ETC 3SK238

3SK238
Silicon N–Channel Dual Gate MOSFET
Application
CMPAK-4
UHF RF amplifier
Features
2
• Excellent cross modulation characteristics
• Capable of low voltage operation
3
1
4
1. Source
2. Gate1
3. Gate2
4. Drain
Table 1 Absolute Maximum Ratings (Ta = 25°C)
Item
Symbol
Ratings
Unit
———————————————————————————————————————————
Drain to source voltage
VDS
12
V
———————————————————————————————————————————
Gate1 to source voltage
VG1S
±10
V
———————————————————————————————————————————
Gate2 to source voltage
VG2S
±10
V
———————————————————————————————————————————
Drain current
ID
35
mA
———————————————————————————————————————————
Channel power dissipation
Pch
100
mW
———————————————————————————————————————————
Channel temperature
Tch
125
°C
———————————————————————————————————————————
Storage temperature
Tstg
–55 to +125
°C
———————————————————————————————————————————
Marking is “XW–”.
3SK238
Table 2 Electrical Characteristics (Ta = 25°C)
Item
Symbol
Min
Typ
Max
Unit
Test conditions
———————————————————————————————————————————
Drain to source
breakdown voltage
V(BR)DSX
12
—
—
V
ID = 200 µA, VG1S = –5 V,
VG2S = –5 V
———————————————————————————————————————————
Gate1 to source
breakdown voltage
V(BR)G1SS
±10
—
—
V
IG1 = ±10 µA,
VG2S = VDS = 0
———————————————————————————————————————————
Gate2 to source
breakdown voltage
V(BR)G2SS
±10
—
—
V
IG2 = ±10 µA,
VG1S = VDS = 0
———————————————————————————————————————————
Gate1 leakage
current
IG1SS
—
—
±100
nA
VG1S = ±8 V,
VG2S = VDS = 0
———————————————————————————————————————————
Gate2 leakage
current
IG2SS
—
—
±100
nA
VG2S = ±8 V,
VG1S = VDS = 0
———————————————————————————————————————————
Drain current
IDSS
0
—
2
mA
VDS = 6 V, VG1S = 0,
VG2S = 3 V
———————————————————————————————————————————
Gate1 to source
cutoff voltage
VG1S(off)
–0.7
—
+0.7
V
VDS = 10 V, VG2S = 3V,
ID = 100 µA
———————————————————————————————————————————
Gate2 to source
cutoff voltage
VG2S(off)
–0.1
—
+0.8
V
VDS = 10 V, VG1S = 3V,
ID = 100 µA
———————————————————————————————————————————
Forward transfer
admittance
|yfs|
14
—
—
mS
VDS = 6V, VG2S = 3 V,
ID = 10 mA, f = 1 kHz
———————————————————————————————————————————
Input capacitance
Ciss
0.9
1.25
1.8
pF
——————————————————————————————
Output capacitance
Coss
0.4
0.7
1.2
pF
VDS = 6 V,
VG2S = 3 V,ID = 10 mA,
f = 1 MHz
——————————————————————————————
Reverse transfer
capacitance
Crss
—
0.015
0.03
pF
———————————————————————————————————————————
Power gain
PG
16
19.4
—
dB
——————————————————————————————
Noise figure
NF
—
2.8
4
VDS = 4 V, VG2S = 3 V,
ID = 10 mA, f = 900 MHz
dB
———————————————————————————————————————————
3SK238
Typical output characteristics
Maximum channel power dissipation curve
Pch (mW)
20
I D (mA)
200
50
1.2 V
12
1.0 V
8
0.8 V
0.6 V
4
0.4 V
VG1S = 0.2 V
0
0
50
100
150
200
Ambient Temperature Ta (°C)
2
4
6
Drain to Source Voltage
8
10
VDS (V)
20
20
12
VDS = 4 V
3V
2V
1.5 V
8
4
VDS = 4 V
2.5 V
VG2S = 1 V
0
0
0.5
1
1.5
2
–0.5
Gate1 to Source Voltage VG1S (V)
I D (mA)
(mA)
Drain current vs. gate2 to source voltage
ID
Drain current vs. Gate1 to source voltage
16
Drain Current
1.4 V
16
Drain Current
100
Drain Current
Channel Power Dissipation
150
VG2S = 3 V
16
2V
1.5 V
12
1V
8
4
0
VG1S = 0.5 V
1
2
3
4
5
Gate2 to Source Voltage V G2S (V)
3SK238
Power gain vs. drain current
20
25
20
VG2S = 3 V
15
2.5 V
10
2V
1.5 V
5
0.4
0.8
1.2
1.6
2
Gate1 to Source Voltage VG1S (V)
Noise figure vs. drain current
5
NF (dB)
16
12
8
4
1V
0
Noise Figure
PG (dB)
V DS = 6 V
f = 1 kHz
Power Gain
Forward Transfer Admittance |y fs | (mS)
Forward transfer admittance
vs. gate1 to source voltage
4
V DS = 4 V
VG2S = 3 V
f = 900 MHz
3
2
1
0
4
8
12
16
Drain Current I D (mA)
20
0
VDS = 4 V
VG2S = 3 V
f = 900 MHz
4
8
12
16
Drain Current ID (mA)
20