Datasheet
LT1994
16
1994fb
0.1F ceramic capacitor in single-supply applications.
This will help prevent thermal noise from the internal
80kΩ-80kΩ voltage divider (25nV/√Hz) and other exter-
nal sources of noise from being converted to differential
noise due to mismatches in the feedback networks. It is
also recommended that the resistive feedback networks
be comprised of 1% resistors (or better) to enhance the
output common mode rejection. This will also prevent
V
OCM
input referred common mode noise of the common
mode amplifi er path (which cannot be fi ltered) from being
converted to differential noise, degrading the differential
noise performance.
APPLICATIONS INFORMATION
SIMPLIFIED SCHEMATIC
1994 SS01
V
+
SHDN
120k
Q4
I
1
Q3
I
1
55k
V
+
V
–
OUT
+
V
+
V
–
V
+
V
–
V
OCM
V
–
V
+
V
–
V
+
V
+
V
+
V
–
BIAS
ADJUST
SHUTDOWN
CIRCUIT
CM
ADJUST
80k
80k
Q11
Q12
Q5 Q6
Q8
I
4B
OUT
+
V
+
OUT
–
Q7
I
3
BIAS
R1
4k
R2
4k
C
M2
–
+
OUT
–
V
+
V
–
V
+
V
–
BIAS
ADJUST
Q9
Q10
C
M1
IN
–
V
+
V
–
IN
+
V
+
V
–
–
+
V
+
Q1 Q2
D2
I2
Gm
2B
Gm
2A
D1
D4D3
I
4A