Datasheet

12
LT1008
1008fb
TYPICAL APPLICATIO S
U
Fast Precision Inverters
–
+
1
30pF
–15V
15V
300pF
1N4148 (4)
8
7
5
4
1
2
3
7
6
OUTPUT
6
2
3
10k
10k
4
SLEW RATE = 100V/μs
SETTLING (10V STEP) = 5μs TO 0.01%
OFFSET VOLTAGE = 30μV
BIAS CURRENT DC = 30pA
*1% METAL FILM
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
LT1008
–
+
30pF
–15V
15V
300pF
10pF
1000pF
10k*
1N4148 ×2
7
10k
INPUT
6
2
3
3
2
10k
4
8
1
1008 TA10
10k
10k*
–
+
LT318A
–15V
15k
INPUT
10k*
10k*
2pF TO 8pF
2N4393
×2
15V
OUTPUT
7
4
6
–
+
LT318A
15V
–15V
LT1008
–
+
1
8
7
8
2
OPTO-MOS*
3
*OPTO-MOS SWITCH
TYPE OFM1A
THETA-J CORP
1
4
1000pF
FILTER CUT
IN ADJUST
–15V
15V
10k
100Ω
6
OUTPUT
10k
2
3
1μF
1k
15V
LT1008
1.5M
2k
INPUT
–
+
#1
LT311A
7
8
5
3
2
1008 TA09
1
4
–15V
15V
–
+
#2
LT311A
Precision, Fast Settling, Lowpass Filter
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.