LT1002_15 Datasheet, PDF (8/16 Pages) Linear Technology – Dual, Matched Precision Operational Amplifier

LT1002
TYPICAL PERFORMANCE CHARACTERISTICS
Output Swing vs. Load Resistance
16
NEGATIVE SWING
12
POSITIVE SWING
8
4
0
100
V_S = ±15V
T_A = 25°C
300
1000
3k
LOAD RESISTANCE (Ω)
10k
1002 G28
Output Short Circuit Current
vs Time
50
40
–55°C
30
25°C
20
125°C
10
V_S = ±15V
–10
125°C
–20
25°C
–30
–55°C
–40
–50
0
1
2
3
4
TIME FROM OUTPUT SHORT (MINUTES)
1002 G29
APPLICATIONS INFORMATION
The LT1002 dual amplifier may be inserted directly into
OP-10, OP207, OP227 sockets with or without removal of
external nulling potentiometers.
Offset Voltage Adjustment The input offset voltage of the
LT1002, and its drift with temperature, are permanently
trimmed at wafer testing to a low level. However, if further
adjustment of V_OS is necessary, nulling with a 10k or 20k
potentiometer will not degrade drift with temperature.
Trimming to a value other than zero creates a drift of (V_OS/
300)µV/°C, e.g. if V_OS is adjusted to 300µV, the change in
drift will be 1µV/°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 conjunc-
tion with fixed resistors. The example has an approximate
null range of ±100µV.
In matching applications, both amplifiers can be trimmed
to zero, or the offset of one amplifier can be trimmed to
match the offset of the other. Offset adjustment, however,
slightly degrades the gain, common-mode and power-
supply rejection match between the two op amps. Fortu-
8
nately, the guaranteed offset voltage match of the LT1002
is very low, in most applications offset adjustment will be
unnecessary.
Standard Adjustment
10k
or
15V
20k
1 ₍₈₎
3 – 2 ₍₉₎
(10)
1/2
INPUT _{4 +LT1002}
14 (7)
OUTPUT
13 (6)
(11)
12 (5)
–15V
1002 TA03
Improved Sensitivity Adjustment
7.5k
1k
15V
7.5k
1 ₍₈₎
3 – ² (9)
(10)
1/2 ^{14 (7)}
INPUT _{4 +LT1002}
13 (6)
(11)
12 (5)
OUTPUT
–15V
1002 TA04
1002fb