Datasheet

14
LT2078/LT2079
20789fa
TYPICAL APPLICATIONS
U
Single Supply, Micropower, Second Order Lowpass Filter with 60Hz Notch
–
+
+
–
6
5
7
1/2 LT2078
2.64M
0.1%
2.64M
0.1%
1/2 LT2078
3
2
1
OUTPUT
TYPICAL OFFSET
≈ 600µV
LT2078/79 • TA10
5V
8
4
1.35M
0.1%
IN
2000pF
0.5%
1000pF
0.5%
1000pF
0.5%
0.02µF
5.1M
1%
120k
5%
100pF
0.01µF
27.6k
0.1%
27.6k
0.1%
f
C
= 40Hz
Q = 30
Micropower Multiplier/Divider
–
+
6
5
13
12
1/4 LT2079
4
11
714
–
+
2
3
1/4 LT2079
1
–
+
9
10
1/4 LT2079
8
–1.5V TO –9V
9V
505k
0.1%
505k
0.1%
505k
0.1%
220pF 220pF
30k
5%
30k
5%
Q1
–
+
220pF
30k
5%
Y INPUT
(5mV TO 50V)
X INPUT
(5mV TO 50V)
Q2 Q4
499k
0.5%
10k
GAIN
Z INPUT
(5mV TO 50V)
OUTPUT
(5mV TO 8V)
1/4 LT2079
Q1,Q2, Q3, Q4 = MAT-04
TYPICAL LINEARITY = 0.01% OF FULL-SCALE OUTPUT
Q3
OUTPUT = , POSITIVE INPUTS ONLY
(X)(Y)
(Z)
NEGATIVE SUPPLY CURRENT = 165µA +
X + Y+ Z + OUT
500k
POSITIVE SUPPLY CURRENT = 165µA +
BANDWIDTH (< 3V
P-P
SIGNAL): X AND Y INPUTS = 10kHz
Z INPUT = 4kHz
OUT
500k
lt2078/79 • TA11
Micropower Dead Zone Generator
–
+
2
3
1
1/4 LT2079
510k
1M**
1M**
1M*
Q1
2N4393
–
+
6
5
7
1/4 LT2079
–
+
9
10
8
1/4 LT2079
–
+
13
12
14
1/4 LT2079
1M**
Q4
Q2 Q3
470k
1M*
GAIN
200k
510k
1M**
510k
4
11
9V
1M
1M 680k
1M
1N914
1N914
Q5
–9V
Q6
2N4393
1000pF
V
SET
DEAD ZONE
CONTROL INPUT
0.4V TO 5V
V
OUT
LT2078/79 • TA12
BIPOLAR SYMMETRY IS EXCELLENT
BECAUSE ONE DEVICE, Q2,
SETS BOTH LIMITS
SUPPLY CURRENT ≈ 240µA
BANDWIDTH = 150kHz
INPUT
*
**
1% FILM
RATIO MATCH 0.05%
Q2, Q3, Q4, Q5 CA3096 TRANSISTOR ARRAY
V
SET
V
SET
V
OUT
V
IN