INA166

7

SBOS178

FIGURE 3. Offset Voltage Adjustment Circuit.

OFFSET VOLTAGE TRIM

A variable voltage applied to pin 10, as shown in Figure 3, can

be used to adjust the output offset voltage. A voltage applied

to pin 10 is summed with the output signal. An op amp

connected as a buffer is used to provide a low impedance at

pin 10 to assure good common-mode rejection.

FIGURE 4. Buffer for Increase Output Current.

INA166

V+

V–

V

O

V+

150

Ω

10k

Ω

150

Ω

100

µA

100

µA

8

4

3

12

5

10

11

6

9

V–

OPA237

OUTPUT SENSE

An output sense terminal allows greater gain accuracy in

driving the load. By connecting the sense connection at the

load, I • R voltage loss to the load is included inside the

feedback loop. Current drive can be increased by connecting

a buffer amp inside the feedback loop, as shown in Figure 4.

+15V

–15V

V

O

±250mA

Output Drive

BW

BUF634 connected

for wide bandwidth.

8

11

6

10

9

INA166

BUF634

Sense

4

3

12

5