AD581

Rev. C | Page 10 of 12

10 V reference guarantees a maximum full-scale temperature

coefficient of 8 ppm/°C over the commercial range. The 10 V

reference also supplies the normal 1 mA bipolar offset current

through the 9.95 kΩ bipolar offset resistor. Consequently, the

bipolar offset TC depends only on TC matching of the bipolar

offset resistor to the input reference resistor and is guaranteed

to 3 ppm/°C.

1

18

2

3

4

5

AD7574

(TOP VIEW)

AD581

DIGITAL

SUPPLY

RETURN

GROUND

INTERTIE

ANALOG

GROUND

ANALOG

SUPPLY

RETURN

R3

1.2k

Ω

5%

GND

0.1µF

+5V

–15V

–10V REF

R1 1k

R2 2k

Ω

SIGNAL

INPUT

0V TO +10V

IS NOT REQUIRED.

Figure 15. AD581 as −10 V Reference for CMOS ADC

PNP LOGIC SWITCHES AND LEVEL SHIFTERS

0.1µF

0.1µF

OP1177

OP AMP

OUTPUT

5k

Ω

(8k

Ω)

A

5k

Ω

(8k

Ω)

R4

20k

Ω, 15T

R3

3.0M

Ω

9.950k

Ω

(15.95k)

CONTROL

AMP

CONTROL AMP

SUMMING

JUNCTION

100

Ω, 15T

R2

GAIN ADJ.

10V

R1

100

Ω, 15T

BIPOLAR OFFSET ADJ.

GND

19.95k

Ω

0.5mA

–15V

AD565A

+15V

–15V

UNIPOLAR

OFFSET ADJ.

A = ANALOG GROUND

24

23

22

21

20

19

18

17

16

15

14

13

2

3

11

10

9

12

8

7

2

1

6

4

5

3

A

–15V +5V/+15V

+15V

AD581

Figure 16. Precision 12-Bit DAC