PHILIPS BF998

DISCRETE SEMICONDUCTORS
DATA SHEET
BF998; BF998R
Silicon N-channel dual-gate
MOS-FETs
Product specification
Supersedes data of April 1991
File under Discrete Semiconductors, SC07
1996 Aug 01
Philips Semiconductors
Product specification
Silicon N-channel dual-gate MOS-FETs
BF998; BF998R
FEATURES
• Short channel transistor with high forward transfer
admittance to input capacitance ratio
d
handbook, halfpage
4
3
• Low noise gain controlled amplifier up to 1 GHz.
g2
g1
APPLICATIONS
• VHF and UHF applications with 12 V supply voltage,
such as television tuners and professional
communications equipment.
1
2
s,b
Top view
DESCRIPTION
MAM039
Marking code: MOp.
Depletion type field effect transistor in a plastic
microminiature SOT143 or SOT143R package with source
and substrate interconnected. The transistors are
protected against excessive input voltage surges by
integrated back-to-back diodes between gates and
source.
Fig.1
Simplified outline (SOT143)
and symbol; BF998.
d
handbook, halfpage
3
CAUTION
4
g2
The device is supplied in an antistatic package. The
gate-source input must be protected against static
discharge during transport or handling.
g1
2
PINNING
1
s,b
PIN
SYMBOL
1
s, b
2
d
drain
3
g2
gate 2
4
g1
gate 1
Top view
DESCRIPTION
source
MAM040
Marking code: MOp.
Fig.2
Simplified outline (SOT143R)
and symbol; BF998R.
QUICK REFERENCE DATA
SYMBOL
PARAMETER
CONDITIONS
TYP.
MAX.
UNIT
VDS
drain-source voltage
−
12
V
ID
drain current
−
30
mA
Ptot
total power dissipation
−
200
mW
yfs
forward transfer admittance
24
−
mS
Cig1-s
input capacitance at gate 1
2.1
−
pF
Crs
reverse transfer capacitance
f = 1 MHz
25
−
fF
F
noise figure
f = 800 MHz
1
−
dB
Tj
operating junction temperature
−
150
°C
1996 Aug 01
2
Philips Semiconductors
Product specification
Silicon N-channel dual-gate MOS-FETs
BF998; BF998R
LIMITING VALUES
In accordance with the Absolute Maximum Rating System (IEC 134).
SYMBOL
PARAMETER
CONDITIONS
MIN.
MAX.
UNIT
VDS
drain-source voltage
−
12
V
ID
drain current
−
30
mA
±IG1
gate 1 current
−
10
mA
±IG2
gate 2 current
Ptot
total power dissipation; BF998
−
10
mA
up to Tamb = 60 °C; see Fig.3; note 1
−
200
mW
up to Tamb = 50 °C; see Fig.3; note 2
−
200
mW
Ptot
total power dissipation; BF998R up to Tamb = 50 °C; see Fig.4; note 1
−
200
mW
Tstg
storage temperature
−65
+150
°C
Tj
operating junction temperature
−
150
°C
Notes
1. Device mounted on a ceramic substrate, 8 mm × 10 mm × 0.7 mm.
2. Device mounted on a printed-circuit board.
MLA198
MGA002
handbook, halfpage
handbook, halfpage
200
200
(2)
Ptot max
(1)
Ptot max
(mW)
(mW)
100
100
0
0
0
100
200
Tamb
0
(o C)
100
200
Tamb (°C)
(1) Ceramic substrate.
(2) Printed-circuit board.
Fig.3 Power derating curves; BF998.
1996 Aug 01
Fig.4 Power derating curve; BF998R.
3
Philips Semiconductors
Product specification
Silicon N-channel dual-gate MOS-FETs
BF998; BF998R
THERMAL CHARACTERISTICS
SYMBOL
Rth j-a
Rth j-a
PARAMETER
CONDITIONS
thermal resistance from junction to ambient in free air; BF998
VALUE
UNIT
note 1
460
K/W
note 2
500
K/W
thermal resistance from junction to ambient in free air; BF998R note 1
500
K/W
Notes
1. Device mounted on a ceramic substrate, 8 mm × 10 mm × 0.7 mm.
2. Device mounted on a printed-circuit board.
STATIC CHARACTERISTICS
Tj = 25 °C; unless otherwise specified.
SYMBOL
PARAMETER
CONDITIONS
MIN.
MAX.
UNIT
±V(BR)G1-SS gate 1-source breakdown voltage
VG2-S = VDS = 0; IG1-SS = ±10 mA
6
20
V
±V(BR)G2-SS gate 2-source breakdown voltage
VG1-S = VDS = 0; IG2-SS = ±10 mA
6
20
V
−V(P)G1-S
gate 1-source cut-off voltage
VG2-S = 4 V; VDS = 8 V; ID = 20 µA
−
2.0
V
−V(P)G2-S
gate 2-source cut-off voltage
VG1-S = 0; VDS = 8 V; ID = 20 µA
−
1.5
V
IDSS
drain-source current
VG2-S = 4 V; VDS = 8 V; VG1-S = 0; note 1
2
18
mA
±IG1-SS
gate 1 cut-off current
VG2-S = VDS = 0; VG1-S = ±5 V
−
50
nA
±IG2-SS
gate 2 cut-off current
VG1-S = VDS = 0; VG2-S = ±5 V
−
50
nA
MAX.
UNIT
−
mS
Note
1. Measured under pulse condition.
DYNAMIC CHARACTERISTICS
Common source; Tamb = 25 °C; VDS = 8 V; VG2-S = 4 V; ID = 10 mA.
SYMBOL
PARAMETER
CONDITIONS
MIN.
TYP.
yfs
forward transfer admittance
f = 1 kHz
21
24
Cig1-s
input capacitance at gate 1
f = 1 MHz
−
2.1
2.5
pF
Cig2-s
input capacitance at gate 2
f = 1 MHz
−
1.2
−
pF
Cos
output capacitance
f = 1 MHz
−
1.05
−
pF
Crs
reverse transfer capacitance
f = 1 MHz
−
25
−
fF
F
noise figure
f = 200 MHz; GS = 2 mS; BS = BSopt
−
0.6
−
dB
f = 800 MHz; GS = 3.3 mS; BS = BSopt
−
1.0
−
dB
1996 Aug 01
4
Philips Semiconductors
Product specification
Silicon N-channel dual-gate MOS-FETs
BF998; BF998R
MGE813
24
MGE815
24
handbook,
halfpage
I
handbook,
halfpage
I
D
(mA)
D
(mA)
20
VG1-S =
0.4 V
20
3V
VG2-S = 4 V
2V
1V
0.3 V
16
0.2 V
12
0.1 V
16
12
0V
8
−0.1 V
8
−0.2 V
4
0
0
2
4
6
8
0V
4
−0.3 V
−0.4 V
−0.5 V
0
−1
10
0
VG2-S = 4 V; Tamb = 25 °C.
1
VG1 (V)
VDS (V)
VDS = 8 V; Tamb = 25 °C.
Fig.5 Output characteristics; typical values.
Fig.6 Transfer characteristics; typical values.
MGE814
24
MGE811
30
handbook,
I halfpage
handbook, halfpage
D
(mA)
20
max
4V
3V
2V
|yfs|
(mS)
24
typ
1V
16
18
12
min
12
8
6
4
0
−1600
VG2-S = 0 V
−1200
−800
−400
0
VG1 (mV)
0
400
0
1996 Aug 01
4
8
12
16
20
ID (mA)
VDS = 8 V; VG2-S = 4 V; Tamb = 25 °C.
Fig.7
0.5 V
VDS = 8 V; Tamb = 25 °C.
Drain current as a function of gate 1
voltage; typical values.
Fig.8
5
Forward transfer admittance as a function of
drain current; typical values.
Philips Semiconductors
Product specification
Silicon N-channel dual-gate MOS-FETs
BF998; BF998R
MGE812
MGE810
30
1.5
handbook, halfpage
handbook, halfpage
VG2-S = 4 V
|yfs|
Cos
(pF)
(mS)
24
1.4
3V
18
1.3
2V
12
1.2
12 mA
1V
6
1.1
10 mA
8 mA
0V
0
−1
1.0
0
VG1 (V)
1
4
VDS = 8 V; Tamb = 25 °C.
Fig.9
6
8
10
12
VDS (V)
14
VG2-S = 4 V; f = 1 MHz; Tamb = 25 °C.
Forward transfer admittance as a function of
gate 1 voltage; typical values.
Fig.10 Output capacitance as a function of
drain-source voltage; typical values.
MBH479
MGE809
2.3
Cis
2.4
handbook, halfpage
handbook, halfpage
(pF)
Cis
(pF)
2.1
2.3
1.9
2.2
1.7
2.1
1.5
1.3
−2.4
−1.6
−0.8
2.0
0
0.8
VG1-S (V)
6
VDS = 8 V; VG2-S = 4 V; f = 1 MHz; Tamb = 25 °C.
2
0
−2
VG2−S (V)
VDS = 8 V; VG1-S = 0 V; f = 1 MHz; Tamb = 25 °C.
Fig.11 Gate 1 input capacitance as a function of
gate 1-source voltage; typical values.
1996 Aug 01
4
Fig.12 Gate 1 input capacitance as a function of
gate 2-source voltage; typical values.
6
Philips Semiconductors
Product specification
Silicon N-channel dual-gate MOS-FETs
MGC466
BF998; BF998R
MGC467
10 3
10
y is
(mS)
10 3
ϕ
y rs
(µS)
b is
rs
(deg)
ϕ rs
10 2
1
10 2
y rs
10 1
10
10
g is
10 2
10
102
10
VDS = 8 V; VG2-S = 4 V; ID = 10 mA; Tamb = 25 °C.
MGC468
y fs
f (MHz)
10 3
Fig.14 Reverse transfer admittance and phase as a
function of frequency; typical values.
MGC469
10 2
10
yos
(mS)
ϕ fs
y fs
(mS)
102
VDS = 8 V; VG2-S = 4 V; ID = 10 mA; Tamb = 25 °C.
Fig.13 Input admittance as a function of the
frequency; typical values.
10 2
1
1
10 3
f (MHz)
bos
(deg)
1
ϕ
10
10
fs
gos
10 1
1
1
10
102
f (MHz)
10 2
10
10 3
VDS = 8 V; VG2-S = 4 V; ID = 10 mA; Tamb = 25 °C.
f (MHz)
10 3
VDS = 8 V; VG2-S = 4 V; ID = 10 mA; Tamb = 25 °C.
Fig.15 Forward transfer admittance and phase as a
function of frequency; typical values.
1996 Aug 01
102
Fig.16 Output admittance as a function of the
frequency; typical values.
7
Philips Semiconductors
Product specification
Silicon N-channel dual-gate MOS-FETs
BF998; BF998R
VDD
handbook, full pagewidth
47 µF
1 nF
Vagc
1 nF
1 nF
20 µH
1 nF
50 Ω
output
1.8 kΩ
47 kΩ
L2
1 nF
50 Ω
input
C1
5.5 pF
1 nF
360 Ω
15 pF
10 pF
L1
140 kΩ
VDD
1 nF
D1
BB405
330 kΩ
100 kΩ
330 kΩ
1 nF
1 nF
Vtun
Vtun
input
output
VDD = 12 V; GS = 2 mS; GL = 0.5 mS.
L1 = 45 nH; 4 turns 0.8 mm copper wire, internal diameter 4 mm.
L2 = 160 nH; 3 turns 0.8 mm copper wire, internal diameter 8 mm.
Tapped at approximately half a turn from the cold side, to adjust GL = 0.5 mS. C1 adjusted for GS = 2 mS.
Fig.17 Gain control test circuit at f = 200 MHz.
1996 Aug 01
D2
BB405
8
MGE802
Philips Semiconductors
Product specification
Silicon N-channel dual-gate MOS-FETs
Vagc
VDD
handbook, full pagewidth
BF998; BF998R
VDD
1 nF
1 nF
140 kΩ
100 kΩ
1 nF
L4
270 kΩ
50 Ω
input
1 nF
L3
1 nF
L1
L2
1 nF
C1
2 to 18 pF
C3
0.5 to
3.5 pF
C2
0.5 to 3.5 pF
50 Ω
output
C4
4 to 40 pF
MGE801
1.8 kΩ
360 Ω
VDD
VDD = 12 V; GS = 3.3 mS; GL = 1 mS.
L1 = L4 = 200 nH; 11 turns 0.5 mm copper wire, without spacing, internal diameter 3 mm.
L2 = 2 cm, silvered 0.8 mm copper wire, 4 mm above ground plane.
L3 = 2 cm, silvered 0.5 mm copper wire, 4 mm above ground plane.
Fig.18 Gain control test circuit at f = 800 MHz.
1996 Aug 01
1 nF
9
Philips Semiconductors
Product specification
Silicon N-channel dual-gate MOS-FETs
BF998; BF998R
MGE807
MGE808
0
0
handbook, halfpage
handbook, halfpage
∆Gtr
∆Gtr
(dB)
(dB)
−10
−10
−20
−20
−30
−30
IDSS =
−40
−50
max
typ
min
−40
max
typ
min
0
IDSS =
−50
2
4
6
8
10
0
2
4
Vagc (V)
VDD = 12 V; f = 200 MHz; Tamb = 25 °C.
8
Vagc (V)
10
VDD = 12 V; f = 800 MHz; Tamb = 25 °C.
Fig.19 Automatic gain control characteristics
measured in circuit of Fig.17.
1996 Aug 01
6
Fig.20 Automatic gain control characteristics
measured in circuit of Fig.18.
10
Philips Semiconductors
Product specification
Silicon N-channel dual-gate MOS-FETs
BF998; BF998R
PACKAGE OUTLINES
handbook, full pagewidth
3.0
2.8
0.150
0.090
0.75
0.60
B
1.9
4
3
0.1
max
o
10
max
0.2 M A B
A
2.5
max
1.4
1.2
o
10
max
1
1.1
max
o
30
max
0.88
2
0
0.1
0.48
0.1 M A B
0
0.1
MBC845
1.7
TOP VIEW
Dimensions in mm.
Fig.21 SOT143.
3.0
2.8
handbook, full pagewidth
0.150
0.090
0.40
0.25
B
1.9
3
4
0.1
max
o
10
max
0.2 M A
A
1.4
1.2
o
2.5
max
10
max
1
2
1.1
max
o
30
max
0.48
0.38
0.88
0.78
1.7
0.1 M B
TOP VIEW
Dimensions in mm.
Fig.22 SOT143R.
1996 Aug 01
11
MBC844
Philips Semiconductors
Product specification
Silicon N-channel dual-gate MOS-FETs
BF998; BF998R
DEFINITIONS
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.
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.
1996 Aug 01
12