8

LT1002

LOAD RESISTANCE (

Ω)

100

300

16

12

8

4

0

1000

3k

10k

1002 G28

POSITIVE SWING

NEGATIVE SWING

TIME FROM OUTPUT SHORT (MINUTES)

0

2

50

40

30

20

10

–10

–20

–30

–40

–50

1002 G29

13

4

–55

°C

–55

°C

25

°C

25

°C

125

°C

125

°C

Output Short Circuit Current

vs Time

Output Swing vs. Load Resistance

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

potentiometer will not degrade drift with temperature.

300)

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 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-

nately, the guaranteed offset voltage match of the LT1002

is very low, in most applications offset adjustment will be

unnecessary.

Improved Sensitivity Adjustment

Standard Adjustment

–15V

+15V

3

(10)

(11)

4

(9)

(8)

13 (6)

14 (7)

OUTPUT

INPUT

1002 TA03

12 (5)

2

10k

or

20k

1

–15V

1

+15V

3

(10)

(11)

4

(9)

(8)

13 (6)

14

OUTPUT

INPUT

1002 TA04

12 (5)

2

1k

7.5k

7.5k

1

(7)