M06.
MAM125 - 1
Fig.2 Simplified outline (SOT143R) and symbol.
g
2
g
1
QUICK REFERENCE DATA
SYMBOL PARAMETER CONDITIONS MIN. TYP. MAX. UNIT
V
DS
I
D
P
tot
T
j
forward transfer admittance 22 25 30 mS
y
fs
C
ig1-s
C
rs
drain-source voltage −−7V
drain current −−30 mA
total power dissipation −−200 mW
operating junction temperature −−150 °C
input capacitance at gate 1 − 2.2 2.6 pF
reverse transfer capacitance f = 1 MHz − 25 35 fF
F noise figure f = 800 MHz − 2 − dB
s,b
1999 May 17 2
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Philips Semiconductors Product specification
N-channel dual gate MOS-FETs BF904; BF904R
LIMITING VALUES
In accordance with the Absolute Maximum Rating System (IEC 134).
SYMBOL PARAMETER CONDITIONS MIN. MAX. UNIT
V
DS
I
D
I
G1
I
G2
P
tot
T
stg
T
j
Note
1. Device mounted on a printed-circuit board.
drain-source voltage − 7V
drain current − 30 mA
gate 1 current −±10 mA
gate 2 current −±10 mA
total power dissipation see Fig.3
BF904 T
BF904R T
≤ 50 °C; note 1 − 200 mW
amb
≤ 40 °C; note 1 − 200 mW
amb
storage temperature −65 +150 °C
operating junction temperature − 150 °C
250
handbook, halfpage
P
tot
(mW)
200
150
100
50
0
0 50 100 150 200
BF904
BF904R
T
Fig.3 Power derating curves.
amb
MRA770
o
( C)
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Philips Semiconductors Product specification
N-channel dual gate MOS-FETs BF904; BF904R
THERMAL CHARACTERISTICS
SYMBOL PARAMETER CONDITIONS VALUE UNIT
R
th j-a
R
th j-s
Notes
1. Device mounted on a printed-circuit board.
is the temperature at the soldering point of the source lead.
2. T
s
STATIC CHARACTERISTICS
Tj=25°C unless otherwise specified.
thermal resistance from junction to ambient note 1
BF904 500 K/W
BF904R 550 K/W
thermal resistance from junction to soldering point note 2
BF904 T
BF904R T
=92°C 290 K/W
s
=78°C 360 K/W
s
SYMBOL PARAMETER CONDITIONS MIN. MAX. UNIT
V
(BR)G1-SS
V
(BR)G2-SS
V
(F)S-G1
V
(F)S-G2
V
G1-S(th)
V
G2-S(th)
I
DSX
gate 1-source breakdown voltage V
gate 2-source breakdown voltage V
forward source-gate 1 voltage V
forward source-gate 2 voltage V
gate 1-source threshold voltage V
gate 2-source threshold voltage V
drain-source current V
G2-S=VDS
G1-S=VDS
G2-S=VDS
G1-S=VDS
G2-S
G1-S=VDS
G2-S
= 0; I
= 0; I
= 0; I
= 0; I
= 10 mA 6 15 V
G1-S
= 10 mA 6 15 V
G2-S
= 10 mA 0.5 1.5 V
S-G1
= 10 mA 0.5 1.5 V
S-G2
=4V; VDS=5V; ID=20µA 0.3 1 V
=5V; ID=20µA 0.3 1.2 V
=4V; VDS=5V;
813mA
RG1= 120 kΩ; note 1
I
G1-SS
I
G2-SS
gate 1 cut-off current V
gate 2 cut-off current V
G2-S=VDS
G1-S=VDS
= 0; V
= 0; V
=5V − 50 nA
G1-S
=5V − 50 nA
G2-S
Note
1. R
connects gate 1 to VGG= 5 V; see Fig.20.
G1
DYNAMIC CHARACTERISTICS
Common source; T
=25°C; VDS= 5 V; V
amb
= 4 V; ID= 10 mA; unless otherwise specified.
G2-S
SYMBOL PARAMETER CONDITIONS MIN. TYP. MAX. UNIT
forward transfer admittance pulsed; Tj=25°C 222530mS
y
fs
C
ig1-s
C
ig2-s
C
os
C
rs
F noise figure f = 200 MHz; G
input capacitance at gate 1 f = 1 MHz − 2.2 2.6 pF
input capacitance at gate 2 f = 1 MHz 1 1.5 2 pF
drain-source capacitance f = 1 MHz 1 1.3 1.6 pF
reverse transfer capacitance f = 1 MHz − 25 35 fF
f = 800 MHz; G
= 2 mS; BS=B
S
S=GSopt
; BS=B
− 1 1.5 dB
Sopt
− 2 2.8 dB
Sopt
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Philips Semiconductors Product specification
N-channel dual gate MOS-FETs BF904; BF904R
100
MLD268
o
T ( C)
j
40
Y
fs
(mS)
30
20
10
0
50 0 50 150
Fig.4 Transfer admittance as a function of the
junction temperature; typical values.
gain
(dB)
10
20
30
40
50
f =50 MHz.
0
01234
handbook, halfpage
reduction
Fig.5 Typical gain reduction as a function of
the AGC voltage.
MRA769
V (V)
AGC
120
handbook, halfpage
V
unw
(dB V)
µ
110
100
90
80
0 1020304050
VDS= 5 V; VGG= 5 V; fw= 50 MHz.
f
= 60 MHz; T
unw
=25°C; RG1= 120 kΩ.
amb
gain reduction (dB)
MRA771
Fig.6 Unwanted voltage for 1% cross-modulation
as a function of gain reduction; typical
values; see Fig.20.
20
I
D
(mA)
15
10
VDS=5V.
Tj=25°C.
5
0
0
0.4 2.0
V = 4 V
G2 S
0.8 1.2 1.6
3 V 2.5 V
V (V)
Fig.7 Transfer characteristics; typical values.
MLD270
2 V
1.5 V
1 V
G1 S
1999 May 17 5