LT1008_1 Datasheet, PDF (12/16 Pages) Linear Technology – Picoamp Input Current, Microvolt Offset, Low Noise Op Amp

LT1008
TYPICAL APPLICATIO S
Precision, Fast Settling, Lowpass Filter
10k
INPUT
1.5M
2k
2_–
6
LT1008
3₊
8
1μF
1
OUTPUT
1k
15V
*OPTO-MOS SWITCH
TYPE OFM1A
THETA-J CORP
OPTO-MOS*
15V
8
1000pF
2
7
#1
LT311A
3
4
–15V
1
100Ω
FILTER CUT
IN ADJUST
15V
5
8
7
#2
LT311A
4
–15V
1
10k
3
2
1008 TA09
This circuit is useful where fast signal acquisition and high
precision are required, as in electronic scales.
The filter’s time constant is set by the 2k resistor and the
1μF capacitor until comparator 1 switches. The time
constant is then set by the 1.5M resistor and the 1μF
capacitor. Comparator 2 provides a quick reset.
The circuit settles to a final value three times as fast as a
simple 1.5M-1μF filter with almost no DC error.
Fast Precision Inverters
2pF TO 8pF
10k*
10k*
INPUT
10k*
10k _{1N4148 ×2}
10pF
10k*
INPUT
12
2N4393
×2
15k
1
15V
2_–
5
76
LT318A
3₊
4
OUTPUT
–15V
1N4148 (4)
300pF
300pF
15V
2_–
7
6
LT1008
3₊
4
8
10k
1
–15V
30pF
15V
10k
2_–
7
6
LT1008
3₊
4
8
10k
1
SLEW RATE = 100V/μs
–15V _{SETTLING (10V STEP) = 5μs TO 0.01%}
OFFSET VOLTAGE = 30μV
BIAS CURRENT DC = 30pA
30pF
*1% METAL FILM
15V
1000pF
2_–
7
6
LT318A
3₊
4
–15V
10k
OUTPUT
FULL POWER BANDWIDTH = 2MHz
SLEW RATE AT 50V/μs
SETTLING (10V STEP) = 12μs TO 0.01%
BIAS CURRENT DC = 30pA
OFFSET DRIFT = 0.3μV/°C
OFFSET VOLTAGE = 30μV
*1% METAL FILM
1008 TA10
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