OP467

REV. C

–14–

FAST I-TO-V CONVERTER

The fast slew rate and fast settling time of the OP467 are well

suited to the fast buffers and I-to-V converters used in variety of

applications. The circuit in Figure 46 is a unipolar quad D/A

converter consisting of only two ICs. The current output of the

DAC8408 is converted to a voltage by the OP467 configured as

an I-to-V converter. This circuit is capable of settling to 0.1%

within 200 ns. Figures 47 and 48 show the full-scale settling

time of the outputs. To obtain reliable circuit performance, keep

OP467 short to minimize parasitic capacitance.

10

0%

100

90

260.0ns

2V

50mV

100ns

Figure 47. Voltage Output Settling Time

15

DGND

DAC8408

+5V

+10V

+10V

0.1 F

+15V

–15V

C2

10pF

C1

10pF

0.1 F

7

OP467

5

4

11

6

OP467

2

3

1

1

2

3

7

8

9

10

11

12

4

5

6

13

14

+

+10V

+10V

DIGITAL

CONTROL

SIGNALS

C3

10pF

C4

10pF

14

12

13

OP467

DB0 (LSB)

DB1

DB2

DB3

DB4

DB5

8

10

9

OP467

(MSB) DB7

DB6

28

27

26

22

21

20

19

18

17

25

24

23

16

+

+

–

+

–

R/

W

A/

B

DS1

DS2

Figure 46. Quad DAC Unipolar Operation

10

0%

100

90

251.0ns

2V

50mV

100ns

Figure 48. Voltage Output Settling Time

3pF

OP467

I-V

DAC-8408

1k

50

604

60.4

2k

DC OFFSET

2k

AD847