LT1001 Datasheet, PDF (7/12 Pages) Linear Technology – Precision Operational Amplifier

Offset Voltage Adjustment
The input offset voltage of the LT1001, and its drift with tempera-
ture, are permanently trimmed at wafer test to a low level.
However, if further adjustment of Vos is necessary, nulling with
a 10k or 20k potentiometer will not degrade drift with tempera-
ture. Trimming to a value other than zero creates a drift of (Vos/
300)µV/°C, e.g., if Vos is adjusted to 300 µV, the change in drift
will be 1 µV/°C. The adjustment range with a 10k or 20k pot is
approximately ±2.5mV. If less adjustment range is needed, the
sensitivity and resolution of the nulling can be improved by using
a smaller pot in conjunction with fixed resistors. The example
below has an approximate null range of ±100 µV.
Improved Sensitivity Adjustment
7.5k
1k
+15V
INPUT
7.5k
1
2– 8
7
6
LT1001
3+
4
OUTPUT
–15V
1001 F02
LT1001
0.1Hz to 10Hz Noise Test Circuit
0.1µF
100kΩ
10Ω
–
LT1001
+
DEVICE
UNDER
TEST
2kΩ
4.7 µF
VOLTAGE GAIN = 50,000
+
LT1001
–
100k
24.3k
0.1 µF
4.3k
2.2µF
22µF
SCOPE
×1
R_IN = 1MΩ
110k
1001 F03
(Peak-to-Peak noise measured in 10 sec interval)
The device under test should be warmed up for three minutes and
shielded from air currents.
DC Stabilized
1000v/µsec Op Amp
2.2µF
TANTALUM
2N5486
3.9k
1N914
0.01 µF
1k
R_IN
1k
10k
INPUT
3₊
–15V
30k
6
15pF
LT1001
2_–
30k
0.01µF
300
200Ω* _200pf
2N5160
33
1.8k
2N3866
.001
µF
470
22
390Ω
2N3904
2N3904
2N5160 2N3906
2N3866
+15V
.1µF
22µF TANTALUM
2N4440
.5Ω
.5Ω
2N4440
OUTPUT
15-60pF
TUSONIX # 519-3188
3.9k
1N914
1k
R_f
200pF
200Ω*
300
FULL POWER
BANDWIDTH 8MHz
22µF TANTALUM
1.2k
0.1µF
–15V
*ADJUST FOR
BEST SQUARE WAVE
AT OUTPUT
1001 F04
7