01/99 B-3
2N3821, 2N3822
N-Channel Silicon Junction Field-Effect Transistor
Absolute maximum ratings at T
A
= 25¡C
Reverse Gate Source & Reverse Gate Drain Voltage – 50 V
Continuous Forward Gate Current 10 mA
Continuous Device Power Dissipation 300 mW
Power Derating 2mW/°C
TOÐ72 Package
Dimensions in Inches (mm)
Pin Configuration
1 Source, 2 Drain, 3 Gate, 4 Case
At 25°C free air temperature: 2N3821 2N3822 Process NJ32
Static Electrical Characteristics Min Max Min Max Unit Test Conditions
Gate Source Breakdown Voltage V
(BR)GSS
– 50 – 50 V I
G
= – 1 µA, V
DS
= ØV
Gate Reverse Current I
GSS
– 0.1 – 0.1 nA V
GS
= – 30V, V
DS
= ØV
– 0.1 – 0.1 µA V
GS
= – 30V, V
DS
= ØV T
A
= 150°C
– 0.5 – 2 V V
DS
= 15V, I
D
= 50 µA
Gate Source Voltage V
GS
– 1 – 4 V V
DS
= 15V, I
D
= 200 µA
VV
DS
= 15V, I
D
= 400 µA
Gate Source Cutoff Voltage V
GS(OFF)
– 4 – 6 V V
DS
= 15V, I
D
= 0.5 nA
Drain Saturation Current (Pulsed) I
DSS
0.5 2.5 2 10 mA V
DS
= 15V, V
GS
= ØV
Drain Cutoff Current I
D(OFF)
nA V
DS
= 15V, V
GS
= – 8V
µA V
DS
= 15V, V
GS
= – 8V T
A
= 150°C
Dynamic Electrical Characteristics
Drain Source ON Resistance r
ds(on)
Ω V
GS
= ØV, I
D
= Ø V f = 1 kHz
Common Source
g
fs
1500 4500 3000 6500 µS V
DS
= 15V, V
GS
= ØV f = 1 kHz
Forward Transconductance
Common Source
| Y
fs
| 1500 3000 µS V
DS
= 15V, V
GS
= ØV f = 100 MHz
Forward Transmittance
Common Source Output Conductance g
os
10 20 µS V
DS
= 15V, V
GS
= ØV f = 1 kHz
Common Source Input Capacitance C
iss
66pF
DS
= 15V, V
GS
= ØV f = 1 MHz
Common Source
C
rss
22pFV
DS
= 15V, V
GS
= ØV f = 1 MHz
Reverse Transfer Capacitance
Equivalent Short Circuit
¯e
N
200 200 nV/√Hz V
DS
= 15V, V
GS
= ØV f = 10 Hz
Input Noise Voltage
Noise Figure NF 5 5 dB
V
DS
= 15V, V
GS
= ØV
f = 10 Hz
R
G
= 1 MΩ
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Databook.fxp 1/13/99 2:09 PM Page B-3