01/99
B-41
IFN421, IFN422, IFN423
Dual N-Channel Silicon Junction Field-Effect Transistor
樓 Very High Input Impedance
Differential Amplifiers
樓 Electrometers
Absolute maximum ratings at T
A
= 25隆C
Device Dissipation (Derate 3.2 mW/擄C to 50擄C)
Total Device Dissipation (Derate 6 mW/擄C to 150擄C)
Storage Temperature Range
400 mW
750 mW
鈥?65擄C to 200擄C
At 25擄C free air temperature:
Static Electrical Characteristics
Gate Source Breakdown Voltage
Gate to Gate Breakdown Voltage
Gate Reverse Current
Gate Operating Current
Gate Source Cutoff Voltage
Gate Source Voltage
Drain Saturation Current (Pulsed)
Dynamic Electrical Characteristics
Common Source Forward Transconductance
g
fs
IFN421, IFN422, IFN423
Min
V
(BR)GSS
BV
G1G2
I
GSS
I
G
V
GS(OFF)
V
GS
I
DSS
60
鈥?0.4
鈥?40
鹵40
鈥?
鈥?
鈥?0.25
鈥?250
鈥?
鈥?1.8
1000
Typ
鈥?60
Max
Unit
V
V
pA
nA
pA
pA
V
V
碌A(chǔ)
Process NJ01
Test Conditions
I
G
= 鈥?1 碌A(chǔ), V
DS
= 脴V
I
G
= 鈥?1 碌A(chǔ), I
D
= 脴A, I
S
= 脴A
V
GS
= 鈥?20V, V
DS
= 脴V
V
GS
= 鈥?20V, V
DS
= 脴V
V
DS
= 10V, I
D
= 30 碌A(chǔ)
V
DS
= 10V, I
D
= 30 碌A(chǔ)
V
DS
= 10V, I
D
= 1 nA
V
DS
= 10V, I
D
= 30 碌A(chǔ)
V
DS
= 10V, V
GS
= 脴 V
T
A
= +125擄C
T
A
= +125擄C
100
1500
3
3
1.5
20
70
1
碌S
碌S
pF
pF
nV/鈭欻z
V
DS
= 10V, V
GS
= 脴 V
V
DS
= 10V, I
D
= 30 碌A(chǔ)
V
DS
= 10V, V
GS
= 脴 V
V
DS
= 10V, V
GS
= 脴 V
V
DS
= 10V, I
D
= 30 碌A(chǔ)
V
DS
= 10V, I
D
= 30 碌A(chǔ)
R
G
= 10 M鈩?/div>
f = 1 kHz
f = 1 kHz
f = 1 MHz
f = 1 MHz
f = 10 Hz
f = 10 Hz
Common Source Output Conductance
Common Source Input Capacitance
Equivalent Circuit Input Noise Voltage
g
os
C
iss
e
N
爐
NF
Common Source Reverse Transfer Capacitance
C
rss
Noise Figure
dB
Max - IFN421 IFN422 IFN423
Differential Gate Source Voltage
Differential Gate Source Voltage
With Temperature
|V
GS1
鈥?V
GS2
|
|V
GS1
鈥?V
GS2
|
10
10
15
25
25
40
mV
碌V/擄C
V
DG
= 10V, I
D
= 30 碌A(chǔ)
V
DG
= 10V, I
D
= 30 碌A(chǔ)
T
A
= 鈥?55擄C
T
B
= 25擄C
T
C
= 125擄C
鈭員
Min - IFN421 IFN422 IFN423
Common Mode Rejection Ratio
CMRR
90
80
80
dB
V
DG
= 10V to 20V, I
D
= 30 碌A(chǔ)
TO脨78 Package
See Section G for Outline Dimensions
Pin Configuration
1 Source 1, 2 Drain 1, 3 Gate 1, 4 Case,
5 Source 2, 6 Drain 2, 7 Gate 2,
8 Omitted
1000 N. Shiloh Road, Garland, TX 75042
(972) 487-1287
FAX
(972) 276-3375
www.interfet.com
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