LT1078_15 Datasheet, PDF (13/20 Pages) Linear Technology – Micropower, Dual and Quad, Single Supply, Precision Op Amps

TYPICAL APPLICATIONS
Micropower, 10ppm/°C, ±5V Reference
2M
9V
LT1034BC-1.2
220k
120k _{3 +} 8
1
1/2 LT1078
2_–
4
–9V _510k
1%
5.000V_{OUT 1M}
1M _{6 –}
1/2 LT1078
510k _{5 +}
7
– 5.000V_OUT
LT1078/79 • TA03
160k ^20k
1% _{SUPPLY CURRENT = 9V BATTERY = 115μA}
–9V BATTERY = 85μA
OUTPUT NOISE = 36μV_P-P, 0.1Hz TO 10Hz
THE LT1078 CONTRIBUTES LESS THAN 3% OF THE TOTAL OUTPUT NOISE AND
DRIFT WITH TIME AND TEMPERATURE. THE ACCURACY OF THE –5V OUTPUT
DEPENDS ON THE MATCHING OF THE TWO 1M RESISTORS
LT1078/LT1079
Gain of 10 Difference Amplifier
10M
1M
–IN
1M
+IN
3V
–
1/2 LT1078
+
OUTPUT
0.0035V TO 2.4V
LT1078/79 • TA04
10M
BANDWIDTH= 20kHz
OUTPUT OFFSET= 0.7mV
OUTPUT NOISE= 80μV_P-P (0.1Hz TO 10Hz)
260μV_RMS OVER FULL
BANDWIDTH
THE USEFULNESS OF DIFFERENCE AMPLIFIERS IS LIMITED BY
THE FACT THAT THE INPUT RESISTANCE IS EQUAL TO THE SOURCE
RESISTANCE. THE PICOAMPERE OFFSET CURRENT AND LOW
CURRENT NOISE OF THE LT1078 ALLOWS THE USE OF 1M SOURCE
RESISTORS WITHOUT DEGRADATION IN PERFORMANCE. IN ADDITION,
WITH MEGOHM RESISTORS MICROPOWER OPERATION CAN BE MAINTAINED
Picoampere Input Current, Triple Op Amp Instrumentation Amplifier with Bias Current Cancellation
–IN
3₊
R2
1
1M
1/4 LT1079
2_–
R1
1M
R3
2R
R_G
9.1M
20M
200k
9_–
6_–
R1
1M
7
1/4 LT1079
8
1/4 LT1079
10 ₊
OUTPUT
4mV TO 8.2V
LT`1078/79 • TA05
+IN
5₊
R2
1M _R3
9.1M
R
9V
10M
12 ₊
4
2R
14
1/4 LT1079
20M _{13 –}
11
( ) GAIN = 1 + 2R1 R3 = 100 FOR VALUES SHOWN
R_G R2
INPUT BIAS CURRENT TYPICALLY < 150pA
INPUT RESISTANCE = 3R = 30M FOR VALUES SHOWN
NEGATIVE COMMON MODE LIMIT = (I_B)(2R) + 20mV ≈ 140mV
GAIN BANDWIDTH PRODUCT = 1.8MHz
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