J/SST/U308 Series
Siliconix
S-52424—Rev. F, 14-Apr -97 1
N-Channel JFETs
J308
J309
J310
SST308
SST309
SST310
U309
U310
Product Summary
Part Number VGS(off) (V) V(BR)GSS Min (V) gfs Min (mS) IDSS Min (mA)
J308 –1 to –6.5 –25 8 12
J309 –1 to –4 –25 10 12
J310 –2 to –6.5 –25 8 24
SST308 –1 to –6.5 –25 8 12
SST309 –1 to –4 –25 10 12
SST310 –2 to –6.5 –25 8 24
U309 –1 to –4 –25 10 12
U310 –2.5 to –6 –25 10 24
Features Benefits Applications
Excellent High Frequency Gain:
Gps 11.5 dB @ 450 MHz
Very Low Noise: 2.7 dB @ 450 MHz
Very Low Distortion
High ac/dc Switch Off-Isolation
Wideband High Gain
Very High System Sensitivity
High Quality of Amplification
High-Speed Switching Capability
High Low-Level Signal Amplification
High-Frequency Amplifier/Mixer
Oscillator
Sample-and-Hold
Very Low Capacitance Switches
Description
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D
S
G
TO-236
(SOT-23)
2
3
1
TO-226AA
(TO-92)
Top View
J308
J309
J310
D
G
S
1
2
3Top View
SST308 (Z8)*
SST309 (Z9)*
SST310 (Z0)*
*Marking Code for TO-236
Top View
U309
U310
D
S
G and Case
TO-206AC
(TO-52)
1
23
Updates to this data sheet may be obtained via facsimile by calling Siliconix FaxBack, 1-408-970-5600. Please request FaxBack document #70237.
Applications information may also be obtained via FaxBack, request document #70597.
J/SST/U308 Series
2 Siliconix
S-52424—Rev. F, 14-Apr -97
Absolute Maximum Ratings
Gate-Drain, Gate-Source Voltage –25 V. . . . . . . . . . . . . . . . . . . . . . . . . .
Gate Current : (J/SST Prefixes) 10 mA. . . . . . . . . . . . . . . .
(U Prefix) 20 mA. . . . . . . . . . . . . . . . . . . . .
Lead Temperature (1/16” from case for 10 sec.) 300_C. . . . . . . . . . . . . . .
Storage Temperature : (J/SST Prefixes) –55 to 150_C. . . . . . . . . .
(U Prefix) –65 to 175_C. . . . . . . . . . . . . . .
Operating Junction Temperature –55 to 150_C. . . . . . . . . . . . . . . . . . . .
Power Dissipation : (J/SST Prefixes)a350 mW. . . . . . . . . . . . .
(U Prefix)b500 mW. . . . . . . . . . . . . . . . . .
Notes
a. Derate 2.8 mW/_C above 25_C
b. Derate 4 mW/_C above 25_C
Specificationsa for J/SST308, J/SST309 and J/SST310
Limits
J/SST308 J/SST309 J/SST310
Parameter Symbol Test Conditions TypbMin Max Min Max Min Max Unit
Static
Gate-Source
Breakdown Voltage V(BR)GSS IG = –1 A , VDS = 0 V –35 –25 –25 –25 V
Gate-Source Cutoff Voltage VGS(off) VDS = 10 V, ID = 1 nA –1 –6.5 –1 –4 –2 –6.5
Saturation Drain CurrentcIDSS VDS = 10 V, VGS = 0 V 12 60 12 30 24 60 mA
Gate Reverse Current
IGSS
VGS = –15 V, VDS = 0 V –0.002 –1 –1 –1 nA
G
a
t
e
R
everse
C
urren
t
I
GSS TA = 125_C–0.001 –1 –1 –1 A
Gate Operating Current IGVDG = 9 V, ID = 10 mA –15 pA
Drain-Source On-Resistance rDS(on) VGS = 0 V, ID = 1 mA 35
Gate-Source Forward Voltage VGS(F) IG = 10 mA
VDS = 0 V J 0.7 1 1 1 V
Dynamic
Common-Source
Forward Transconductance gfs VDS = 10 V, ID = 10 mA
f1kH
14 8 10 8 mS
Common-Source
Output Conductance gos
DS ,D
f = 1 kHz 110 250 250 250 S
Common-Source
ICi
Ciss
V10V
J 4 5 5 5
Input Capacitance
C
iss VDS = 10 V
VGS
=
–
10 V
SST 4
pF
Common-Source
RTfCi
Crss
V
GS = –
10
V
f = 1 MHz J 1.9 2.5 2.5 2.5 p
F
Reverse Transfer Capacitance
C
rss SST 1.9
Equivalent Input
Noise Voltage enVDS = 10 V, ID = 10 mA
f = 100 Hz 6nV⁄
√Hz
High Frequency
Common-Gate
FdT d
gfg
f = 105 MHz 14
Forward Transconductance gfg f = 450 MHz 13
mS
Common-Gate
OCd
gog
f = 105 MHz 0.16 m
S
Output Conductance gog VDS = 10 V
I10A
f = 450 MHz 0.55
Common
-
Gate Power Gain
d
Gpg
DS
ID = 10 mA f = 105 MHz 16
C
ommon-
G
a
t
e
P
ower
G
a
i
n
d
G
pg f = 450 MHz 11.5
dB
Noise Figure
NF
f = 105 MHz 1.5
dB
Noise
Figure
NF
f = 450 MHz 2.7
Notes
a. TA = 25_C unless otherwise noted. NZB
b. Typical values are for DESIGN AID ONLY, not guaranteed nor subject to production testing.
c. Pulse test: PW 300 s duty cycle 3%.
d. Gain (Gpg) measured at optimum input noise match.
J/SST/U308 Series
Siliconix
S-52424—Rev. F, 14-Apr -97 3
Specificationsa for U309 and U310
Limits
U309 U310
Parameter Symbol Test Conditions TypbMin Max Min Max Unit
Static
Gate-Source Breakdown Voltage V(BR)GSS IG = –1 A , VDS = 0 V –35 –25 –25
V
Gate-Source Cutoff Voltage VGS(off) VDS = 10 V, ID = 1 nA –1 –4 –2.5 –6
V
Saturation Drain CurrentcIDSS VDS = 10 V, VGS = 0 V 12 30 24 60 mA
Gate Reverse Current
VGS = –15 V, VDS = 0 V –0.002 –0.15 –0.15 nA
G
a
t
e
R
everse
C
urren
t
GSS TA = 125_C–0.001 –0.15 –0.15 A
Gate Operating Current IGVDG = 9 V, ID = 10 mA –15 pA
Drain-Source On-Resistance rDS(on) VGS = 0 V, ID = 1 mA 35
Gate-Source Forward Voltage VGS(F) IG = 10 mA , VDS = 0 V 0.7 1 1 V
Dynamic
Common-Source
Forward Transconductance gfs VDS = 10 V, ID = 10 mA
f1kH
14 10 10 mS
Common-Source
Output Conductance gos
DS ,D
f = 1 kHz 110 250 250 S
Common-Source
Input Capacitance Ciss VDS = 10 V, VGS = –10 V
f1MH
4 5 5
pF
Common-Source
Reverse Transfer Capacitance Crss
DS ,GS
f = 1 MHz 1.9 2.5 2.5
p
F
Equivalent Input Noise Voltage enVDS = 10 V, ID = 10 mA
f = 100 Hz 6nV⁄
√Hz
High Frequency
Common-Gate
FdT d
f = 105 MHz 14
Forward Transconductance gfg f = 450 MHz 13
mS
Common-Gate
OCd
f = 105 MHz 0.16 m
S
Output Conductance gog VDS = 10 V
I10A
f = 450 MHz 0.55
Common
-
Gate Power Gain
d
S
ID = 10 mA f = 105 MHz 16 14 14
C
ommon-
G
a
t
e
P
ower
G
a
i
n
d
pg f = 450 MHz 11.5 10 10
dB
Noise Figure
f = 105 MHz 1.5 2 2
dB
Noise
Figure
f = 450 MHz 2.7 3.5 3.5
Notes
a. TA = 25_C unless otherwise noted. NZB
b. Typical values are for DESIGN AID ONLY, not guaranteed nor subject to production testing.
c. Pulse test: PW 300 s duty cycle 3%.
d. Gain (Gpg) measured at optimum input noise match.
J/SST/U308 Series
4 Siliconix
S-52424—Rev. F, 14-Apr -97
Typical Characteristics
100
0–5–4–3–1
80
20
0
50
40
10
0
Drain Current and Transconductance
vs. Gate-Source Cutoff Voltage Gate Leakage Current
Output Characteristics
On-Resistance and Output Conductance
vs. Gate-Source Cutoff Voltage Common-Source Forward Transconductance
vs. Drain Current
VGS(off) – Gate-Source Cutoff Voltage (V) VDG – Drain-Gate Voltage (V)
ID – Drain Current (mA)VGS(off) – Gate-Source Cutoff Voltage (V)
VDS – Drain-Source Voltage (V)
– Saturation Drain Current (mA)
IDSS
gfs – Forward Transconductance (mS)
– Gate Leakage
IG
gfs – Forward Transconductance (mS)
– Drain Current (mA)
ID
IDSS @ VDS = 10 V, VGS = 0 V
gfs @ VDS = 10 V, VGS = 0 V
f = 1 kHz
gfs
IDSS
TA = –55_C
25_C125_C
VGS = 0 V
–0.2 V
–0.4 V
–0.6 V
–0.8 V
VGS(off) = –3 V
60
40
–2
30
20
100
–3 –5–4–1
80
0
300
240
120
60
0
60
40
20
–20
180
rDS @ ID = 1 mA, VGS = 0 V
gos @ VDS = 10 V, VGS = 0 V, f = 1 kHz
rDS
06312159
I
GSS @ 125_C
TA = 125_C
TA = 25_C
200 A
0.1 1 10
20
16
8
4
0
12
15
0 0.40.2 0.8 1
12
6
3
0
9
0.6
–1.0 V
gos
IGSS @ 25_C
0.1 pA
1 pA
10 pA
100 pA
1 nA
10 nA
VDS = 10 V
f = 1 kHz
VGS(off) = –1.5 V
10 mA
Output Characteristics
VDS – Drain-Source Voltage (V)
– Drain Current (mA)
ID
VGS = 0 V
–1.2 V
–0.4 V
–1.6 V
–0.8 V
30
0 0.40.2 0.8 1
24
12
6
0
18
0.6
–2.0 V
–2.4 V
VGS(off) = –3 V
rDS(on) – Drain-Source On-Resistance (k )
S)g – Output Conductance (
IG @ ID = 10 mA 200 A
J/SST/U308 Series
Siliconix
S-52424—Rev. F, 14-Apr -97 5
Typical Characteristics (Cont’d)
Output Characteristics
VDS – Drain-Source Voltage (V)
– Drain Current (mA)
ID
50
042810
40
20
10
0
30
6
–2.4 V
VGS = 0 V
–0.4 V
–0.8 V
–1.2 V
–1.6 V
–2.0 V
Transfer Characteristics
VGS – Gate-Source Voltage (V)
– Drain Current (mA)
ID
30
0 –1.2–0.4 –1.6 –2
24
12
6
0
18
–0.8
TA = –55_C
VGS(off) = –1.5 V
125_C
Transfer Characteristics
VGS – Gate-Source Voltage (V)
– Drain Current (mA)
ID
100
0 –1.8–0.6 –2.4 –3
80
40
20
0
60
–1.2
TA = –55_C
25_C
VGS(off) = –3 V
125_C
30
0 –1.2 –1.6–0.4 –2
24
12
6
0–0.8
18
Transconductance vs. Gate-Source Voltage
VGS – Gate-Source Voltage (V)
VGS(off) = –1.5 V
TA = –55_C
125_C
gfs – Forward Transconductance (mS)
50
0 –1.8 –2.4–0.6 –3
40
20
10
0–1.2
30
Transconductance vs. Gate-Source Voltage
VGS – Gate-Source Voltage (V)
TA = –55_C
25_C
125_C
VGS(off) = –3 V
gfs – Forward Transconductance (mS)
VGS(off) = –3 V
VDS = 10 V VDS = 10 V
VDS = 10 V
f = 1 kHz VDS = 10 V
f = 1 kHz
25_C
25_C
Output Characteristics
VDS – Drain-Source Voltage (V)
– Drain Current (mA)
ID
VGS = 0 V
–0.2 V
–0.4 V
–0.6 V
–0.8 V
–1.0 V
20
068210
16
8
4
04
12
VGS(off) = –1.5 V
J/SST/U308 Series
6 Siliconix
S-52424—Rev. F, 14-Apr -97
Typical Characteristics (Cont’d)
1 10 100
100
80
40
20
0
60 VGS(off) = –1.5 V
VGS(off) = –3 V
On-Resistance vs. Drain Current
ID – Drain Current (mA)
1100.1
100
80
40
20
0
60
ID – Drain Current (mA)
RL+10 V
ID
Assume VDD = 15 V, VDS = 5 V
VGS(off) = –1.5 V
VGS(off) = –3 V
AV– Voltage Gain
Circuit Voltage Gain vs. Drain Current
15
0 –12 –16 –20–4
12
6
3
0
9
–8
Common-Source Input Capacitance
vs. Gate-Source Voltage
VDS = 0 V
f = 1 MHz
VDS = 5 V
VGS – Gate-Source Voltage (V)
Common-Source Reverse Feedback Capacitance
vs. Gate-Source Voltage
10
0 –12 –20–16–4
8
4
2
0
6
–8
VDS = 0 V
f = 1 MHz
VDS = 5 V
VGS – Gate-Source Voltage (V)
– Reverse Feedback Capacitance (pF)Crss
100
10
1
0.1100 1000
(mS)
TA = 25_C
VDG = 10 V
ID = 10 mA
Common–Gate
gig
big
Input Admittance vs. Frequency
f – Frequency (MHz)
100
10
1
0.1 100 1000
(mS)
TA = 25_C
VDG = 10 V
ID = 10 mA
Common–Gate
–gfg
bfg
Forward Admittance vs. Frequency
f – Frequency (MHz)
– Input Capacitance (pF)Ciss
200 500 200 500
AV+
gfs RL
1)RLgos
rDS(on) – Drain-Source On-Resistance ( )
J/SST/U308 Series
Siliconix
S-52424—Rev. F, 14-Apr -97 7
Typical Characteristics (Cont’d)
10 100 1 k 100 k10 k
20
16
8
4
0
12
Equivalent Input Noise Voltage vs. Frequency
ID = 1 mA
VDS = 10 V
ID = 10 mA
f – Frequency (Hz)
150
120
60
30
00.1 1 10
90
Output Conductance vs. Drain Current
VGS(off) = –3 V
ID – Drain Current (mA)
TA = –55_C
25_C
125_C
10
1
0.1
0.01 100 1000
(mS)
TA = 25_C
VDG = 10 V
ID = 10 mA
Common–Gate
–brg
–grg
+grg
Reverse Admittance vs. Frequency
f – Frequency (MHz)
100
10
1
0.1 100 1000
(mS)
TA = 25_C
VDG = 10 V
ID = 10 mA
Common–Gate
gog
bog
Output Admittance vs. Frequency
f – Frequency (MHz)
200 500 200 500
VDS = 10 V
f = 1 kHz
nVen/Hz
√)(– Noise Voltage
S)g – Output Conductance (